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Posted to commits@arrow.apache.org by ju...@apache.org on 2016/08/26 15:20:21 UTC

[1/2] arrow git commit: ARROW-264: File format

Repository: arrow
Updated Branches:
  refs/heads/master ec51d5667 -> 803afeb50


http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowWriter.java
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diff --git a/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowWriter.java b/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowWriter.java
new file mode 100644
index 0000000..9881a22
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowWriter.java
@@ -0,0 +1,179 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.WritableByteChannel;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.arrow.vector.schema.ArrowBuffer;
+import org.apache.arrow.vector.schema.ArrowRecordBatch;
+import org.apache.arrow.vector.schema.FBSerializable;
+import org.apache.arrow.vector.types.pojo.Schema;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+import io.netty.buffer.ArrowBuf;
+
+public class ArrowWriter implements AutoCloseable {
+  private static final Logger LOGGER = LoggerFactory.getLogger(ArrowWriter.class);
+
+  private static final byte[] MAGIC = "ARROW1".getBytes();
+
+  private final WritableByteChannel out;
+
+  private final Schema schema;
+
+  private final List<ArrowBlock> recordBatches = new ArrayList<>();
+
+  private long currentPosition = 0;
+
+  private boolean started = false;
+
+  public ArrowWriter(WritableByteChannel out, Schema schema) {
+    this.out = out;
+    this.schema = schema;
+  }
+
+  private void start() throws IOException {
+    writeMagic();
+  }
+
+  private long write(byte[] buffer) throws IOException {
+    return write(ByteBuffer.wrap(buffer));
+  }
+
+  private long writeZeros(int zeroCount) throws IOException {
+    return write(new byte[zeroCount]);
+  }
+
+  private long align() throws IOException {
+    if (currentPosition % 8 != 0) { // align on 8 byte boundaries
+      return writeZeros(8 - (int)(currentPosition % 8));
+    }
+    return 0;
+  }
+
+  private long write(ByteBuffer buffer) throws IOException {
+    long length = buffer.remaining();
+    out.write(buffer);
+    currentPosition += length;
+    return length;
+  }
+
+  private static byte[] intToBytes(int value) {
+    byte[] outBuffer = new byte[4];
+    outBuffer[3] = (byte)(value >>> 24);
+    outBuffer[2] = (byte)(value >>> 16);
+    outBuffer[1] = (byte)(value >>>  8);
+    outBuffer[0] = (byte)(value >>>  0);
+    return outBuffer;
+  }
+
+  private long writeIntLittleEndian(int v) throws IOException {
+    return write(intToBytes(v));
+  }
+
+  // TODO: write dictionaries
+
+  public void writeRecordBatch(ArrowRecordBatch recordBatch) throws IOException {
+    checkStarted();
+    align();
+    // write metadata header
+    long offset = currentPosition;
+    write(recordBatch);
+    align();
+    // write body
+    long bodyOffset = currentPosition;
+    List<ArrowBuf> buffers = recordBatch.getBuffers();
+    List<ArrowBuffer> buffersLayout = recordBatch.getBuffersLayout();
+    if (buffers.size() != buffersLayout.size()) {
+      throw new IllegalStateException("the layout does not match: " + buffers.size() + " != " + buffersLayout.size());
+    }
+    for (int i = 0; i < buffers.size(); i++) {
+      ArrowBuf buffer = buffers.get(i);
+      ArrowBuffer layout = buffersLayout.get(i);
+      long startPosition = bodyOffset + layout.getOffset();
+      if (startPosition != currentPosition) {
+        writeZeros((int)(startPosition - currentPosition));
+      }
+      write(buffer);
+      if (currentPosition != startPosition + layout.getSize()) {
+        throw new IllegalStateException("wrong buffer size: " + currentPosition + " != " + startPosition + layout.getSize());
+      }
+    }
+    int metadataLength = (int)(bodyOffset - offset);
+    if (metadataLength <= 0) {
+      throw new InvalidArrowFileException("invalid recordBatch");
+    }
+    long bodyLength = currentPosition - bodyOffset;
+    LOGGER.debug(String.format("RecordBatch at %d, metadata: %d, body: %d", offset, metadataLength, bodyLength));
+    // add metadata to footer
+    recordBatches.add(new ArrowBlock(offset, metadataLength, bodyLength));
+  }
+
+  private void write(ArrowBuf buffer) throws IOException {
+    write(buffer.nioBuffer(buffer.readerIndex(), buffer.readableBytes()));
+  }
+
+  private void checkStarted() throws IOException {
+    if (!started) {
+      started = true;
+      start();
+    }
+  }
+
+  public void close() throws IOException {
+    try {
+      long footerStart = currentPosition;
+      writeFooter();
+      int footerLength = (int)(currentPosition - footerStart);
+      if (footerLength <= 0 ) {
+        throw new InvalidArrowFileException("invalid footer");
+      }
+      writeIntLittleEndian(footerLength);
+      LOGGER.debug(String.format("Footer starts at %d, length: %d", footerStart, footerLength));
+      writeMagic();
+    } finally {
+      out.close();
+    }
+  }
+
+  private void writeMagic() throws IOException {
+    write(MAGIC);
+    LOGGER.debug(String.format("magic written, now at %d", currentPosition));
+  }
+
+  private void writeFooter() throws IOException {
+    // TODO: dictionaries
+    write(new ArrowFooter(schema, Collections.<ArrowBlock>emptyList(), recordBatches));
+  }
+
+  private long write(FBSerializable writer) throws IOException {
+    FlatBufferBuilder builder = new FlatBufferBuilder();
+    int root = writer.writeTo(builder);
+    builder.finish(root);
+    return write(builder.dataBuffer());
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/file/InvalidArrowFileException.java
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diff --git a/java/vector/src/main/java/org/apache/arrow/vector/file/InvalidArrowFileException.java b/java/vector/src/main/java/org/apache/arrow/vector/file/InvalidArrowFileException.java
new file mode 100644
index 0000000..3ec75dc
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/file/InvalidArrowFileException.java
@@ -0,0 +1,27 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+public class InvalidArrowFileException extends RuntimeException {
+  private static final long serialVersionUID = 1L;
+
+  public InvalidArrowFileException(String message) {
+    super(message);
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowBuffer.java
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diff --git a/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowBuffer.java b/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowBuffer.java
new file mode 100644
index 0000000..3aa3e52
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowBuffer.java
@@ -0,0 +1,81 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.schema;
+
+import org.apache.arrow.flatbuf.Buffer;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+public class ArrowBuffer implements FBSerializable {
+
+  private int page;
+  private long offset;
+  private long size;
+
+  public ArrowBuffer(int page, long offset, long size) {
+    super();
+    this.page = page;
+    this.offset = offset;
+    this.size = size;
+  }
+
+  public int getPage() {
+    return page;
+  }
+
+  public long getOffset() {
+    return offset;
+  }
+
+  public long getSize() {
+    return size;
+  }
+
+  @Override
+  public int hashCode() {
+    final int prime = 31;
+    int result = 1;
+    result = prime * result + (int) (offset ^ (offset >>> 32));
+    result = prime * result + page;
+    result = prime * result + (int) (size ^ (size >>> 32));
+    return result;
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (this == obj)
+      return true;
+    if (obj == null)
+      return false;
+    if (getClass() != obj.getClass())
+      return false;
+    ArrowBuffer other = (ArrowBuffer) obj;
+    if (offset != other.offset)
+      return false;
+    if (page != other.page)
+      return false;
+    if (size != other.size)
+      return false;
+    return true;
+  }
+
+  @Override
+  public int writeTo(FlatBufferBuilder builder) {
+    return Buffer.createBuffer(builder, page, offset, size);
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowFieldNode.java
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diff --git a/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowFieldNode.java b/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowFieldNode.java
new file mode 100644
index 0000000..71dd0ab
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowFieldNode.java
@@ -0,0 +1,53 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.schema;
+
+import org.apache.arrow.flatbuf.FieldNode;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+public class ArrowFieldNode implements FBSerializable {
+
+  private final int length;
+  private final int nullCount;
+
+  public ArrowFieldNode(int length, int nullCount) {
+    super();
+    this.length = length;
+    this.nullCount = nullCount;
+  }
+
+  @Override
+  public int writeTo(FlatBufferBuilder builder) {
+    return FieldNode.createFieldNode(builder, length, nullCount);
+  }
+
+  public int getNullCount() {
+    return nullCount;
+  }
+
+  public int getLength() {
+    return length;
+  }
+
+  @Override
+  public String toString() {
+    return "ArrowFieldNode [length=" + length + ", nullCount=" + nullCount + "]";
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowRecordBatch.java
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diff --git a/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowRecordBatch.java b/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowRecordBatch.java
new file mode 100644
index 0000000..9162efd
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowRecordBatch.java
@@ -0,0 +1,127 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.schema;
+
+import static org.apache.arrow.vector.schema.FBSerializables.writeAllStructsToVector;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.arrow.flatbuf.RecordBatch;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+import io.netty.buffer.ArrowBuf;
+
+public class ArrowRecordBatch implements FBSerializable, AutoCloseable {
+  private static final Logger LOGGER = LoggerFactory.getLogger(ArrowRecordBatch.class);
+
+  /** number of records */
+  private final int length;
+
+  /** Nodes correspond to the pre-ordered flattened logical schema */
+  private final List<ArrowFieldNode> nodes;
+
+  private final List<ArrowBuf> buffers;
+
+  private final List<ArrowBuffer> buffersLayout;
+
+  private boolean closed = false;
+
+  /**
+   * @param length how many rows in this batch
+   * @param nodes field level info
+   * @param buffers will be retained until this recordBatch is closed
+   */
+  public ArrowRecordBatch(int length, List<ArrowFieldNode> nodes, List<ArrowBuf> buffers) {
+    super();
+    this.length = length;
+    this.nodes = nodes;
+    this.buffers = buffers;
+    List<ArrowBuffer> arrowBuffers = new ArrayList<>();
+    long offset = 0;
+    for (ArrowBuf arrowBuf : buffers) {
+      arrowBuf.retain();
+      long size = arrowBuf.readableBytes();
+      arrowBuffers.add(new ArrowBuffer(0, offset, size));
+      LOGGER.debug(String.format("Buffer in RecordBatch at %d, length: %d", offset, size));
+      offset += size;
+      if (offset % 8 != 0) { // align on 8 byte boundaries
+        offset += 8 - (offset % 8);
+      }
+    }
+    this.buffersLayout = Collections.unmodifiableList(arrowBuffers);
+  }
+
+  public int getLength() {
+    return length;
+  }
+
+  /**
+   * @return the FieldNodes corresponding to the schema
+   */
+  public List<ArrowFieldNode> getNodes() {
+    return nodes;
+  }
+
+  /**
+   * @return the buffers containing the data
+   */
+  public List<ArrowBuf> getBuffers() {
+    if (closed) {
+      throw new IllegalStateException("already closed");
+    }
+    return buffers;
+  }
+
+  /**
+   * @return the serialized layout if we send the buffers on the wire
+   */
+  public List<ArrowBuffer> getBuffersLayout() {
+    return buffersLayout;
+  }
+
+  @Override
+  public int writeTo(FlatBufferBuilder builder) {
+    RecordBatch.startNodesVector(builder, nodes.size());
+    int nodesOffset = writeAllStructsToVector(builder, nodes);
+    RecordBatch.startBuffersVector(builder, buffers.size());
+    int buffersOffset = writeAllStructsToVector(builder, buffersLayout);
+    RecordBatch.startRecordBatch(builder);
+    RecordBatch.addLength(builder, length);
+    RecordBatch.addNodes(builder, nodesOffset);
+    RecordBatch.addBuffers(builder, buffersOffset);
+    return RecordBatch.endRecordBatch(builder);
+  }
+
+  /**
+   * releases the buffers
+   */
+  public void close() {
+    if (!closed) {
+      closed = true;
+      for (ArrowBuf arrowBuf : buffers) {
+        arrowBuf.release();
+      }
+    }
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowVectorType.java
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diff --git a/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowVectorType.java b/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowVectorType.java
new file mode 100644
index 0000000..e3d3e34
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/schema/ArrowVectorType.java
@@ -0,0 +1,47 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.schema;
+
+import org.apache.arrow.flatbuf.VectorType;
+
+public class ArrowVectorType {
+
+  public static final ArrowVectorType VALUES = new ArrowVectorType(VectorType.VALUES);
+  public static final ArrowVectorType OFFSET = new ArrowVectorType(VectorType.OFFSET);
+  public static final ArrowVectorType VALIDITY = new ArrowVectorType(VectorType.VALIDITY);
+  public static final ArrowVectorType TYPE = new ArrowVectorType(VectorType.TYPE);
+
+  private final short type;
+
+  public ArrowVectorType(short type) {
+    this.type = type;
+  }
+
+  public short getType() {
+    return type;
+  }
+
+  @Override
+  public String toString() {
+    try {
+      return VectorType.name(type);
+    } catch (ArrayIndexOutOfBoundsException e) {
+      return "Unlnown type " + type;
+    }
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/schema/FBSerializable.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/schema/FBSerializable.java b/java/vector/src/main/java/org/apache/arrow/vector/schema/FBSerializable.java
new file mode 100644
index 0000000..d23ed91
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/schema/FBSerializable.java
@@ -0,0 +1,24 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.schema;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+public interface FBSerializable {
+  int writeTo(FlatBufferBuilder builder);
+}
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/schema/FBSerializables.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/schema/FBSerializables.java b/java/vector/src/main/java/org/apache/arrow/vector/schema/FBSerializables.java
new file mode 100644
index 0000000..31c17ad
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/schema/FBSerializables.java
@@ -0,0 +1,37 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.schema;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+public class FBSerializables {
+
+  public static int writeAllStructsToVector(FlatBufferBuilder builder, List<? extends FBSerializable> all) {
+    // struct vectors have to be created in reverse order
+    List<? extends FBSerializable> reversed = new ArrayList<>(all);
+    Collections.reverse(reversed);
+    for (FBSerializable element : reversed) {
+      element.writeTo(builder);
+    }
+    return builder.endVector();
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/schema/TypeLayout.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/schema/TypeLayout.java b/java/vector/src/main/java/org/apache/arrow/vector/schema/TypeLayout.java
new file mode 100644
index 0000000..1275e0e
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/schema/TypeLayout.java
@@ -0,0 +1,208 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.schema;
+
+import static java.util.Arrays.asList;
+import static org.apache.arrow.flatbuf.Precision.DOUBLE;
+import static org.apache.arrow.flatbuf.Precision.SINGLE;
+import static org.apache.arrow.vector.schema.VectorLayout.booleanVector;
+import static org.apache.arrow.vector.schema.VectorLayout.byteVector;
+import static org.apache.arrow.vector.schema.VectorLayout.dataVector;
+import static org.apache.arrow.vector.schema.VectorLayout.offsetVector;
+import static org.apache.arrow.vector.schema.VectorLayout.typeVector;
+import static org.apache.arrow.vector.schema.VectorLayout.validityVector;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.arrow.flatbuf.UnionMode;
+import org.apache.arrow.vector.types.pojo.ArrowType;
+import org.apache.arrow.vector.types.pojo.ArrowType.ArrowTypeVisitor;
+import org.apache.arrow.vector.types.pojo.ArrowType.Binary;
+import org.apache.arrow.vector.types.pojo.ArrowType.Bool;
+import org.apache.arrow.vector.types.pojo.ArrowType.Date;
+import org.apache.arrow.vector.types.pojo.ArrowType.Decimal;
+import org.apache.arrow.vector.types.pojo.ArrowType.FloatingPoint;
+import org.apache.arrow.vector.types.pojo.ArrowType.Int;
+import org.apache.arrow.vector.types.pojo.ArrowType.IntervalDay;
+import org.apache.arrow.vector.types.pojo.ArrowType.IntervalYear;
+import org.apache.arrow.vector.types.pojo.ArrowType.Null;
+import org.apache.arrow.vector.types.pojo.ArrowType.Time;
+import org.apache.arrow.vector.types.pojo.ArrowType.Timestamp;
+import org.apache.arrow.vector.types.pojo.ArrowType.Tuple;
+import org.apache.arrow.vector.types.pojo.ArrowType.Union;
+import org.apache.arrow.vector.types.pojo.ArrowType.Utf8;
+
+/**
+ * The layout of vectors for a given type
+ * It defines its own vectors followed by the vectors for the children
+ * if it is a nested type (Tuple, List, Union)
+ */
+public class TypeLayout {
+
+  public static TypeLayout getTypeLayout(final ArrowType arrowType) {
+    TypeLayout layout = arrowType.accept(new ArrowTypeVisitor<TypeLayout>() {
+
+      @Override public TypeLayout visit(Int type) {
+        return newFixedWidthTypeLayout(dataVector(type.getBitWidth()));
+      }
+
+      @Override public TypeLayout visit(Union type) {
+        List<VectorLayout> vectors;
+        switch (type.getMode()) {
+          case UnionMode.Dense:
+            vectors = asList(
+                // TODO: validate this
+                validityVector(),
+                typeVector(),
+                offsetVector() // offset to find the vector
+                );
+            break;
+          case UnionMode.Sparse:
+            vectors = asList(
+                validityVector(),
+                typeVector()
+                );
+            break;
+          default:
+            throw new UnsupportedOperationException("Unsupported Union Mode: " + type.getMode());
+        }
+        return new TypeLayout(vectors);
+      }
+
+      @Override public TypeLayout visit(Tuple type) {
+        List<VectorLayout> vectors = asList(
+            // TODO: add validity vector in Map
+//            validityVector()
+            );
+        return new TypeLayout(vectors);
+      }
+
+      @Override public TypeLayout visit(Timestamp type) {
+        return newFixedWidthTypeLayout(dataVector(64));
+      }
+
+      @Override public TypeLayout visit(org.apache.arrow.vector.types.pojo.ArrowType.List type) {
+        List<VectorLayout> vectors = asList(
+            validityVector(),
+            offsetVector()
+            );
+        return new TypeLayout(vectors);
+      }
+
+      @Override public TypeLayout visit(FloatingPoint type) {
+        int bitWidth;
+        switch (type.getPrecision()) {
+        case SINGLE:
+          bitWidth = 32;
+          break;
+        case DOUBLE:
+          bitWidth = 64;
+          break;
+        default:
+          throw new UnsupportedOperationException("Unsupported Precision: " + type.getPrecision());
+        }
+        return newFixedWidthTypeLayout(dataVector(bitWidth));
+      }
+
+      @Override public TypeLayout visit(Decimal type) {
+        // TODO: check size
+        return newFixedWidthTypeLayout(dataVector(64)); // actually depends on the type fields
+      }
+
+      @Override public TypeLayout visit(Bool type) {
+        return newFixedWidthTypeLayout(booleanVector());
+      }
+
+      @Override public TypeLayout visit(Binary type) {
+        return newVariableWidthTypeLayout();
+      }
+
+      @Override public TypeLayout visit(Utf8 type) {
+        return newVariableWidthTypeLayout();
+      }
+
+      private TypeLayout newVariableWidthTypeLayout() {
+        return newPrimitiveTypeLayout(validityVector(), offsetVector(), byteVector());
+      }
+
+      private TypeLayout newPrimitiveTypeLayout(VectorLayout... vectors) {
+        return new TypeLayout(asList(vectors));
+      }
+
+      public TypeLayout newFixedWidthTypeLayout(VectorLayout dataVector) {
+        return newPrimitiveTypeLayout(validityVector(), dataVector);
+      }
+
+      @Override
+      public TypeLayout visit(Null type) {
+        return new TypeLayout(Collections.<VectorLayout>emptyList());
+      }
+
+      @Override
+      public TypeLayout visit(Date type) {
+        return newFixedWidthTypeLayout(dataVector(64));
+      }
+
+      @Override
+      public TypeLayout visit(Time type) {
+        return newFixedWidthTypeLayout(dataVector(64));
+      }
+
+      @Override
+      public TypeLayout visit(IntervalDay type) { // TODO: check size
+        return newFixedWidthTypeLayout(dataVector(64));
+      }
+
+      @Override
+      public TypeLayout visit(IntervalYear type) { // TODO: check size
+        return newFixedWidthTypeLayout(dataVector(64));
+      }
+    });
+    return layout;
+  }
+
+  private final List<VectorLayout> vectors;
+
+  public TypeLayout(List<VectorLayout> vectors) {
+    super();
+    this.vectors = vectors;
+  }
+
+  public TypeLayout(VectorLayout... vectors) {
+    this(asList(vectors));
+  }
+
+
+  public List<VectorLayout> getVectors() {
+    return vectors;
+  }
+
+  public List<ArrowVectorType> getVectorTypes() {
+    List<ArrowVectorType> types = new ArrayList<>(vectors.size());
+    for (VectorLayout vector : vectors) {
+      types.add(vector.getType());
+    }
+    return types;
+  }
+
+  public String toString() {
+    return "TypeLayout{" + vectors + "}";
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/schema/VectorLayout.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/schema/VectorLayout.java b/java/vector/src/main/java/org/apache/arrow/vector/schema/VectorLayout.java
new file mode 100644
index 0000000..421ebcb
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/schema/VectorLayout.java
@@ -0,0 +1,93 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.schema;
+
+import static org.apache.arrow.vector.schema.ArrowVectorType.OFFSET;
+import static org.apache.arrow.vector.schema.ArrowVectorType.TYPE;
+import static org.apache.arrow.vector.schema.ArrowVectorType.VALIDITY;
+import static org.apache.arrow.vector.schema.ArrowVectorType.VALUES;
+
+public class VectorLayout {
+
+  private static final VectorLayout VALIDITY_VECTOR = new VectorLayout(VALIDITY, 1);
+  private static final VectorLayout OFFSET_VECTOR = new VectorLayout(OFFSET, 32);
+  private static final VectorLayout TYPE_VECTOR = new VectorLayout(TYPE, 32);
+  private static final VectorLayout BOOLEAN_VECTOR = new VectorLayout(VALUES, 1);
+  private static final VectorLayout VALUES_64 = new VectorLayout(VALUES, 64);
+  private static final VectorLayout VALUES_32 = new VectorLayout(VALUES, 32);
+  private static final VectorLayout VALUES_16 = new VectorLayout(VALUES, 16);
+  private static final VectorLayout VALUES_8 = new VectorLayout(VALUES, 8);
+
+  public static VectorLayout typeVector() {
+    return TYPE_VECTOR;
+  }
+
+  public static VectorLayout offsetVector() {
+    return OFFSET_VECTOR;
+  }
+
+  public static VectorLayout dataVector(int typeBitWidth) {
+    switch (typeBitWidth) {
+    case 8:
+      return VALUES_8;
+    case 16:
+      return VALUES_16;
+    case 32:
+      return VALUES_32;
+    case 64:
+      return VALUES_64;
+    default:
+      throw new IllegalArgumentException("only 8, 16, 32, or 64 bits supported");
+    }
+  }
+
+  public static VectorLayout booleanVector() {
+    return BOOLEAN_VECTOR;
+  }
+
+  public static VectorLayout validityVector() {
+    return VALIDITY_VECTOR;
+  }
+
+  public static VectorLayout byteVector() {
+    return dataVector(8);
+  }
+
+  private final int typeBitWidth;
+
+  private final ArrowVectorType type;
+
+  private VectorLayout(ArrowVectorType type, int typeBitWidth) {
+    super();
+    this.type = type;
+    this.typeBitWidth = typeBitWidth;
+  }
+
+  public int getTypeBitWidth() {
+    return typeBitWidth;
+  }
+
+  public ArrowVectorType getType() {
+    return type;
+  }
+
+  @Override
+  public String toString() {
+    return String.format("{width=%s,type=%s}", typeBitWidth, type);
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/types/Types.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/types/Types.java b/java/vector/src/main/java/org/apache/arrow/vector/types/Types.java
index c34882a..4d0d9ee 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/types/Types.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/types/Types.java
@@ -17,8 +17,14 @@
  */
 package org.apache.arrow.vector.types;
 
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.arrow.flatbuf.Precision;
 import org.apache.arrow.flatbuf.Type;
+import org.apache.arrow.flatbuf.UnionMode;
 import org.apache.arrow.memory.BufferAllocator;
+import org.apache.arrow.vector.FieldVector;
 import org.apache.arrow.vector.NullableBigIntVector;
 import org.apache.arrow.vector.NullableBitVector;
 import org.apache.arrow.vector.NullableDateVector;
@@ -38,7 +44,6 @@ import org.apache.arrow.vector.NullableUInt4Vector;
 import org.apache.arrow.vector.NullableUInt8Vector;
 import org.apache.arrow.vector.NullableVarBinaryVector;
 import org.apache.arrow.vector.NullableVarCharVector;
-import org.apache.arrow.vector.SmallIntVector;
 import org.apache.arrow.vector.ValueVector;
 import org.apache.arrow.vector.ZeroVector;
 import org.apache.arrow.vector.complex.ListVector;
@@ -85,9 +90,6 @@ import org.apache.arrow.vector.types.pojo.ArrowType.Utf8;
 import org.apache.arrow.vector.types.pojo.Field;
 import org.apache.arrow.vector.util.CallBack;
 
-import java.util.HashMap;
-import java.util.Map;
-
 public class Types {
 
   public static final Field NULL_FIELD = new Field("", true, Null.INSTANCE, null);
@@ -104,8 +106,8 @@ public class Types {
   public static final Field TIMESTAMP_FIELD = new Field("", true, new Timestamp(""), null);
   public static final Field INTERVALDAY_FIELD = new Field("", true, IntervalDay.INSTANCE, null);
   public static final Field INTERVALYEAR_FIELD = new Field("", true, IntervalYear.INSTANCE, null);
-  public static final Field FLOAT4_FIELD = new Field("", true, new FloatingPoint(0), null);
-  public static final Field FLOAT8_FIELD = new Field("", true, new FloatingPoint(1), null);
+  public static final Field FLOAT4_FIELD = new Field("", true, new FloatingPoint(Precision.SINGLE), null);
+  public static final Field FLOAT8_FIELD = new Field("", true, new FloatingPoint(Precision.DOUBLE), null);
   public static final Field LIST_FIELD = new Field("", true, List.INSTANCE, null);
   public static final Field VARCHAR_FIELD = new Field("", true, Utf8.INSTANCE, null);
   public static final Field VARBINARY_FIELD = new Field("", true, Binary.INSTANCE, null);
@@ -120,7 +122,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return ZeroVector.INSTANCE;
       }
 
@@ -136,7 +138,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
          return new MapVector(name, allocator, callBack);
       }
 
@@ -153,7 +155,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableTinyIntVector(name, allocator);
       }
 
@@ -169,8 +171,8 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
-        return new SmallIntVector(name, allocator);
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+        return new NullableSmallIntVector(name, allocator);
       }
 
       @Override
@@ -185,7 +187,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableIntVector(name, allocator);
       }
 
@@ -201,7 +203,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableBigIntVector(name, allocator);
       }
 
@@ -217,7 +219,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableDateVector(name, allocator);
       }
 
@@ -233,7 +235,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableTimeVector(name, allocator);
       }
 
@@ -249,7 +251,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableTimeStampVector(name, allocator);
       }
 
@@ -265,7 +267,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableIntervalDayVector(name, allocator);
       }
 
@@ -281,7 +283,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableIntervalDayVector(name, allocator);
       }
 
@@ -290,14 +292,14 @@ public class Types {
         return new IntervalYearWriterImpl((NullableIntervalYearVector) vector);
       }
     },
-    FLOAT4(new FloatingPoint(0)) {
+    FLOAT4(new FloatingPoint(Precision.SINGLE)) {
       @Override
       public Field getField() {
         return FLOAT4_FIELD;
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableFloat4Vector(name, allocator);
       }
 
@@ -306,14 +308,14 @@ public class Types {
         return new Float4WriterImpl((NullableFloat4Vector) vector);
       }
     },   //  4 byte ieee 754
-    FLOAT8(new FloatingPoint(1)) {
+    FLOAT8(new FloatingPoint(Precision.DOUBLE)) {
       @Override
       public Field getField() {
         return FLOAT8_FIELD;
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableFloat8Vector(name, allocator);
       }
 
@@ -329,7 +331,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableBitVector(name, allocator);
       }
 
@@ -345,7 +347,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableVarCharVector(name, allocator);
       }
 
@@ -361,7 +363,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableVarBinaryVector(name, allocator);
       }
 
@@ -381,7 +383,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableDecimalVector(name, allocator, precisionScale[0], precisionScale[1]);
       }
 
@@ -397,7 +399,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableUInt1Vector(name, allocator);
       }
 
@@ -413,7 +415,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableUInt2Vector(name, allocator);
       }
 
@@ -429,7 +431,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableUInt4Vector(name, allocator);
       }
 
@@ -445,7 +447,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new NullableUInt8Vector(name, allocator);
       }
 
@@ -461,7 +463,7 @@ public class Types {
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new ListVector(name, allocator, callBack);
       }
 
@@ -470,14 +472,14 @@ public class Types {
         return new UnionListWriter((ListVector) vector);
       }
     },
-    UNION(Union.INSTANCE) {
+    UNION(new Union(UnionMode.Sparse)) {
       @Override
       public Field getField() {
         throw new UnsupportedOperationException("Cannot get simple field for Union type");
       }
 
       @Override
-      public ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
+      public FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale) {
         return new UnionVector(name, allocator, callBack);
       }
 
@@ -499,7 +501,7 @@ public class Types {
 
     public abstract Field getField();
 
-    public abstract ValueVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale);
+    public abstract FieldVector getNewVector(String name, BufferAllocator allocator, CallBack callBack, int... precisionScale);
 
     public abstract FieldWriter getNewFieldWriter(ValueVector vector);
   }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Field.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Field.java b/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Field.java
index 49d0503..36712b9 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Field.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Field.java
@@ -18,19 +18,24 @@
 package org.apache.arrow.vector.types.pojo;
 
 
-import com.google.common.collect.ImmutableList;
-import com.google.flatbuffers.FlatBufferBuilder;
+import static org.apache.arrow.vector.types.pojo.ArrowType.getTypeForField;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
 
-import static org.apache.arrow.vector.types.pojo.ArrowType.getTypeForField;
+import org.apache.arrow.vector.schema.ArrowVectorType;
+import org.apache.arrow.vector.schema.TypeLayout;
+
+import com.google.common.collect.ImmutableList;
+import com.google.flatbuffers.FlatBufferBuilder;
 
 public class Field {
   private final String name;
   private final boolean nullable;
   private final ArrowType type;
   private final List<Field> children;
+  private final TypeLayout typeLayout;
 
   public Field(String name, boolean nullable, ArrowType type, List<Field> children) {
     this.name = name;
@@ -41,18 +46,32 @@ public class Field {
     } else {
       this.children = children;
     }
+    this.typeLayout = TypeLayout.getTypeLayout(type);
   }
 
   public static Field convertField(org.apache.arrow.flatbuf.Field field) {
     String name = field.name();
     boolean nullable = field.nullable();
     ArrowType type = getTypeForField(field);
+    List<ArrowVectorType> buffers = new ArrayList<>();
+    for (int i = 0; i < field.buffersLength(); ++i) {
+      buffers.add(new ArrowVectorType(field.buffers(i)));
+    }
     ImmutableList.Builder<Field> childrenBuilder = ImmutableList.builder();
     for (int i = 0; i < field.childrenLength(); i++) {
       childrenBuilder.add(convertField(field.children(i)));
     }
     List<Field> children = childrenBuilder.build();
-    return new Field(name, nullable, type, children);
+    Field result = new Field(name, nullable, type, children);
+    TypeLayout typeLayout = result.getTypeLayout();
+    if (typeLayout.getVectors().size() != field.buffersLength()) {
+      List<ArrowVectorType> types = new ArrayList<>();
+      for (int i = 0; i < field.buffersLength(); i++) {
+        types.add(new ArrowVectorType(field.buffers(i)));
+      }
+      throw new IllegalArgumentException("Deserialized field does not match expected vectors. expected: " + typeLayout.getVectorTypes() + " got " + types);
+    }
+    return result;
   }
 
   public int getField(FlatBufferBuilder builder) {
@@ -63,12 +82,18 @@ public class Field {
       childrenData[i] = children.get(i).getField(builder);
     }
     int childrenOffset = org.apache.arrow.flatbuf.Field.createChildrenVector(builder, childrenData);
+    short[] buffersData = new short[typeLayout.getVectors().size()];
+    for (int i = 0; i < buffersData.length; i++) {
+      buffersData[i] = typeLayout.getVectors().get(i).getType().getType();
+    }
+    int buffersOffset =  org.apache.arrow.flatbuf.Field.createBuffersVector(builder, buffersData );
     org.apache.arrow.flatbuf.Field.startField(builder);
     org.apache.arrow.flatbuf.Field.addName(builder, nameOffset);
     org.apache.arrow.flatbuf.Field.addNullable(builder, nullable);
     org.apache.arrow.flatbuf.Field.addTypeType(builder, type.getTypeType());
     org.apache.arrow.flatbuf.Field.addType(builder, typeOffset);
     org.apache.arrow.flatbuf.Field.addChildren(builder, childrenOffset);
+    org.apache.arrow.flatbuf.Field.addBuffers(builder, buffersOffset);
     return org.apache.arrow.flatbuf.Field.endField(builder);
   }
 
@@ -88,6 +113,10 @@ public class Field {
     return children;
   }
 
+  public TypeLayout getTypeLayout() {
+    return typeLayout;
+  }
+
   @Override
   public boolean equals(Object obj) {
     if (!(obj instanceof Field)) {
@@ -102,4 +131,9 @@ public class Field {
                     (this.children.size() == 0 && that.children == null));
 
   }
+
+  @Override
+  public String toString() {
+    return String.format("Field{name=%s, type=%s, children=%s, layout=%s}", name, type, children, typeLayout);
+  }
 }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Schema.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Schema.java b/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Schema.java
index 9e28941..231be9b 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Schema.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/types/pojo/Schema.java
@@ -18,15 +18,13 @@
 package org.apache.arrow.vector.types.pojo;
 
 
-import com.google.common.collect.ImmutableList;
-import com.google.flatbuffers.FlatBufferBuilder;
+import static org.apache.arrow.vector.types.pojo.Field.convertField;
 
-import java.nio.ByteBuffer;
 import java.util.List;
 import java.util.Objects;
 
-import static org.apache.arrow.vector.types.pojo.ArrowType.getTypeForField;
-import static org.apache.arrow.vector.types.pojo.Field.convertField;
+import com.google.common.collect.ImmutableList;
+import com.google.flatbuffers.FlatBufferBuilder;
 
 public class Schema {
   private List<Field> fields;
@@ -71,4 +69,9 @@ public class Schema {
     List<Field> fields = childrenBuilder.build();
     return new Schema(fields);
   }
+
+  @Override
+  public String toString() {
+    return "Schema" + fields;
+  }
 }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/test/java/org/apache/arrow/vector/TestVectorUnloadLoad.java
----------------------------------------------------------------------
diff --git a/java/vector/src/test/java/org/apache/arrow/vector/TestVectorUnloadLoad.java b/java/vector/src/test/java/org/apache/arrow/vector/TestVectorUnloadLoad.java
new file mode 100644
index 0000000..85bb2cf
--- /dev/null
+++ b/java/vector/src/test/java/org/apache/arrow/vector/TestVectorUnloadLoad.java
@@ -0,0 +1,89 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector;
+
+import java.io.IOException;
+
+import org.apache.arrow.memory.BufferAllocator;
+import org.apache.arrow.memory.RootAllocator;
+import org.apache.arrow.vector.complex.MapVector;
+import org.apache.arrow.vector.complex.impl.ComplexWriterImpl;
+import org.apache.arrow.vector.complex.impl.SingleMapReaderImpl;
+import org.apache.arrow.vector.complex.reader.BaseReader.MapReader;
+import org.apache.arrow.vector.complex.writer.BaseWriter.ComplexWriter;
+import org.apache.arrow.vector.complex.writer.BaseWriter.MapWriter;
+import org.apache.arrow.vector.complex.writer.BigIntWriter;
+import org.apache.arrow.vector.complex.writer.IntWriter;
+import org.apache.arrow.vector.schema.ArrowRecordBatch;
+import org.apache.arrow.vector.types.Types.MinorType;
+import org.apache.arrow.vector.types.pojo.Schema;
+import org.junit.AfterClass;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestVectorUnloadLoad {
+
+  static final BufferAllocator allocator = new RootAllocator(Integer.MAX_VALUE);
+
+  @Test
+  public void test() throws IOException {
+    int count = 10000;
+    Schema schema;
+
+    try (
+        BufferAllocator originalVectorsAllocator = allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", originalVectorsAllocator, null)) {
+      ComplexWriter writer = new ComplexWriterImpl("root", parent);
+      MapWriter rootWriter = writer.rootAsMap();
+      IntWriter intWriter = rootWriter.integer("int");
+      BigIntWriter bigIntWriter = rootWriter.bigInt("bigInt");
+      for (int i = 0; i < count; i++) {
+        intWriter.setPosition(i);
+        intWriter.writeInt(i);
+        bigIntWriter.setPosition(i);
+        bigIntWriter.writeBigInt(i);
+      }
+      writer.setValueCount(count);
+
+      VectorUnloader vectorUnloader = new VectorUnloader((MapVector)parent.getChild("root"));
+      schema = vectorUnloader.getSchema();
+
+      try (
+          ArrowRecordBatch recordBatch = vectorUnloader.getRecordBatch();
+          BufferAllocator finalVectorsAllocator = allocator.newChildAllocator("final vectors", 0, Integer.MAX_VALUE);
+          MapVector newParent = new MapVector("parent", finalVectorsAllocator, null)) {
+        MapVector root = newParent.addOrGet("root", MinorType.MAP, MapVector.class);
+        VectorLoader vectorLoader = new VectorLoader(schema, root);
+
+        vectorLoader.load(recordBatch);
+
+        MapReader rootReader = new SingleMapReaderImpl(newParent).reader("root");
+        for (int i = 0; i < count; i++) {
+          rootReader.setPosition(i);
+          Assert.assertEquals(i, rootReader.reader("int").readInteger().intValue());
+          Assert.assertEquals(i, rootReader.reader("bigInt").readLong().longValue());
+        }
+      }
+    }
+  }
+
+  @AfterClass
+  public static void afterClass() {
+    allocator.close();
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/test/java/org/apache/arrow/vector/file/ByteArrayReadableSeekableByteChannel.java
----------------------------------------------------------------------
diff --git a/java/vector/src/test/java/org/apache/arrow/vector/file/ByteArrayReadableSeekableByteChannel.java b/java/vector/src/test/java/org/apache/arrow/vector/file/ByteArrayReadableSeekableByteChannel.java
new file mode 100644
index 0000000..7c423d5
--- /dev/null
+++ b/java/vector/src/test/java/org/apache/arrow/vector/file/ByteArrayReadableSeekableByteChannel.java
@@ -0,0 +1,80 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.SeekableByteChannel;
+
+public class ByteArrayReadableSeekableByteChannel implements SeekableByteChannel {
+  private byte[] byteArray;
+  private int position = 0;
+
+  public ByteArrayReadableSeekableByteChannel(byte[] byteArray) {
+    if (byteArray == null) {
+      throw new NullPointerException();
+    }
+    this.byteArray = byteArray;
+  }
+
+  @Override
+  public boolean isOpen() {
+    return byteArray != null;
+  }
+
+  @Override
+  public void close() throws IOException {
+    byteArray = null;
+  }
+
+  @Override
+  public int read(final ByteBuffer dst) throws IOException {
+    int remainingInBuf = byteArray.length - this.position;
+    int length = Math.min(dst.remaining(), remainingInBuf);
+    dst.put(this.byteArray, this.position, length);
+    this.position += length;
+    return length;
+  }
+
+  @Override
+  public long position() throws IOException {
+    return this.position;
+  }
+
+  @Override
+  public SeekableByteChannel position(final long newPosition) throws IOException {
+    this.position = (int)newPosition;
+    return this;
+  }
+
+  @Override
+  public long size() throws IOException {
+    return this.byteArray.length;
+  }
+
+  @Override
+  public int write(final ByteBuffer src) throws IOException {
+    throw new UnsupportedOperationException("Read only");
+  }
+
+  @Override
+  public SeekableByteChannel truncate(final long size) throws IOException {
+    throw new UnsupportedOperationException("Read only");
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowFile.java
----------------------------------------------------------------------
diff --git a/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowFile.java b/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowFile.java
new file mode 100644
index 0000000..11de0a2
--- /dev/null
+++ b/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowFile.java
@@ -0,0 +1,331 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.List;
+
+import org.apache.arrow.memory.BufferAllocator;
+import org.apache.arrow.memory.RootAllocator;
+import org.apache.arrow.vector.FieldVector;
+import org.apache.arrow.vector.ValueVector.Accessor;
+import org.apache.arrow.vector.VectorLoader;
+import org.apache.arrow.vector.VectorUnloader;
+import org.apache.arrow.vector.complex.MapVector;
+import org.apache.arrow.vector.complex.impl.ComplexWriterImpl;
+import org.apache.arrow.vector.complex.impl.SingleMapReaderImpl;
+import org.apache.arrow.vector.complex.reader.BaseReader.MapReader;
+import org.apache.arrow.vector.complex.writer.BaseWriter.ComplexWriter;
+import org.apache.arrow.vector.complex.writer.BaseWriter.ListWriter;
+import org.apache.arrow.vector.complex.writer.BaseWriter.MapWriter;
+import org.apache.arrow.vector.complex.writer.BigIntWriter;
+import org.apache.arrow.vector.complex.writer.IntWriter;
+import org.apache.arrow.vector.schema.ArrowBuffer;
+import org.apache.arrow.vector.schema.ArrowRecordBatch;
+import org.apache.arrow.vector.types.Types.MinorType;
+import org.apache.arrow.vector.types.pojo.Schema;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import io.netty.buffer.ArrowBuf;
+
+public class TestArrowFile {
+  private static final int COUNT = 10;
+  private BufferAllocator allocator;
+
+  @Before
+  public void init() {
+    allocator = new RootAllocator(Integer.MAX_VALUE);
+  }
+
+  @After
+  public void tearDown() {
+    allocator.close();
+  }
+
+  @Test
+  public void testWrite() throws IOException {
+    File file = new File("target/mytest_write.arrow");
+    int count = COUNT;
+    try (
+        BufferAllocator vectorAllocator = allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", vectorAllocator, null)) {
+      writeData(count, parent);
+      write((MapVector)parent.getChild("root"), file);
+    }
+  }
+
+  @Test
+  public void testWriteComplex() throws IOException {
+    File file = new File("target/mytest_write_complex.arrow");
+    int count = COUNT;
+    try (
+        BufferAllocator vectorAllocator = allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", vectorAllocator, null)) {
+      writeComplexData(count, parent);
+      validateComplexContent(count, parent);
+      write((MapVector)parent.getChild("root"), file);
+    }
+  }
+
+  private void writeComplexData(int count, MapVector parent) {
+    ArrowBuf varchar = allocator.buffer(3);
+    varchar.readerIndex(0);
+    varchar.setByte(0, 'a');
+    varchar.setByte(1, 'b');
+    varchar.setByte(2, 'c');
+    varchar.writerIndex(3);
+    ComplexWriter writer = new ComplexWriterImpl("root", parent);
+    MapWriter rootWriter = writer.rootAsMap();
+    IntWriter intWriter = rootWriter.integer("int");
+    BigIntWriter bigIntWriter = rootWriter.bigInt("bigInt");
+    ListWriter listWriter = rootWriter.list("list");
+    MapWriter mapWriter = rootWriter.map("map");
+    for (int i = 0; i < count; i++) {
+      intWriter.setPosition(i);
+      intWriter.writeInt(i);
+      bigIntWriter.setPosition(i);
+      bigIntWriter.writeBigInt(i);
+      listWriter.setPosition(i);
+      listWriter.startList();
+      for (int j = 0; j < i % 3; j++) {
+        listWriter.varChar().writeVarChar(0, 3, varchar);
+      }
+      listWriter.endList();
+      mapWriter.setPosition(i);
+      mapWriter.start();
+      mapWriter.timeStamp("timestamp").writeTimeStamp(i);
+      mapWriter.end();
+    }
+    writer.setValueCount(count);
+    varchar.release();
+  }
+
+
+  private void writeData(int count, MapVector parent) {
+    ComplexWriter writer = new ComplexWriterImpl("root", parent);
+    MapWriter rootWriter = writer.rootAsMap();
+    IntWriter intWriter = rootWriter.integer("int");
+    BigIntWriter bigIntWriter = rootWriter.bigInt("bigInt");
+    for (int i = 0; i < count; i++) {
+      intWriter.setPosition(i);
+      intWriter.writeInt(i);
+      bigIntWriter.setPosition(i);
+      bigIntWriter.writeBigInt(i);
+    }
+    writer.setValueCount(count);
+  }
+
+  @Test
+  public void testWriteRead() throws IOException {
+    File file = new File("target/mytest.arrow");
+    int count = COUNT;
+
+    // write
+    try (
+        BufferAllocator originalVectorAllocator = allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", originalVectorAllocator, null)) {
+      writeData(count, parent);
+      write((MapVector)parent.getChild("root"), file);
+    }
+
+    // read
+    try (
+        BufferAllocator readerAllocator = allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
+        FileInputStream fileInputStream = new FileInputStream(file);
+        ArrowReader arrowReader = new ArrowReader(fileInputStream.getChannel(), readerAllocator);
+        BufferAllocator vectorAllocator = allocator.newChildAllocator("final vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", vectorAllocator, null)
+        ) {
+      ArrowFooter footer = arrowReader.readFooter();
+      Schema schema = footer.getSchema();
+      System.out.println("reading schema: " + schema);
+
+      // initialize vectors
+
+      MapVector root = parent.addOrGet("root", MinorType.MAP, MapVector.class);
+
+      VectorLoader vectorLoader = new VectorLoader(schema, root);
+
+      List<ArrowBlock> recordBatches = footer.getRecordBatches();
+      for (ArrowBlock rbBlock : recordBatches) {
+        Assert.assertEquals(0, rbBlock.getOffset() % 8);
+        Assert.assertEquals(0, rbBlock.getMetadataLength() % 8);
+        try (ArrowRecordBatch recordBatch = arrowReader.readRecordBatch(rbBlock)) {
+          List<ArrowBuffer> buffersLayout = recordBatch.getBuffersLayout();
+          for (ArrowBuffer arrowBuffer : buffersLayout) {
+            Assert.assertEquals(0, arrowBuffer.getOffset() % 8);
+          }
+          vectorLoader.load(recordBatch);
+        }
+
+        validateContent(count, parent);
+      }
+    }
+  }
+
+  private void validateContent(int count, MapVector parent) {
+    MapReader rootReader = new SingleMapReaderImpl(parent).reader("root");
+    for (int i = 0; i < count; i++) {
+      rootReader.setPosition(i);
+      Assert.assertEquals(i, rootReader.reader("int").readInteger().intValue());
+      Assert.assertEquals(i, rootReader.reader("bigInt").readLong().longValue());
+    }
+  }
+
+  @Test
+  public void testWriteReadComplex() throws IOException {
+    File file = new File("target/mytest_complex.arrow");
+    int count = COUNT;
+
+    // write
+    try (
+        BufferAllocator originalVectorAllocator = allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", originalVectorAllocator, null)) {
+      writeComplexData(count, parent);
+      write((MapVector)parent.getChild("root"), file);
+    }
+
+    // read
+    try (
+        BufferAllocator readerAllocator = allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
+        FileInputStream fileInputStream = new FileInputStream(file);
+        ArrowReader arrowReader = new ArrowReader(fileInputStream.getChannel(), readerAllocator);
+        BufferAllocator vectorAllocator = allocator.newChildAllocator("final vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", vectorAllocator, null)
+        ) {
+      ArrowFooter footer = arrowReader.readFooter();
+      Schema schema = footer.getSchema();
+      System.out.println("reading schema: " + schema);
+
+      // initialize vectors
+
+      MapVector root = parent.addOrGet("root", MinorType.MAP, MapVector.class);
+
+      VectorLoader vectorLoader = new VectorLoader(schema, root);
+
+      List<ArrowBlock> recordBatches = footer.getRecordBatches();
+      for (ArrowBlock rbBlock : recordBatches) {
+        try (ArrowRecordBatch recordBatch = arrowReader.readRecordBatch(rbBlock)) {
+          vectorLoader.load(recordBatch);
+        }
+        validateComplexContent(count, parent);
+      }
+    }
+  }
+
+  public void printVectors(List<FieldVector> vectors) {
+    for (FieldVector vector : vectors) {
+      System.out.println(vector.getField().getName());
+      Accessor accessor = vector.getAccessor();
+      int valueCount = accessor.getValueCount();
+      for (int i = 0; i < valueCount; i++) {
+        System.out.println(accessor.getObject(i));
+      }
+    }
+  }
+
+  private void validateComplexContent(int count, MapVector parent) {
+    printVectors(parent.getChildrenFromFields());
+
+    MapReader rootReader = new SingleMapReaderImpl(parent).reader("root");
+    for (int i = 0; i < count; i++) {
+      rootReader.setPosition(i);
+      Assert.assertEquals(i, rootReader.reader("int").readInteger().intValue());
+      Assert.assertEquals(i, rootReader.reader("bigInt").readLong().longValue());
+      Assert.assertEquals(i % 3, rootReader.reader("list").size());
+      Assert.assertEquals(i, rootReader.reader("map").reader("timestamp").readDateTime().getMillis() % COUNT);
+    }
+  }
+
+  private void write(MapVector parent, File file) throws FileNotFoundException, IOException {
+    VectorUnloader vectorUnloader = new VectorUnloader(parent);
+    Schema schema = vectorUnloader.getSchema();
+    System.out.println("writing schema: " + schema);
+    try (
+        FileOutputStream fileOutputStream = new FileOutputStream(file);
+        ArrowWriter arrowWriter = new ArrowWriter(fileOutputStream.getChannel(), schema);
+        ArrowRecordBatch recordBatch = vectorUnloader.getRecordBatch();
+            ) {
+      arrowWriter.writeRecordBatch(recordBatch);
+    }
+  }
+
+  @Test
+  public void testWriteReadMultipleRBs() throws IOException {
+    File file = new File("target/mytest_multiple.arrow");
+    int count = COUNT;
+
+    // write
+    try (
+        BufferAllocator originalVectorAllocator = allocator.newChildAllocator("original vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", originalVectorAllocator, null);
+        FileOutputStream fileOutputStream = new FileOutputStream(file);) {
+      writeData(count, parent);
+      VectorUnloader vectorUnloader = new VectorUnloader(parent.getChild("root"));
+      Schema schema = vectorUnloader.getSchema();
+      Assert.assertEquals(2, schema.getFields().size());
+      try (ArrowWriter arrowWriter = new ArrowWriter(fileOutputStream.getChannel(), schema);) {
+        try (ArrowRecordBatch recordBatch = vectorUnloader.getRecordBatch()) {
+          arrowWriter.writeRecordBatch(recordBatch);
+        }
+        parent.allocateNew();
+        writeData(count, parent);
+        try (ArrowRecordBatch recordBatch = vectorUnloader.getRecordBatch()) {
+          arrowWriter.writeRecordBatch(recordBatch);
+        }
+      }
+    }
+
+    // read
+    try (
+        BufferAllocator readerAllocator = allocator.newChildAllocator("reader", 0, Integer.MAX_VALUE);
+        FileInputStream fileInputStream = new FileInputStream(file);
+        ArrowReader arrowReader = new ArrowReader(fileInputStream.getChannel(), readerAllocator);
+        BufferAllocator vectorAllocator = allocator.newChildAllocator("final vectors", 0, Integer.MAX_VALUE);
+        MapVector parent = new MapVector("parent", vectorAllocator, null);
+        ) {
+      ArrowFooter footer = arrowReader.readFooter();
+      Schema schema = footer.getSchema();
+      System.out.println("reading schema: " + schema);
+      MapVector root = parent.addOrGet("root", MinorType.MAP, MapVector.class);
+      VectorLoader vectorLoader = new VectorLoader(schema, root);
+      List<ArrowBlock> recordBatches = footer.getRecordBatches();
+      Assert.assertEquals(2, recordBatches.size());
+      for (ArrowBlock rbBlock : recordBatches) {
+        Assert.assertEquals(0, rbBlock.getOffset() % 8);
+        Assert.assertEquals(0, rbBlock.getMetadataLength() % 8);
+        try (ArrowRecordBatch recordBatch = arrowReader.readRecordBatch(rbBlock)) {
+          List<ArrowBuffer> buffersLayout = recordBatch.getBuffersLayout();
+          for (ArrowBuffer arrowBuffer : buffersLayout) {
+            Assert.assertEquals(0, arrowBuffer.getOffset() % 8);
+          }
+          vectorLoader.load(recordBatch);
+          validateContent(count, parent);
+        }
+      }
+    }
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowFooter.java
----------------------------------------------------------------------
diff --git a/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowFooter.java b/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowFooter.java
new file mode 100644
index 0000000..707dba2
--- /dev/null
+++ b/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowFooter.java
@@ -0,0 +1,56 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+import static java.util.Arrays.asList;
+import static org.junit.Assert.assertEquals;
+
+import java.nio.ByteBuffer;
+import java.util.Collections;
+
+import org.apache.arrow.flatbuf.Footer;
+import org.apache.arrow.vector.types.pojo.ArrowType;
+import org.apache.arrow.vector.types.pojo.Field;
+import org.apache.arrow.vector.types.pojo.Schema;
+import org.junit.Test;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+public class TestArrowFooter {
+
+  @Test
+  public void test() {
+    Schema schema = new Schema(asList(
+        new Field("a", true, new ArrowType.Int(8, true), Collections.<Field>emptyList())
+        ));
+    ArrowFooter footer = new ArrowFooter(schema, Collections.<ArrowBlock>emptyList(), Collections.<ArrowBlock>emptyList());
+    ArrowFooter newFooter = roundTrip(footer);
+    assertEquals(footer, newFooter);
+  }
+
+
+  private ArrowFooter roundTrip(ArrowFooter footer) {
+    FlatBufferBuilder builder = new FlatBufferBuilder();
+    int i = footer.writeTo(builder);
+    builder.finish(i);
+    ByteBuffer dataBuffer = builder.dataBuffer();
+    ArrowFooter newFooter = new ArrowFooter(Footer.getRootAsFooter(dataBuffer));
+    return newFooter;
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowReaderWriter.java
----------------------------------------------------------------------
diff --git a/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowReaderWriter.java b/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowReaderWriter.java
new file mode 100644
index 0000000..f90329a
--- /dev/null
+++ b/java/vector/src/test/java/org/apache/arrow/vector/file/TestArrowReaderWriter.java
@@ -0,0 +1,106 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+import static java.util.Arrays.asList;
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.channels.Channels;
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.arrow.memory.BufferAllocator;
+import org.apache.arrow.memory.RootAllocator;
+import org.apache.arrow.vector.file.ArrowBlock;
+import org.apache.arrow.vector.file.ArrowFooter;
+import org.apache.arrow.vector.file.ArrowReader;
+import org.apache.arrow.vector.file.ArrowWriter;
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+import org.apache.arrow.vector.schema.ArrowRecordBatch;
+import org.apache.arrow.vector.types.pojo.ArrowType;
+import org.apache.arrow.vector.types.pojo.Field;
+import org.apache.arrow.vector.types.pojo.Schema;
+import org.junit.Before;
+import org.junit.Test;
+
+import io.netty.buffer.ArrowBuf;
+
+public class TestArrowReaderWriter {
+
+  private BufferAllocator allocator;
+
+  @Before
+  public void init() {
+    allocator = new RootAllocator(Long.MAX_VALUE);
+  }
+
+  ArrowBuf buf(byte[] bytes) {
+    ArrowBuf buffer = allocator.buffer(bytes.length);
+    buffer.writeBytes(bytes);
+    return buffer;
+  }
+
+  byte[] array(ArrowBuf buf) {
+    byte[] bytes = new byte[buf.readableBytes()];
+    buf.readBytes(bytes);
+    return bytes;
+  }
+
+  @Test
+  public void test() throws IOException {
+    Schema schema = new Schema(asList(new Field("testField", true, new ArrowType.Int(8, true), Collections.<Field>emptyList())));
+    byte[] validity = new byte[] { (byte)255, 0};
+    // second half is "undefined"
+    byte[] values = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
+
+    ByteArrayOutputStream out = new ByteArrayOutputStream();
+    try (ArrowWriter writer = new ArrowWriter(Channels.newChannel(out), schema)) {
+      ArrowBuf validityb = buf(validity);
+      ArrowBuf valuesb =  buf(values);
+      writer.writeRecordBatch(new ArrowRecordBatch(16, asList(new ArrowFieldNode(16, 8)), asList(validityb, valuesb)));
+    }
+
+    byte[] byteArray = out.toByteArray();
+
+    try (ArrowReader reader = new ArrowReader(new ByteArrayReadableSeekableByteChannel(byteArray), allocator)) {
+      ArrowFooter footer = reader.readFooter();
+      Schema readSchema = footer.getSchema();
+      assertEquals(schema, readSchema);
+      assertTrue(readSchema.getFields().get(0).getTypeLayout().getVectorTypes().toString(), readSchema.getFields().get(0).getTypeLayout().getVectors().size() > 0);
+      // TODO: dictionaries
+      List<ArrowBlock> recordBatches = footer.getRecordBatches();
+      assertEquals(1, recordBatches.size());
+      ArrowRecordBatch recordBatch = reader.readRecordBatch(recordBatches.get(0));
+      List<ArrowFieldNode> nodes = recordBatch.getNodes();
+      assertEquals(1, nodes.size());
+      ArrowFieldNode node = nodes.get(0);
+      assertEquals(16, node.getLength());
+      assertEquals(8, node.getNullCount());
+      List<ArrowBuf> buffers = recordBatch.getBuffers();
+      assertEquals(2, buffers.size());
+      assertArrayEquals(validity, array(buffers.get(0)));
+      assertArrayEquals(values, array(buffers.get(1)));
+
+    }
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/test/java/org/apache/arrow/vector/pojo/TestConvert.java
----------------------------------------------------------------------
diff --git a/java/vector/src/test/java/org/apache/arrow/vector/pojo/TestConvert.java b/java/vector/src/test/java/org/apache/arrow/vector/pojo/TestConvert.java
index 06a1149..61327f1 100644
--- a/java/vector/src/test/java/org/apache/arrow/vector/pojo/TestConvert.java
+++ b/java/vector/src/test/java/org/apache/arrow/vector/pojo/TestConvert.java
@@ -17,19 +17,24 @@
  */
 package org.apache.arrow.vector.pojo;
 
-import com.google.common.collect.ImmutableList;
-import com.google.flatbuffers.FlatBufferBuilder;
+import static org.apache.arrow.flatbuf.Precision.DOUBLE;
+import static org.apache.arrow.flatbuf.Precision.SINGLE;
+import static org.junit.Assert.assertEquals;
+
+import org.apache.arrow.flatbuf.UnionMode;
 import org.apache.arrow.vector.types.pojo.ArrowType.FloatingPoint;
 import org.apache.arrow.vector.types.pojo.ArrowType.Int;
+import org.apache.arrow.vector.types.pojo.ArrowType.List;
+import org.apache.arrow.vector.types.pojo.ArrowType.Timestamp;
 import org.apache.arrow.vector.types.pojo.ArrowType.Tuple;
+import org.apache.arrow.vector.types.pojo.ArrowType.Union;
 import org.apache.arrow.vector.types.pojo.ArrowType.Utf8;
 import org.apache.arrow.vector.types.pojo.Field;
 import org.apache.arrow.vector.types.pojo.Schema;
 import org.junit.Test;
 
-import java.util.List;
-
-import static org.junit.Assert.assertEquals;
+import com.google.common.collect.ImmutableList;
+import com.google.flatbuffers.FlatBufferBuilder;
 
 /**
  * Test conversion between Flatbuf and Pojo field representations
@@ -46,7 +51,7 @@ public class TestConvert {
   public void complex() {
     ImmutableList.Builder<Field> childrenBuilder = ImmutableList.builder();
     childrenBuilder.add(new Field("child1", true, Utf8.INSTANCE, null));
-    childrenBuilder.add(new Field("child2", true, new FloatingPoint(0), ImmutableList.<Field>of()));
+    childrenBuilder.add(new Field("child2", true, new FloatingPoint(SINGLE), ImmutableList.<Field>of()));
 
     Field initialField = new Field("a", true, Tuple.INSTANCE, childrenBuilder.build());
     run(initialField);
@@ -56,10 +61,29 @@ public class TestConvert {
   public void schema() {
     ImmutableList.Builder<Field> childrenBuilder = ImmutableList.builder();
     childrenBuilder.add(new Field("child1", true, Utf8.INSTANCE, null));
-    childrenBuilder.add(new Field("child2", true, new FloatingPoint(0), ImmutableList.<Field>of()));
+    childrenBuilder.add(new Field("child2", true, new FloatingPoint(SINGLE), ImmutableList.<Field>of()));
     Schema initialSchema = new Schema(childrenBuilder.build());
     run(initialSchema);
+  }
 
+  @Test
+  public void nestedSchema() {
+    ImmutableList.Builder<Field> childrenBuilder = ImmutableList.builder();
+    childrenBuilder.add(new Field("child1", true, Utf8.INSTANCE, null));
+    childrenBuilder.add(new Field("child2", true, new FloatingPoint(SINGLE), ImmutableList.<Field>of()));
+    childrenBuilder.add(new Field("child3", true, new Tuple(), ImmutableList.<Field>of(
+        new Field("child3.1", true, Utf8.INSTANCE, null),
+        new Field("child3.2", true, new FloatingPoint(DOUBLE), ImmutableList.<Field>of())
+        )));
+    childrenBuilder.add(new Field("child4", true, new List(), ImmutableList.<Field>of(
+        new Field("child4.1", true, Utf8.INSTANCE, null)
+        )));
+    childrenBuilder.add(new Field("child5", true, new Union(UnionMode.Sparse), ImmutableList.<Field>of(
+        new Field("child5.1", true, new Timestamp("UTC"), null),
+        new Field("child5.2", true, new FloatingPoint(DOUBLE), ImmutableList.<Field>of())
+        )));
+    Schema initialSchema = new Schema(childrenBuilder.build());
+    run(initialSchema);
   }
 
   private void run(Field initialField) {


[2/2] arrow git commit: ARROW-264: File format

Posted by ju...@apache.org.
ARROW-264: File format

This is work in progress

Author: Julien Le Dem <ju...@dremio.com>

Closes #123 from julienledem/arrow_264_file_format and squashes the following commits:

252de6d [Julien Le Dem] remove outdated comment
04d797f [Julien Le Dem] maps are not nullable yet
e8359b3 [Julien Le Dem] align on 8 byte boundaries; more tests
8b8b823 [Julien Le Dem] refactoring
31e95e6 [Julien Le Dem] fix list vector
b824938 [Julien Le Dem] fix types; add licenses; more tests; more complex
2fd3bc1 [Julien Le Dem] cleanup
50fe680 [Julien Le Dem] nested support
b0bf6bc [Julien Le Dem] cleanup
4247b1a [Julien Le Dem] fix whitespace
d6a1788 [Julien Le Dem] refactoring
81863c5 [Julien Le Dem] fixed loader
aa1b766 [Julien Le Dem] better test
2067e01 [Julien Le Dem] update format
aacf61e [Julien Le Dem] fix pom
b907aa5 [Julien Le Dem] simplify
e43f26b [Julien Le Dem] add layout spec
0cc9718 [Julien Le Dem] add vector type
ac6902a [Julien Le Dem] ARROW-264: File format
807db51 [Julien Le Dem] move information to schema
f2f0596 [Julien Le Dem] Update FieldNode structure to be more explicit and reflect schema


Project: http://git-wip-us.apache.org/repos/asf/arrow/repo
Commit: http://git-wip-us.apache.org/repos/asf/arrow/commit/803afeb5
Tree: http://git-wip-us.apache.org/repos/asf/arrow/tree/803afeb5
Diff: http://git-wip-us.apache.org/repos/asf/arrow/diff/803afeb5

Branch: refs/heads/master
Commit: 803afeb502dcdd802fada2ed0d66c145546b8a78
Parents: ec51d56
Author: Julien Le Dem <ju...@dremio.com>
Authored: Fri Aug 26 08:20:13 2016 -0700
Committer: Julien Le Dem <ju...@dremio.com>
Committed: Fri Aug 26 08:20:13 2016 -0700

----------------------------------------------------------------------
 cpp/src/arrow/ipc/metadata-internal.cc          |   1 +
 format/File.fbs                                 |  28 ++
 format/Message.fbs                              |  21 +-
 java/format/pom.xml                             |   1 +
 .../src/main/java/io/netty/buffer/ArrowBuf.java |  71 ++--
 .../vector/src/main/codegen/data/ArrowTypes.tdd |   4 +-
 .../src/main/codegen/templates/ArrowType.java   |  29 +-
 .../codegen/templates/NullableValueVectors.java |  49 ++-
 .../src/main/codegen/templates/UnionVector.java |  40 ++-
 .../arrow/vector/BaseDataValueVector.java       |  38 ++-
 .../org/apache/arrow/vector/BufferBacked.java   |  31 ++
 .../org/apache/arrow/vector/FieldVector.java    |  65 ++++
 .../org/apache/arrow/vector/ValueVector.java    |   6 +-
 .../org/apache/arrow/vector/VectorLoader.java   |  99 ++++++
 .../org/apache/arrow/vector/VectorUnloader.java |  78 +++++
 .../org/apache/arrow/vector/ZeroVector.java     |  39 ++-
 .../vector/complex/AbstractContainerVector.java |  21 +-
 .../arrow/vector/complex/AbstractMapVector.java |  42 ++-
 .../vector/complex/BaseRepeatedValueVector.java |  21 +-
 .../apache/arrow/vector/complex/ListVector.java |  58 +++-
 .../apache/arrow/vector/complex/MapVector.java  |  59 +++-
 .../vector/complex/impl/ComplexWriterImpl.java  |   2 +-
 .../vector/complex/impl/PromotableWriter.java   |   3 +-
 .../apache/arrow/vector/file/ArrowBlock.java    |  82 +++++
 .../apache/arrow/vector/file/ArrowFooter.java   | 144 ++++++++
 .../apache/arrow/vector/file/ArrowReader.java   | 151 +++++++++
 .../apache/arrow/vector/file/ArrowWriter.java   | 179 ++++++++++
 .../vector/file/InvalidArrowFileException.java  |  27 ++
 .../apache/arrow/vector/schema/ArrowBuffer.java |  81 +++++
 .../arrow/vector/schema/ArrowFieldNode.java     |  53 +++
 .../arrow/vector/schema/ArrowRecordBatch.java   | 127 +++++++
 .../arrow/vector/schema/ArrowVectorType.java    |  47 +++
 .../arrow/vector/schema/FBSerializable.java     |  24 ++
 .../arrow/vector/schema/FBSerializables.java    |  37 +++
 .../apache/arrow/vector/schema/TypeLayout.java  | 208 ++++++++++++
 .../arrow/vector/schema/VectorLayout.java       |  93 ++++++
 .../org/apache/arrow/vector/types/Types.java    |  70 ++--
 .../apache/arrow/vector/types/pojo/Field.java   |  42 ++-
 .../apache/arrow/vector/types/pojo/Schema.java  |  13 +-
 .../arrow/vector/TestVectorUnloadLoad.java      |  89 +++++
 .../ByteArrayReadableSeekableByteChannel.java   |  80 +++++
 .../apache/arrow/vector/file/TestArrowFile.java | 331 +++++++++++++++++++
 .../arrow/vector/file/TestArrowFooter.java      |  56 ++++
 .../vector/file/TestArrowReaderWriter.java      | 106 ++++++
 .../apache/arrow/vector/pojo/TestConvert.java   |  38 ++-
 45 files changed, 2722 insertions(+), 162 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/cpp/src/arrow/ipc/metadata-internal.cc
----------------------------------------------------------------------
diff --git a/cpp/src/arrow/ipc/metadata-internal.cc b/cpp/src/arrow/ipc/metadata-internal.cc
index 50db730..c921e4d 100644
--- a/cpp/src/arrow/ipc/metadata-internal.cc
+++ b/cpp/src/arrow/ipc/metadata-internal.cc
@@ -219,6 +219,7 @@ static Status FieldToFlatbuffer(
   RETURN_NOT_OK(TypeToFlatbuffer(fbb, field->type, &children, &type_enum, &type_data));
   auto fb_children = fbb.CreateVector(children);
 
+  // TODO: produce the list of VectorTypes
   *offset = flatbuf::CreateField(
       fbb, fb_name, field->nullable, type_enum, type_data, field->dictionary,
       fb_children);

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/format/File.fbs
----------------------------------------------------------------------
diff --git a/format/File.fbs b/format/File.fbs
new file mode 100644
index 0000000..f7ad1e1
--- /dev/null
+++ b/format/File.fbs
@@ -0,0 +1,28 @@
+include "Message.fbs";
+
+namespace org.apache.arrow.flatbuf;
+
+/// ----------------------------------------------------------------------
+/// Arrow File metadata
+///
+
+table Footer {
+
+  schema: org.apache.arrow.flatbuf.Schema;
+
+  dictionaries: [ Block ];
+
+  recordBatches: [ Block ];
+}
+
+struct Block {
+
+  offset: long;
+
+  metaDataLength: int;
+
+  bodyLength: long;
+
+}
+
+root_type Footer;

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/format/Message.fbs
----------------------------------------------------------------------
diff --git a/format/Message.fbs b/format/Message.fbs
index a78009b..b02f3fa 100644
--- a/format/Message.fbs
+++ b/format/Message.fbs
@@ -17,7 +17,7 @@ table Tuple {
 table List {
 }
 
-enum UnionMode:int { Sparse, Dense }
+enum UnionMode:short { Sparse, Dense }
 
 table Union {
   mode: UnionMode;
@@ -28,7 +28,7 @@ table Int {
   is_signed: bool;
 }
 
-enum Precision:int {SINGLE, DOUBLE}
+enum Precision:short {SINGLE, DOUBLE}
 
 table FloatingPoint {
   precision: Precision;
@@ -91,6 +91,17 @@ union Type {
   JSONScalar
 }
 
+enum VectorType: short {
+  /// used in List type Dense Union and variable length primitive types (String, Binary)
+  OFFSET,
+  /// fixed length primitive values
+  VALUES,
+  /// Bit vector indicated if each value is null
+  VALIDITY,
+  /// Type vector used in Union type
+  TYPE
+}
+
 /// ----------------------------------------------------------------------
 /// A field represents a named column in a record / row batch or child of a
 /// nested type.
@@ -109,12 +120,16 @@ table Field {
   dictionary: long;
   // children apply only to Nested data types like Struct, List and Union
   children: [Field];
+  /// the buffers produced for this type (as derived from the Type)
+  /// does not include children
+  /// each recordbatch will return instances of those Buffers.
+  buffers: [ VectorType ];
 }
 
 /// ----------------------------------------------------------------------
 /// Endianness of the platform that produces the RecordBatch
 
-enum Endianness:int { Little, Big }
+enum Endianness:short { Little, Big }
 
 /// ----------------------------------------------------------------------
 /// A Schema describes the columns in a row batch

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/format/pom.xml
----------------------------------------------------------------------
diff --git a/java/format/pom.xml b/java/format/pom.xml
index cb11b5f..dc58975 100644
--- a/java/format/pom.xml
+++ b/java/format/pom.xml
@@ -106,6 +106,7 @@
               <argument>-o</argument>
               <argument>target/generated-sources/</argument>
               <argument>../../format/Message.fbs</argument>
+              <argument>../../format/File.fbs</argument>
             </arguments>
           </configuration>
         </execution>

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/memory/src/main/java/io/netty/buffer/ArrowBuf.java
----------------------------------------------------------------------
diff --git a/java/memory/src/main/java/io/netty/buffer/ArrowBuf.java b/java/memory/src/main/java/io/netty/buffer/ArrowBuf.java
index bbec26a..d10f002 100644
--- a/java/memory/src/main/java/io/netty/buffer/ArrowBuf.java
+++ b/java/memory/src/main/java/io/netty/buffer/ArrowBuf.java
@@ -17,8 +17,6 @@
  */
 package io.netty.buffer;
 
-import io.netty.util.internal.PlatformDependent;
-
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -30,16 +28,18 @@ import java.nio.charset.Charset;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
 
+import org.apache.arrow.memory.AllocationManager.BufferLedger;
 import org.apache.arrow.memory.BaseAllocator;
+import org.apache.arrow.memory.BaseAllocator.Verbosity;
 import org.apache.arrow.memory.BoundsChecking;
 import org.apache.arrow.memory.BufferAllocator;
 import org.apache.arrow.memory.BufferManager;
-import org.apache.arrow.memory.AllocationManager.BufferLedger;
-import org.apache.arrow.memory.BaseAllocator.Verbosity;
 import org.apache.arrow.memory.util.HistoricalLog;
 
 import com.google.common.base.Preconditions;
 
+import io.netty.util.internal.PlatformDependent;
+
 public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(ArrowBuf.class);
 
@@ -307,7 +307,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf order(ByteOrder endianness) {
+  public ArrowBuf order(ByteOrder endianness) {
     return this;
   }
 
@@ -344,7 +344,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf slice() {
+  public ArrowBuf slice() {
     return slice(readerIndex(), readableBytes());
   }
 
@@ -467,7 +467,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf retain(int increment) {
+  public ArrowBuf retain(int increment) {
     Preconditions.checkArgument(increment > 0, "retain(%d) argument is not positive", increment);
 
     if (isEmpty) {
@@ -484,7 +484,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf retain() {
+  public ArrowBuf retain() {
     return retain(1);
   }
 
@@ -535,49 +535,49 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf setShort(int index, int value) {
+  public ArrowBuf setShort(int index, int value) {
     chk(index, 2);
     PlatformDependent.putShort(addr(index), (short) value);
     return this;
   }
 
   @Override
-  public ByteBuf setInt(int index, int value) {
+  public ArrowBuf setInt(int index, int value) {
     chk(index, 4);
     PlatformDependent.putInt(addr(index), value);
     return this;
   }
 
   @Override
-  public ByteBuf setLong(int index, long value) {
+  public ArrowBuf setLong(int index, long value) {
     chk(index, 8);
     PlatformDependent.putLong(addr(index), value);
     return this;
   }
 
   @Override
-  public ByteBuf setChar(int index, int value) {
+  public ArrowBuf setChar(int index, int value) {
     chk(index, 2);
     PlatformDependent.putShort(addr(index), (short) value);
     return this;
   }
 
   @Override
-  public ByteBuf setFloat(int index, float value) {
+  public ArrowBuf setFloat(int index, float value) {
     chk(index, 4);
     PlatformDependent.putInt(addr(index), Float.floatToRawIntBits(value));
     return this;
   }
 
   @Override
-  public ByteBuf setDouble(int index, double value) {
+  public ArrowBuf setDouble(int index, double value) {
     chk(index, 8);
     PlatformDependent.putLong(addr(index), Double.doubleToRawLongBits(value));
     return this;
   }
 
   @Override
-  public ByteBuf writeShort(int value) {
+  public ArrowBuf writeShort(int value) {
     ensure(2);
     PlatformDependent.putShort(addr(writerIndex), (short) value);
     writerIndex += 2;
@@ -585,7 +585,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf writeInt(int value) {
+  public ArrowBuf writeInt(int value) {
     ensure(4);
     PlatformDependent.putInt(addr(writerIndex), value);
     writerIndex += 4;
@@ -593,7 +593,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf writeLong(long value) {
+  public ArrowBuf writeLong(long value) {
     ensure(8);
     PlatformDependent.putLong(addr(writerIndex), value);
     writerIndex += 8;
@@ -601,7 +601,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf writeChar(int value) {
+  public ArrowBuf writeChar(int value) {
     ensure(2);
     PlatformDependent.putShort(addr(writerIndex), (short) value);
     writerIndex += 2;
@@ -609,7 +609,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf writeFloat(float value) {
+  public ArrowBuf writeFloat(float value) {
     ensure(4);
     PlatformDependent.putInt(addr(writerIndex), Float.floatToRawIntBits(value));
     writerIndex += 4;
@@ -617,7 +617,7 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf writeDouble(double value) {
+  public ArrowBuf writeDouble(double value) {
     ensure(8);
     PlatformDependent.putLong(addr(writerIndex), Double.doubleToRawLongBits(value));
     writerIndex += 8;
@@ -625,19 +625,19 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf getBytes(int index, byte[] dst, int dstIndex, int length) {
+  public ArrowBuf getBytes(int index, byte[] dst, int dstIndex, int length) {
     udle.getBytes(index + offset, dst, dstIndex, length);
     return this;
   }
 
   @Override
-  public ByteBuf getBytes(int index, ByteBuffer dst) {
+  public ArrowBuf getBytes(int index, ByteBuffer dst) {
     udle.getBytes(index + offset, dst);
     return this;
   }
 
   @Override
-  public ByteBuf setByte(int index, int value) {
+  public ArrowBuf setByte(int index, int value) {
     chk(index, 1);
     PlatformDependent.putByte(addr(index), (byte) value);
     return this;
@@ -699,13 +699,13 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf getBytes(int index, ByteBuf dst, int dstIndex, int length) {
+  public ArrowBuf getBytes(int index, ByteBuf dst, int dstIndex, int length) {
     udle.getBytes(index + offset, dst, dstIndex, length);
     return this;
   }
 
   @Override
-  public ByteBuf getBytes(int index, OutputStream out, int length) throws IOException {
+  public ArrowBuf getBytes(int index, OutputStream out, int length) throws IOException {
     udle.getBytes(index + offset, out, length);
     return this;
   }
@@ -724,12 +724,12 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf setBytes(int index, ByteBuf src, int srcIndex, int length) {
+  public ArrowBuf setBytes(int index, ByteBuf src, int srcIndex, int length) {
     udle.setBytes(index + offset, src, srcIndex, length);
     return this;
   }
 
-  public ByteBuf setBytes(int index, ByteBuffer src, int srcIndex, int length) {
+  public ArrowBuf setBytes(int index, ByteBuffer src, int srcIndex, int length) {
     if (src.isDirect()) {
       checkIndex(index, length);
       PlatformDependent.copyMemory(PlatformDependent.directBufferAddress(src) + srcIndex, this.memoryAddress() + index,
@@ -749,13 +749,13 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
   }
 
   @Override
-  public ByteBuf setBytes(int index, byte[] src, int srcIndex, int length) {
+  public ArrowBuf setBytes(int index, byte[] src, int srcIndex, int length) {
     udle.setBytes(index + offset, src, srcIndex, length);
     return this;
   }
 
   @Override
-  public ByteBuf setBytes(int index, ByteBuffer src) {
+  public ArrowBuf setBytes(int index, ByteBuffer src) {
     udle.setBytes(index + offset, src);
     return this;
   }
@@ -860,4 +860,17 @@ public final class ArrowBuf extends AbstractByteBuf implements AutoCloseable {
     }
   }
 
+  @Override
+  public ArrowBuf readerIndex(int readerIndex) {
+    super.readerIndex(readerIndex);
+    return this;
+  }
+
+  @Override
+  public ArrowBuf writerIndex(int writerIndex) {
+    super.writerIndex(writerIndex);
+    return this;
+  }
+
+
 }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/codegen/data/ArrowTypes.tdd
----------------------------------------------------------------------
diff --git a/java/vector/src/main/codegen/data/ArrowTypes.tdd b/java/vector/src/main/codegen/data/ArrowTypes.tdd
index 4ab7f85..2ecad3d 100644
--- a/java/vector/src/main/codegen/data/ArrowTypes.tdd
+++ b/java/vector/src/main/codegen/data/ArrowTypes.tdd
@@ -30,7 +30,7 @@
     },
     {
       name: "Union",
-      fields: []
+      fields: [{name: "mode", type: short}]
     },
     {
       name: "Int",
@@ -38,7 +38,7 @@
     },
     {
       name: "FloatingPoint",
-      fields: [{name: precision, type: int}]
+      fields: [{name: precision, type: short}]
     },
     {
       name: "Utf8",

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/codegen/templates/ArrowType.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/codegen/templates/ArrowType.java b/java/vector/src/main/codegen/templates/ArrowType.java
index 6dfaf21..29dee20 100644
--- a/java/vector/src/main/codegen/templates/ArrowType.java
+++ b/java/vector/src/main/codegen/templates/ArrowType.java
@@ -24,9 +24,8 @@ import java.util.Objects;
 
 <@pp.dropOutputFile />
 <@pp.changeOutputFile name="/org/apache/arrow/vector/types/pojo/ArrowType.java" />
-
-
 <#include "/@includes/license.ftl" />
+
 package org.apache.arrow.vector.types.pojo;
 
 import com.google.flatbuffers.FlatBufferBuilder;
@@ -38,7 +37,13 @@ public abstract class ArrowType {
 
   public abstract byte getTypeType();
   public abstract int getType(FlatBufferBuilder builder);
+  public abstract <T> T accept(ArrowTypeVisitor<T> visitor);
 
+  public static interface ArrowTypeVisitor<T> {
+  <#list arrowTypes.types as type>
+    T visit(${type.name} type);
+  </#list>
+  }
 
   <#list arrowTypes.types as type>
   <#assign name = type.name>
@@ -70,9 +75,14 @@ public abstract class ArrowType {
 
     @Override
     public int getType(FlatBufferBuilder builder) {
+      <#list type.fields as field>
+      <#if field.type == "String">
+      int ${field.name} = builder.createString(this.${field.name});
+      </#if>
+      </#list>
       org.apache.arrow.flatbuf.${type.name}.start${type.name}(builder);
       <#list type.fields as field>
-      org.apache.arrow.flatbuf.${type.name}.add${field.name?cap_first}(builder, <#if field.type == "String">builder.createString(${field.name})<#else>${field.name}</#if>);
+      org.apache.arrow.flatbuf.${type.name}.add${field.name?cap_first}(builder, ${field.name});
       </#list>
       return org.apache.arrow.flatbuf.${type.name}.end${type.name}(builder);
     }
@@ -83,6 +93,14 @@ public abstract class ArrowType {
     }
     </#list>
 
+    public String toString() {
+      return "${name}{"
+      <#list fields as field>
+      + ", " + ${field.name}
+      </#list>
+      + "}";
+    }
+
     @Override
     public int hashCode() {
       return Objects.hash(<#list type.fields as field>${field.name}<#if field_has_next>, </#if></#list>);
@@ -102,6 +120,11 @@ public abstract class ArrowType {
       </#list>
       </#if>
     }
+
+    @Override
+    public <T> T accept(ArrowTypeVisitor<T> visitor) {
+      return visitor.visit(this);
+    }
   }
   </#list>
 

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/codegen/templates/NullableValueVectors.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/codegen/templates/NullableValueVectors.java b/java/vector/src/main/codegen/templates/NullableValueVectors.java
index df50897..6b1aa04 100644
--- a/java/vector/src/main/codegen/templates/NullableValueVectors.java
+++ b/java/vector/src/main/codegen/templates/NullableValueVectors.java
@@ -29,6 +29,9 @@
 
 package org.apache.arrow.vector;
 
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+import java.util.Collections;
+
 <#include "/@includes/vv_imports.ftl" />
 
 /**
@@ -39,7 +42,7 @@ package org.apache.arrow.vector;
  * NB: this class is automatically generated from ${.template_name} and ValueVectorTypes.tdd using FreeMarker.
  */
 @SuppressWarnings("unused")
-public final class ${className} extends BaseDataValueVector implements <#if type.major == "VarLen">VariableWidth<#else>FixedWidth</#if>Vector, NullableVector{
+public final class ${className} extends BaseDataValueVector implements <#if type.major == "VarLen">VariableWidth<#else>FixedWidth</#if>Vector, NullableVector, FieldVector {
   private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(${className}.class);
 
   private final FieldReader reader = new ${minor.class}ReaderImpl(Nullable${minor.class}Vector.this);
@@ -54,6 +57,8 @@ public final class ${className} extends BaseDataValueVector implements <#if type
   private final Mutator mutator;
   private final Accessor accessor;
 
+  private final List<BufferBacked> innerVectors;
+
   <#if minor.class == "Decimal">
   private final int precision;
   private final int scale;
@@ -66,6 +71,10 @@ public final class ${className} extends BaseDataValueVector implements <#if type
     mutator = new Mutator();
     accessor = new Accessor();
     field = new Field(name, true, new Decimal(precision, scale), null);
+    innerVectors = Collections.unmodifiableList(Arrays.<BufferBacked>asList(
+        bits,
+        values
+    ));
   }
   <#else>
   public ${className}(String name, BufferAllocator allocator) {
@@ -88,9 +97,9 @@ public final class ${className} extends BaseDataValueVector implements <#if type
   <#elseif minor.class == "Time">
     field = new Field(name, true, new org.apache.arrow.vector.types.pojo.ArrowType.Time(), null);
   <#elseif minor.class == "Float4">
-    field = new Field(name, true, new FloatingPoint(0), null);
+    field = new Field(name, true, new FloatingPoint(org.apache.arrow.flatbuf.Precision.SINGLE), null);
   <#elseif minor.class == "Float8">
-    field = new Field(name, true, new FloatingPoint(1), null);
+    field = new Field(name, true, new FloatingPoint(org.apache.arrow.flatbuf.Precision.DOUBLE), null);
   <#elseif minor.class == "TimeStamp">
     field = new Field(name, true, new org.apache.arrow.vector.types.pojo.ArrowType.Timestamp(""), null);
   <#elseif minor.class == "IntervalDay">
@@ -104,10 +113,44 @@ public final class ${className} extends BaseDataValueVector implements <#if type
   <#elseif minor.class == "Bit">
     field = new Field(name, true, new Bool(), null);
   </#if>
+    innerVectors = Collections.unmodifiableList(Arrays.<BufferBacked>asList(
+        bits,
+        <#if type.major = "VarLen">
+        values.offsetVector,
+        </#if>
+        values
+    ));
   }
   </#if>
 
   @Override
+  public List<BufferBacked> getFieldInnerVectors() {
+    return innerVectors;
+  }
+
+  @Override
+  public void initializeChildrenFromFields(List<Field> children) {
+    if (!children.isEmpty()) {
+      throw new IllegalArgumentException("primitive type vector ${className} can not have children: " + children);
+    }
+  }
+
+  @Override
+  public List<FieldVector> getChildrenFromFields() {
+    return Collections.emptyList();
+  }
+
+  @Override
+  public void loadFieldBuffers(ArrowFieldNode fieldNode, List<ArrowBuf> ownBuffers) {
+    org.apache.arrow.vector.BaseDataValueVector.load(getFieldInnerVectors(), ownBuffers);
+    // TODO: do something with the sizes in fieldNode?
+  }
+
+  public List<ArrowBuf> getFieldBuffers() {
+    return org.apache.arrow.vector.BaseDataValueVector.unload(getFieldInnerVectors());
+  }
+
+  @Override
   public Field getField() {
     return field;
   }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/codegen/templates/UnionVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/codegen/templates/UnionVector.java b/java/vector/src/main/codegen/templates/UnionVector.java
index 1fef490..72125fa 100644
--- a/java/vector/src/main/codegen/templates/UnionVector.java
+++ b/java/vector/src/main/codegen/templates/UnionVector.java
@@ -42,6 +42,10 @@ import java.util.ArrayList;
 import java.util.Iterator;
 import org.apache.arrow.vector.complex.impl.ComplexCopier;
 import org.apache.arrow.vector.util.CallBack;
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+
+import static org.apache.arrow.flatbuf.UnionMode.Sparse;
+
 
 /*
  * This class is generated using freemarker and the ${.template_name} template.
@@ -57,7 +61,7 @@ import org.apache.arrow.vector.util.CallBack;
  * For performance reasons, UnionVector stores a cached reference to each subtype vector, to avoid having to do the map lookup
  * each time the vector is accessed.
  */
-public class UnionVector implements ValueVector {
+public class UnionVector implements FieldVector {
 
   private String name;
   private BufferAllocator allocator;
@@ -95,6 +99,34 @@ public class UnionVector implements ValueVector {
     return MinorType.UNION;
   }
 
+  @Override
+  public void initializeChildrenFromFields(List<Field> children) {
+    getMap().initializeChildrenFromFields(children);
+  }
+
+  @Override
+  public List<FieldVector> getChildrenFromFields() {
+    return getMap().getChildrenFromFields();
+  }
+
+  @Override
+  public void loadFieldBuffers(ArrowFieldNode fieldNode, List<ArrowBuf> ownBuffers) {
+    // TODO
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public List<ArrowBuf> getFieldBuffers() {
+    // TODO
+    throw new UnsupportedOperationException();
+  }
+
+  @Override
+  public List<BufferBacked> getFieldInnerVectors() {
+    // TODO
+    throw new UnsupportedOperationException();
+  }
+  
   public MapVector getMap() {
     if (mapVector == null) {
       int vectorCount = internalMap.size();
@@ -203,7 +235,7 @@ public class UnionVector implements ValueVector {
     for (ValueVector v : internalMap.getChildren()) {
       childFields.add(v.getField());
     }
-    return new Field(name, true, new ArrowType.Union(), childFields);
+    return new Field(name, true, new ArrowType.Union(Sparse), childFields);
   }
 
   @Override
@@ -237,10 +269,10 @@ public class UnionVector implements ValueVector {
     copyFrom(inIndex, outIndex, from);
   }
 
-  public ValueVector addVector(ValueVector v) {
+  public FieldVector addVector(FieldVector v) {
     String name = v.getMinorType().name().toLowerCase();
     Preconditions.checkState(internalMap.getChild(name) == null, String.format("%s vector already exists", name));
-    final ValueVector newVector = internalMap.addOrGet(name, v.getMinorType(), v.getClass());
+    final FieldVector newVector = internalMap.addOrGet(name, v.getMinorType(), v.getClass());
     v.makeTransferPair(newVector).transfer();
     internalMap.putChild(name, newVector);
     if (callBack != null) {

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/BaseDataValueVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/BaseDataValueVector.java b/java/vector/src/main/java/org/apache/arrow/vector/BaseDataValueVector.java
index 05b7cf1..c22258d 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/BaseDataValueVector.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/BaseDataValueVector.java
@@ -17,15 +17,38 @@
  */
 package org.apache.arrow.vector;
 
-import io.netty.buffer.ArrowBuf;
+import java.util.ArrayList;
+import java.util.List;
 
 import org.apache.arrow.memory.BufferAllocator;
 
+import io.netty.buffer.ArrowBuf;
+
 
-public abstract class BaseDataValueVector extends BaseValueVector {
+public abstract class BaseDataValueVector extends BaseValueVector implements BufferBacked {
 
   protected final static byte[] emptyByteArray = new byte[]{}; // Nullable vectors use this
 
+  public static void load(List<BufferBacked> vectors, List<ArrowBuf> buffers) {
+    int expectedSize = vectors.size();
+    if (buffers.size() != expectedSize) {
+      throw new IllegalArgumentException("Illegal buffer count, expected " + expectedSize + ", got: " + buffers.size());
+    }
+    for (int i = 0; i < expectedSize; i++) {
+      vectors.get(i).load(buffers.get(i));
+    }
+  }
+
+  public static List<ArrowBuf> unload(List<BufferBacked> vectors) {
+    List<ArrowBuf> result = new ArrayList<>(vectors.size());
+    for (BufferBacked vector : vectors) {
+      result.add(vector.unLoad());
+    }
+    return result;
+  }
+
+  // TODO: Nullable vectors extend BaseDataValueVector but do not use the data field
+  // We should fix the inheritance tree
   protected ArrowBuf data;
 
   public BaseDataValueVector(String name, BufferAllocator allocator) {
@@ -82,6 +105,17 @@ public abstract class BaseDataValueVector extends BaseValueVector {
     return data;
   }
 
+  @Override
+  public void load(ArrowBuf data) {
+    this.data.release();
+    this.data = data.retain(allocator);
+  }
+
+  @Override
+  public ArrowBuf unLoad() {
+    return this.data.readerIndex(0);
+  }
+
   /**
    * This method has a similar effect of allocateNew() without actually clearing and reallocating
    * the value vector. The purpose is to move the value vector to a "mutate" state

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/BufferBacked.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/BufferBacked.java b/java/vector/src/main/java/org/apache/arrow/vector/BufferBacked.java
new file mode 100644
index 0000000..d1c262d
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/BufferBacked.java
@@ -0,0 +1,31 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector;
+
+import io.netty.buffer.ArrowBuf;
+
+/**
+ * Content is backed by a buffer and can be loaded/unloaded
+ */
+public interface BufferBacked {
+
+  void load(ArrowBuf data);
+
+  ArrowBuf unLoad();
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/FieldVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/FieldVector.java b/java/vector/src/main/java/org/apache/arrow/vector/FieldVector.java
new file mode 100644
index 0000000..b28433c
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/FieldVector.java
@@ -0,0 +1,65 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector;
+
+import java.util.List;
+
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+import org.apache.arrow.vector.types.pojo.Field;
+
+import io.netty.buffer.ArrowBuf;
+
+/**
+ * A vector corresponding to a Field in the schema
+ * It has inner vectors backed by buffers (validity, offsets, data, ...)
+ */
+public interface FieldVector extends ValueVector {
+
+  /**
+   * Initializes the child vectors
+   * to be later loaded with loadBuffers
+   * @param children the schema
+   */
+  void initializeChildrenFromFields(List<Field> children);
+
+  /**
+   * the returned list is the same size as the list passed to initializeChildrenFromFields
+   * @return the children according to schema (empty for primitive types)
+   */
+  List<FieldVector> getChildrenFromFields();
+
+  /**
+   * loads data in the vectors
+   * (ownBuffers must be the same size as getFieldVectors())
+   * @param fieldNode the fieldNode
+   * @param ownBuffers the buffers for this Field (own buffers only, children not included)
+   */
+  void loadFieldBuffers(ArrowFieldNode fieldNode, List<ArrowBuf> ownBuffers);
+
+  /**
+   * (same size as getFieldVectors() since it is their content)
+   * @return the buffers containing the data for this vector (ready for reading)
+   */
+  List<ArrowBuf> getFieldBuffers();
+
+  /**
+   * @return the inner vectors for this field as defined by the TypeLayout
+   */
+  List<BufferBacked> getFieldInnerVectors();
+
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/ValueVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/ValueVector.java b/java/vector/src/main/java/org/apache/arrow/vector/ValueVector.java
index 35321c9..ba7790e 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/ValueVector.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/ValueVector.java
@@ -19,14 +19,14 @@ package org.apache.arrow.vector;
 
 import java.io.Closeable;
 
-import io.netty.buffer.ArrowBuf;
-
 import org.apache.arrow.memory.BufferAllocator;
 import org.apache.arrow.memory.OutOfMemoryException;
 import org.apache.arrow.vector.complex.reader.FieldReader;
 import org.apache.arrow.vector.types.Types.MinorType;
-import org.apache.arrow.vector.util.TransferPair;
 import org.apache.arrow.vector.types.pojo.Field;
+import org.apache.arrow.vector.util.TransferPair;
+
+import io.netty.buffer.ArrowBuf;
 
 /**
  * An abstraction that is used to store a sequence of values in an individual column.

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/VectorLoader.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/VectorLoader.java b/java/vector/src/main/java/org/apache/arrow/vector/VectorLoader.java
new file mode 100644
index 0000000..58ac68b
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/VectorLoader.java
@@ -0,0 +1,99 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+import org.apache.arrow.vector.schema.ArrowRecordBatch;
+import org.apache.arrow.vector.schema.VectorLayout;
+import org.apache.arrow.vector.types.pojo.Field;
+import org.apache.arrow.vector.types.pojo.Schema;
+
+import com.google.common.collect.Iterators;
+
+import io.netty.buffer.ArrowBuf;
+
+/**
+ * Loads buffers into vectors
+ */
+public class VectorLoader {
+  private final List<FieldVector> fieldVectors;
+  private final List<Field> fields;
+
+  /**
+   * will create children in root based on schema
+   * @param schema the expected schema
+   * @param root the root to add vectors to based on schema
+   */
+  public VectorLoader(Schema schema, FieldVector root) {
+    super();
+    this.fields = schema.getFields();
+    root.initializeChildrenFromFields(fields);
+    this.fieldVectors = root.getChildrenFromFields();
+    if (this.fieldVectors.size() != fields.size()) {
+      throw new IllegalArgumentException("The root vector did not create the right number of children. found " + fieldVectors.size() + " expected " + fields.size());
+    }
+  }
+
+  /**
+   * Loads the record batch in the vectors
+   * will not close the record batch
+   * @param recordBatch
+   */
+  public void load(ArrowRecordBatch recordBatch) {
+    Iterator<ArrowBuf> buffers = recordBatch.getBuffers().iterator();
+    Iterator<ArrowFieldNode> nodes = recordBatch.getNodes().iterator();
+    for (int i = 0; i < fields.size(); ++i) {
+      Field field = fields.get(i);
+      FieldVector fieldVector = fieldVectors.get(i);
+      loadBuffers(fieldVector, field, buffers, nodes);
+    }
+    if (nodes.hasNext() || buffers.hasNext()) {
+      throw new IllegalArgumentException("not all nodes and buffers where consumed. nodes: " + Iterators.toString(nodes) + " buffers: " + Iterators.toString(buffers));
+    }
+  }
+
+  private void loadBuffers(FieldVector vector, Field field, Iterator<ArrowBuf> buffers, Iterator<ArrowFieldNode> nodes) {
+    ArrowFieldNode fieldNode = nodes.next();
+    List<VectorLayout> typeLayout = field.getTypeLayout().getVectors();
+    List<ArrowBuf> ownBuffers = new ArrayList<>(typeLayout.size());
+    for (int j = 0; j < typeLayout.size(); j++) {
+      ownBuffers.add(buffers.next());
+    }
+    try {
+      vector.loadFieldBuffers(fieldNode, ownBuffers);
+    } catch (RuntimeException e) {
+      throw new IllegalArgumentException("Could not load buffers for field " + field);
+    }
+    List<Field> children = field.getChildren();
+    if (children.size() > 0) {
+      List<FieldVector> childrenFromFields = vector.getChildrenFromFields();
+      checkArgument(children.size() == childrenFromFields.size(), "should have as many children as in the schema: found " + childrenFromFields.size() + " expected " + children.size());
+      for (int i = 0; i < childrenFromFields.size(); i++) {
+        Field child = children.get(i);
+        FieldVector fieldVector = childrenFromFields.get(i);
+        loadBuffers(fieldVector, child, buffers, nodes);
+      }
+    }
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/VectorUnloader.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/VectorUnloader.java b/java/vector/src/main/java/org/apache/arrow/vector/VectorUnloader.java
new file mode 100644
index 0000000..e4d37bf
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/VectorUnloader.java
@@ -0,0 +1,78 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.arrow.vector.ValueVector.Accessor;
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+import org.apache.arrow.vector.schema.ArrowRecordBatch;
+import org.apache.arrow.vector.schema.ArrowVectorType;
+import org.apache.arrow.vector.types.pojo.Schema;
+
+import io.netty.buffer.ArrowBuf;
+
+public class VectorUnloader {
+
+  private final Schema schema;
+  private final int valueCount;
+  private final List<FieldVector> vectors;
+
+  public VectorUnloader(FieldVector parent) {
+    super();
+    this.schema = new Schema(parent.getField().getChildren());
+    this.valueCount = parent.getAccessor().getValueCount();
+    this.vectors = parent.getChildrenFromFields();
+  }
+
+  public Schema getSchema() {
+    return schema;
+  }
+
+  public ArrowRecordBatch getRecordBatch() {
+    List<ArrowFieldNode> nodes = new ArrayList<>();
+    List<ArrowBuf> buffers = new ArrayList<>();
+    for (FieldVector vector : vectors) {
+      appendNodes(vector, nodes, buffers);
+    }
+    return new ArrowRecordBatch(valueCount, nodes, buffers);
+  }
+
+  private void appendNodes(FieldVector vector, List<ArrowFieldNode> nodes, List<ArrowBuf> buffers) {
+    Accessor accessor = vector.getAccessor();
+    int nullCount = 0;
+    // TODO: should not have to do that
+    // we can do that a lot more efficiently (for example with Long.bitCount(i))
+    for (int i = 0; i < accessor.getValueCount(); i++) {
+      if (accessor.isNull(i)) {
+        nullCount ++;
+      }
+    }
+    nodes.add(new ArrowFieldNode(accessor.getValueCount(), nullCount));
+    List<ArrowBuf> fieldBuffers = vector.getFieldBuffers();
+    List<ArrowVectorType> expectedBuffers = vector.getField().getTypeLayout().getVectorTypes();
+    if (fieldBuffers.size() != expectedBuffers.size()) {
+      throw new IllegalArgumentException("wrong number of buffers for field " + vector.getField() + ". found: " + fieldBuffers);
+    }
+    buffers.addAll(fieldBuffers);
+    for (FieldVector child : vector.getChildrenFromFields()) {
+      appendNodes(child, nodes, buffers);
+    }
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/ZeroVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/ZeroVector.java b/java/vector/src/main/java/org/apache/arrow/vector/ZeroVector.java
index 705a24b..c2482ad 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/ZeroVector.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/ZeroVector.java
@@ -17,25 +17,23 @@
  */
 package org.apache.arrow.vector;
 
-import com.google.flatbuffers.FlatBufferBuilder;
-import io.netty.buffer.ArrowBuf;
-
 import java.util.Collections;
 import java.util.Iterator;
+import java.util.List;
 
-import org.apache.arrow.flatbuf.Type;
 import org.apache.arrow.memory.BufferAllocator;
 import org.apache.arrow.memory.OutOfMemoryException;
 import org.apache.arrow.vector.complex.impl.NullReader;
 import org.apache.arrow.vector.complex.reader.FieldReader;
+import org.apache.arrow.vector.schema.ArrowFieldNode;
 import org.apache.arrow.vector.types.Types.MinorType;
 import org.apache.arrow.vector.types.pojo.ArrowType.Null;
 import org.apache.arrow.vector.types.pojo.Field;
 import org.apache.arrow.vector.util.TransferPair;
 
-import com.google.common.collect.Iterators;
+import io.netty.buffer.ArrowBuf;
 
-public class ZeroVector implements ValueVector {
+public class ZeroVector implements FieldVector {
   public final static ZeroVector INSTANCE = new ZeroVector();
 
   private final String name = "[DEFAULT]";
@@ -175,4 +173,33 @@ public class ZeroVector implements ValueVector {
   public FieldReader getReader() {
     return NullReader.INSTANCE;
   }
+
+  @Override
+  public void initializeChildrenFromFields(List<Field> children) {
+    if (!children.isEmpty()) {
+      throw new IllegalArgumentException("Zero vector has no children");
+    }
+  }
+
+  @Override
+  public List<FieldVector> getChildrenFromFields() {
+    return Collections.emptyList();
+  }
+
+  @Override
+  public void loadFieldBuffers(ArrowFieldNode fieldNode, List<ArrowBuf> ownBuffers) {
+    if (!ownBuffers.isEmpty()) {
+      throw new IllegalArgumentException("Zero vector has no buffers");
+    }
+  }
+
+  @Override
+  public List<ArrowBuf> getFieldBuffers() {
+    return Collections.emptyList();
+  }
+
+  @Override
+  public List<BufferBacked> getFieldInnerVectors() {
+    return Collections.emptyList();
+  }
 }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractContainerVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractContainerVector.java b/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractContainerVector.java
index ed77975..2f68886 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractContainerVector.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractContainerVector.java
@@ -17,22 +17,13 @@
  */
 package org.apache.arrow.vector.complex;
 
-import java.util.Collection;
-
-import javax.annotation.Nullable;
-
-import org.apache.arrow.flatbuf.Field;
 import org.apache.arrow.memory.BufferAllocator;
 import org.apache.arrow.memory.OutOfMemoryException;
+import org.apache.arrow.vector.FieldVector;
 import org.apache.arrow.vector.ValueVector;
 import org.apache.arrow.vector.types.Types.MinorType;
 import org.apache.arrow.vector.util.CallBack;
 
-import com.google.common.base.Function;
-import com.google.common.base.Preconditions;
-import com.google.common.collect.Iterables;
-import com.google.common.collect.Sets;
-
 /**
  * Base class for composite vectors.
  *
@@ -65,8 +56,8 @@ public abstract class AbstractContainerVector implements ValueVector {
   /**
    * Returns a {@link org.apache.arrow.vector.ValueVector} corresponding to the given field name if exists or null.
    */
-  public ValueVector getChild(String name) {
-    return getChild(name, ValueVector.class);
+  public FieldVector getChild(String name) {
+    return getChild(name, FieldVector.class);
   }
 
   /**
@@ -81,7 +72,7 @@ public abstract class AbstractContainerVector implements ValueVector {
 
   protected <T extends ValueVector> T typeify(ValueVector v, Class<T> clazz) {
     if (clazz.isAssignableFrom(v.getClass())) {
-      return (T) v;
+      return clazz.cast(v);
     }
     throw new IllegalStateException(String.format("Vector requested [%s] was different than type stored [%s]. Arrow doesn't yet support hetergenous types.", clazz.getSimpleName(), v.getClass().getSimpleName()));
   }
@@ -94,10 +85,10 @@ public abstract class AbstractContainerVector implements ValueVector {
   public abstract int size();
 
   // add a new vector with the input MajorType or return the existing vector if we already added one with the same type
-  public abstract <T extends ValueVector> T addOrGet(String name, MinorType minorType, Class<T> clazz, int... precisionScale);
+  public abstract <T extends FieldVector> T addOrGet(String name, MinorType minorType, Class<T> clazz, int... precisionScale);
 
   // return the child vector with the input name
-  public abstract <T extends ValueVector> T getChild(String name, Class<T> clazz);
+  public abstract <T extends FieldVector> T getChild(String name, Class<T> clazz);
 
   // return the child vector's ordinal in the composite container
   public abstract VectorWithOrdinal getChildVectorWithOrdinal(String name);

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractMapVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractMapVector.java b/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractMapVector.java
index 5964f80..23b4997 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractMapVector.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/complex/AbstractMapVector.java
@@ -17,23 +17,24 @@
  */
 package org.apache.arrow.vector.complex;
 
-import com.google.common.collect.ImmutableList;
-import io.netty.buffer.ArrowBuf;
-
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
-import org.apache.arrow.flatbuf.Field;
 import org.apache.arrow.memory.BufferAllocator;
+import org.apache.arrow.vector.FieldVector;
 import org.apache.arrow.vector.ValueVector;
 import org.apache.arrow.vector.types.Types.MinorType;
 import org.apache.arrow.vector.util.CallBack;
 import org.apache.arrow.vector.util.MapWithOrdinal;
 
 import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 
+import io.netty.buffer.ArrowBuf;
+
 /*
  * Base class for MapVectors. Currently used by RepeatedMapVector and MapVector
  */
@@ -41,7 +42,7 @@ public abstract class AbstractMapVector extends AbstractContainerVector {
   private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(AbstractContainerVector.class);
 
   // Maintains a map with key as field name and value is the vector itself
-  private final MapWithOrdinal<String, ValueVector> vectors =  new MapWithOrdinal<>();
+  private final MapWithOrdinal<String, FieldVector> vectors =  new MapWithOrdinal<>();
 
   protected AbstractMapVector(String name, BufferAllocator allocator, CallBack callBack) {
     super(name, allocator, callBack);
@@ -109,19 +110,19 @@ public abstract class AbstractMapVector extends AbstractContainerVector {
    * @return resultant {@link org.apache.arrow.vector.ValueVector}
    */
   @Override
-  public <T extends ValueVector> T addOrGet(String name, MinorType minorType, Class<T> clazz, int... precisionScale) {
+  public <T extends FieldVector> T addOrGet(String name, MinorType minorType, Class<T> clazz, int... precisionScale) {
     final ValueVector existing = getChild(name);
     boolean create = false;
     if (existing == null) {
       create = true;
     } else if (clazz.isAssignableFrom(existing.getClass())) {
-      return (T) existing;
+      return clazz.cast(existing);
     } else if (nullFilled(existing)) {
       existing.clear();
       create = true;
     }
     if (create) {
-      final T vector = (T) minorType.getNewVector(name, allocator, callBack, precisionScale);
+      final T vector = clazz.cast(minorType.getNewVector(name, allocator, callBack, precisionScale));
       putChild(name, vector);
       if (callBack!=null) {
         callBack.doWork();
@@ -153,7 +154,7 @@ public abstract class AbstractMapVector extends AbstractContainerVector {
    * field name if exists or null.
    */
   @Override
-  public <T extends ValueVector> T getChild(String name, Class<T> clazz) {
+  public <T extends FieldVector> T getChild(String name, Class<T> clazz) {
     final ValueVector v = vectors.get(name.toLowerCase());
     if (v == null) {
       return null;
@@ -161,12 +162,25 @@ public abstract class AbstractMapVector extends AbstractContainerVector {
     return typeify(v, clazz);
   }
 
+  protected ValueVector add(String name, MinorType minorType, int... precisionScale) {
+    final ValueVector existing = getChild(name);
+    if (existing != null) {
+      throw new IllegalStateException(String.format("Vector already exists: Existing[%s], Requested[%s] ", existing.getClass().getSimpleName(), minorType));
+    }
+    FieldVector vector = minorType.getNewVector(name, allocator, callBack, precisionScale);
+    putChild(name, vector);
+    if (callBack!=null) {
+      callBack.doWork();
+    }
+    return vector;
+  }
+
   /**
    * Inserts the vector with the given name if it does not exist else replaces it with the new value.
    *
    * Note that this method does not enforce any vector type check nor throws a schema change exception.
    */
-  protected void putChild(String name, ValueVector vector) {
+  protected void putChild(String name, FieldVector vector) {
     putVector(name, vector);
   }
 
@@ -175,7 +189,7 @@ public abstract class AbstractMapVector extends AbstractContainerVector {
    * @param name  field name
    * @param vector  vector to be inserted
    */
-  protected void putVector(String name, ValueVector vector) {
+  protected void putVector(String name, FieldVector vector) {
     final ValueVector old = vectors.put(
         Preconditions.checkNotNull(name, "field name cannot be null").toLowerCase(),
         Preconditions.checkNotNull(vector, "vector cannot be null")
@@ -189,9 +203,9 @@ public abstract class AbstractMapVector extends AbstractContainerVector {
   /**
    * Returns a sequence of underlying child vectors.
    */
-  protected List<ValueVector> getChildren() {
+  protected List<FieldVector> getChildren() {
     int size = vectors.size();
-    List<ValueVector> children = new ArrayList<>();
+    List<FieldVector> children = new ArrayList<>();
     for (int i = 0; i < size; i++) {
       children.add(vectors.getByOrdinal(i));
     }
@@ -216,7 +230,7 @@ public abstract class AbstractMapVector extends AbstractContainerVector {
 
   @Override
   public Iterator<ValueVector> iterator() {
-    return vectors.values().iterator();
+    return Collections.<ValueVector>unmodifiableCollection(vectors.values()).iterator();
   }
 
   /**

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/complex/BaseRepeatedValueVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/complex/BaseRepeatedValueVector.java b/java/vector/src/main/java/org/apache/arrow/vector/complex/BaseRepeatedValueVector.java
index 4226274..517d20c 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/complex/BaseRepeatedValueVector.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/complex/BaseRepeatedValueVector.java
@@ -17,8 +17,6 @@
  */
 package org.apache.arrow.vector.complex;
 
-import io.netty.buffer.ArrowBuf;
-
 import java.util.Collections;
 import java.util.Iterator;
 
@@ -26,29 +24,32 @@ import org.apache.arrow.flatbuf.Type;
 import org.apache.arrow.memory.BufferAllocator;
 import org.apache.arrow.vector.AddOrGetResult;
 import org.apache.arrow.vector.BaseValueVector;
+import org.apache.arrow.vector.FieldVector;
 import org.apache.arrow.vector.UInt4Vector;
 import org.apache.arrow.vector.ValueVector;
 import org.apache.arrow.vector.ZeroVector;
+import org.apache.arrow.vector.types.Types.MinorType;
+import org.apache.arrow.vector.util.SchemaChangeRuntimeException;
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ObjectArrays;
-import org.apache.arrow.vector.types.Types.MinorType;
-import org.apache.arrow.vector.util.SchemaChangeRuntimeException;
+
+import io.netty.buffer.ArrowBuf;
 
 public abstract class BaseRepeatedValueVector extends BaseValueVector implements RepeatedValueVector {
 
-  public final static ValueVector DEFAULT_DATA_VECTOR = ZeroVector.INSTANCE;
+  public final static FieldVector DEFAULT_DATA_VECTOR = ZeroVector.INSTANCE;
   public final static String OFFSETS_VECTOR_NAME = "$offsets$";
   public final static String DATA_VECTOR_NAME = "$data$";
 
   protected final UInt4Vector offsets;
-  protected ValueVector vector;
+  protected FieldVector vector;
 
   protected BaseRepeatedValueVector(String name, BufferAllocator allocator) {
     this(name, allocator, DEFAULT_DATA_VECTOR);
   }
 
-  protected BaseRepeatedValueVector(String name, BufferAllocator allocator, ValueVector vector) {
+  protected BaseRepeatedValueVector(String name, BufferAllocator allocator, FieldVector vector) {
     super(name, allocator);
     this.offsets = new UInt4Vector(OFFSETS_VECTOR_NAME, allocator);
     this.vector = Preconditions.checkNotNull(vector, "data vector cannot be null");
@@ -83,7 +84,7 @@ public abstract class BaseRepeatedValueVector extends BaseValueVector implements
   }
 
   @Override
-  public ValueVector getDataVector() {
+  public FieldVector getDataVector() {
     return vector;
   }
 
@@ -121,7 +122,7 @@ public abstract class BaseRepeatedValueVector extends BaseValueVector implements
 
   @Override
   public Iterator<ValueVector> iterator() {
-    return Collections.singleton(getDataVector()).iterator();
+    return Collections.<ValueVector>singleton(getDataVector()).iterator();
   }
 
   @Override
@@ -167,7 +168,7 @@ public abstract class BaseRepeatedValueVector extends BaseValueVector implements
     return new AddOrGetResult<>((T)vector, created);
   }
 
-  protected void replaceDataVector(ValueVector v) {
+  protected void replaceDataVector(FieldVector v) {
     vector.clear();
     vector = v;
   }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/complex/ListVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/complex/ListVector.java b/java/vector/src/main/java/org/apache/arrow/vector/complex/ListVector.java
index c6c6b09..2984c36 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/complex/ListVector.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/complex/ListVector.java
@@ -18,15 +18,18 @@
  ******************************************************************************/
 package org.apache.arrow.vector.complex;
 
-import com.google.common.collect.ImmutableList;
-import com.google.flatbuffers.FlatBufferBuilder;
-import io.netty.buffer.ArrowBuf;
+import static java.util.Collections.singletonList;
 
+import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 
 import org.apache.arrow.memory.BufferAllocator;
 import org.apache.arrow.memory.OutOfMemoryException;
 import org.apache.arrow.vector.AddOrGetResult;
+import org.apache.arrow.vector.BaseDataValueVector;
+import org.apache.arrow.vector.BufferBacked;
+import org.apache.arrow.vector.FieldVector;
 import org.apache.arrow.vector.UInt1Vector;
 import org.apache.arrow.vector.UInt4Vector;
 import org.apache.arrow.vector.ValueVector;
@@ -36,18 +39,24 @@ import org.apache.arrow.vector.complex.impl.UnionListReader;
 import org.apache.arrow.vector.complex.impl.UnionListWriter;
 import org.apache.arrow.vector.complex.reader.FieldReader;
 import org.apache.arrow.vector.complex.writer.FieldWriter;
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+import org.apache.arrow.vector.types.Types;
 import org.apache.arrow.vector.types.Types.MinorType;
 import org.apache.arrow.vector.types.pojo.Field;
 import org.apache.arrow.vector.util.CallBack;
 import org.apache.arrow.vector.util.JsonStringArrayList;
 import org.apache.arrow.vector.util.TransferPair;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ObjectArrays;
 
-public class ListVector extends BaseRepeatedValueVector {
+import io.netty.buffer.ArrowBuf;
+
+public class ListVector extends BaseRepeatedValueVector implements FieldVector {
 
-  UInt4Vector offsets;
+  final UInt4Vector offsets;
   final UInt1Vector bits;
+  private final List<BufferBacked> innerVectors;
   private Mutator mutator = new Mutator();
   private Accessor accessor = new Accessor();
   private UnionListWriter writer;
@@ -57,12 +66,46 @@ public class ListVector extends BaseRepeatedValueVector {
   public ListVector(String name, BufferAllocator allocator, CallBack callBack) {
     super(name, allocator);
     this.bits = new UInt1Vector("$bits$", allocator);
-    offsets = getOffsetVector();
+    this.offsets = getOffsetVector();
+    this.innerVectors = Collections.unmodifiableList(Arrays.<BufferBacked>asList(bits, offsets));
     this.writer = new UnionListWriter(this);
     this.reader = new UnionListReader(this);
     this.callBack = callBack;
   }
 
+  @Override
+  public void initializeChildrenFromFields(List<Field> children) {
+    if (children.size() != 1) {
+      throw new IllegalArgumentException("Lists have only one child. Found: " + children);
+    }
+    Field field = children.get(0);
+    MinorType minorType = Types.getMinorTypeForArrowType(field.getType());
+    AddOrGetResult<FieldVector> addOrGetVector = addOrGetVector(minorType);
+    if (!addOrGetVector.isCreated()) {
+      throw new IllegalArgumentException("Child vector already existed: " + addOrGetVector.getVector());
+    }
+  }
+
+  @Override
+  public List<FieldVector> getChildrenFromFields() {
+    return singletonList(getDataVector());
+  }
+
+  @Override
+  public void loadFieldBuffers(ArrowFieldNode fieldNode, List<ArrowBuf> ownBuffers) {
+    BaseDataValueVector.load(getFieldInnerVectors(), ownBuffers);
+  }
+
+  @Override
+  public List<ArrowBuf> getFieldBuffers() {
+    return BaseDataValueVector.unload(getFieldInnerVectors());
+  }
+
+  @Override
+  public List<BufferBacked> getFieldInnerVectors() {
+    return innerVectors;
+  }
+
   public UnionListWriter getWriter() {
     return writer;
   }
@@ -86,7 +129,7 @@ public class ListVector extends BaseRepeatedValueVector {
   }
 
   @Override
-  public ValueVector getDataVector() {
+  public FieldVector getDataVector() {
     return vector;
   }
 
@@ -298,4 +341,5 @@ public class ListVector extends BaseRepeatedValueVector {
       bits.getMutator().setValueCount(valueCount);
     }
   }
+
 }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/complex/MapVector.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/complex/MapVector.java b/java/vector/src/main/java/org/apache/arrow/vector/complex/MapVector.java
index 0cb613e..e369658 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/complex/MapVector.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/complex/MapVector.java
@@ -17,10 +17,10 @@
  */
 package org.apache.arrow.vector.complex;
 
-import io.netty.buffer.ArrowBuf;
-
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
@@ -28,13 +28,17 @@ import java.util.Map;
 import javax.annotation.Nullable;
 
 import org.apache.arrow.memory.BufferAllocator;
+import org.apache.arrow.vector.BaseDataValueVector;
 import org.apache.arrow.vector.BaseValueVector;
+import org.apache.arrow.vector.BufferBacked;
+import org.apache.arrow.vector.FieldVector;
 import org.apache.arrow.vector.ValueVector;
 import org.apache.arrow.vector.complex.impl.SingleMapReaderImpl;
 import org.apache.arrow.vector.complex.reader.FieldReader;
 import org.apache.arrow.vector.holders.ComplexHolder;
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+import org.apache.arrow.vector.types.Types;
 import org.apache.arrow.vector.types.Types.MinorType;
-import org.apache.arrow.vector.types.pojo.ArrowType;
 import org.apache.arrow.vector.types.pojo.ArrowType.Tuple;
 import org.apache.arrow.vector.types.pojo.Field;
 import org.apache.arrow.vector.util.CallBack;
@@ -45,7 +49,9 @@ import com.google.common.base.Preconditions;
 import com.google.common.collect.Ordering;
 import com.google.common.primitives.Ints;
 
-public class MapVector extends AbstractMapVector {
+import io.netty.buffer.ArrowBuf;
+
+public class MapVector extends AbstractMapVector implements FieldVector {
   //private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(MapVector.class);
 
   private final SingleMapReaderImpl reader = new SingleMapReaderImpl(MapVector.this);
@@ -53,6 +59,9 @@ public class MapVector extends AbstractMapVector {
   private final Mutator mutator = new Mutator();
   int valueCount;
 
+  // TODO: validity vector
+  private final List<BufferBacked> innerVectors = Collections.unmodifiableList(Arrays.<BufferBacked>asList());
+
   public MapVector(String name, BufferAllocator allocator, CallBack callBack){
     super(name, allocator, callBack);
   }
@@ -120,7 +129,7 @@ public class MapVector extends AbstractMapVector {
     int expectedSize = getBufferSize();
     int actualSize   = super.getBufferSize();
 
-    Preconditions.checkArgument(expectedSize == actualSize);
+    Preconditions.checkArgument(expectedSize == actualSize, expectedSize + " != " + actualSize);
     return super.getBuffers(clear);
   }
 
@@ -159,7 +168,7 @@ public class MapVector extends AbstractMapVector {
       this.to.ephPair = null;
 
       int i = 0;
-      ValueVector vector;
+      FieldVector vector;
       for (String child:from.getChildFieldNames()) {
         int preSize = to.size();
         vector = from.getChild(child);
@@ -175,7 +184,7 @@ public class MapVector extends AbstractMapVector {
         // (This is similar to what happens in ScanBatch where the children cannot be added till they are
         // read). To take care of this, we ensure that the hashCode of the MaterializedField does not
         // include the hashCode of the children but is based only on MaterializedField$key.
-        final ValueVector newVector = to.addOrGet(child, vector.getMinorType(), vector.getClass());
+        final FieldVector newVector = to.addOrGet(child, vector.getMinorType(), vector.getClass());
         if (allocate && to.size() != preSize) {
           newVector.allocateNew();
         }
@@ -315,13 +324,45 @@ public class MapVector extends AbstractMapVector {
 
   @Override
   public void close() {
-    final Collection<ValueVector> vectors = getChildren();
-    for (final ValueVector v : vectors) {
+    final Collection<FieldVector> vectors = getChildren();
+    for (final FieldVector v : vectors) {
       v.close();
     }
     vectors.clear();
+
     valueCount = 0;
 
     super.close();
  }
+
+  @Override
+  public void initializeChildrenFromFields(List<Field> children) {
+    for (Field field : children) {
+      MinorType minorType = Types.getMinorTypeForArrowType(field.getType());
+      FieldVector vector = (FieldVector)this.add(field.getName(), minorType);
+      vector.initializeChildrenFromFields(field.getChildren());
+    }
+  }
+
+  @Override
+  public List<FieldVector> getChildrenFromFields() {
+    return getChildren();
+  }
+
+  @Override
+  public void loadFieldBuffers(ArrowFieldNode fieldNode, List<ArrowBuf> ownBuffers) {
+    BaseDataValueVector.load(getFieldInnerVectors(), ownBuffers);
+    // TODO: something with fieldNode?
+  }
+
+  @Override
+  public List<ArrowBuf> getFieldBuffers() {
+    return BaseDataValueVector.unload(getFieldInnerVectors());
+  }
+
+  @Override
+  public List<BufferBacked> getFieldInnerVectors() {
+    return innerVectors;
+  }
+
 }

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/ComplexWriterImpl.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/ComplexWriterImpl.java b/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/ComplexWriterImpl.java
index 4d2adfb..89bfefc 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/ComplexWriterImpl.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/ComplexWriterImpl.java
@@ -22,9 +22,9 @@ import org.apache.arrow.vector.complex.MapVector;
 import org.apache.arrow.vector.complex.StateTool;
 import org.apache.arrow.vector.complex.writer.BaseWriter.ComplexWriter;
 import org.apache.arrow.vector.types.Types.MinorType;
+import org.apache.arrow.vector.types.pojo.Field;
 
 import com.google.common.base.Preconditions;
-import org.apache.arrow.vector.types.pojo.Field;
 
 public class ComplexWriterImpl extends AbstractFieldWriter implements ComplexWriter {
 //  private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(ComplexWriterImpl.class);

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/PromotableWriter.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/PromotableWriter.java b/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/PromotableWriter.java
index 586b128..c282688 100644
--- a/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/PromotableWriter.java
+++ b/java/vector/src/main/java/org/apache/arrow/vector/complex/impl/PromotableWriter.java
@@ -17,6 +17,7 @@
  */
 package org.apache.arrow.vector.complex.impl;
 
+import org.apache.arrow.vector.FieldVector;
 import org.apache.arrow.vector.ValueVector;
 import org.apache.arrow.vector.ZeroVector;
 import org.apache.arrow.vector.complex.AbstractMapVector;
@@ -129,7 +130,7 @@ public class PromotableWriter extends AbstractPromotableFieldWriter {
     } else if (listVector != null) {
       unionVector = listVector.promoteToUnion();
     }
-    unionVector.addVector(tp.getTo());
+    unionVector.addVector((FieldVector)tp.getTo());
     writer = new UnionWriter(unionVector);
     writer.setPosition(idx());
     for (int i = 0; i < idx(); i++) {

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowBlock.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowBlock.java b/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowBlock.java
new file mode 100644
index 0000000..90fb02b
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowBlock.java
@@ -0,0 +1,82 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+import org.apache.arrow.flatbuf.Block;
+import org.apache.arrow.vector.schema.FBSerializable;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+public class ArrowBlock implements FBSerializable {
+
+  private final long offset;
+  private final int metadataLength;
+  private final long bodyLength;
+
+  public ArrowBlock(long offset, int metadataLength, long bodyLength) {
+    super();
+    this.offset = offset;
+    this.metadataLength = metadataLength;
+    this.bodyLength = bodyLength;
+  }
+
+  public long getOffset() {
+    return offset;
+  }
+
+  public int getMetadataLength() {
+    return metadataLength;
+  }
+
+  public long getBodyLength() {
+    return bodyLength;
+  }
+
+  @Override
+  public int writeTo(FlatBufferBuilder builder) {
+    return Block.createBlock(builder, offset, metadataLength, bodyLength);
+  }
+
+  @Override
+  public int hashCode() {
+    final int prime = 31;
+    int result = 1;
+    result = prime * result + (int) (bodyLength ^ (bodyLength >>> 32));
+    result = prime * result + metadataLength;
+    result = prime * result + (int) (offset ^ (offset >>> 32));
+    return result;
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (this == obj)
+      return true;
+    if (obj == null)
+      return false;
+    if (getClass() != obj.getClass())
+      return false;
+    ArrowBlock other = (ArrowBlock) obj;
+    if (bodyLength != other.bodyLength)
+      return false;
+    if (metadataLength != other.metadataLength)
+      return false;
+    if (offset != other.offset)
+      return false;
+    return true;
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowFooter.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowFooter.java b/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowFooter.java
new file mode 100644
index 0000000..01e175b
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowFooter.java
@@ -0,0 +1,144 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.arrow.flatbuf.Block;
+import org.apache.arrow.flatbuf.Footer;
+import org.apache.arrow.vector.schema.FBSerializable;
+import org.apache.arrow.vector.types.pojo.Schema;
+
+import com.google.flatbuffers.FlatBufferBuilder;
+
+public class ArrowFooter implements FBSerializable {
+
+  private final Schema schema;
+
+  private final List<ArrowBlock> dictionaries;
+
+  private final List<ArrowBlock> recordBatches;
+
+  public ArrowFooter(Schema schema, List<ArrowBlock> dictionaries, List<ArrowBlock> recordBatches) {
+    super();
+    this.schema = schema;
+    this.dictionaries = dictionaries;
+    this.recordBatches = recordBatches;
+  }
+
+  public ArrowFooter(Footer footer) {
+    this(
+        Schema.convertSchema(footer.schema()),
+        dictionaries(footer),
+        recordBatches(footer)
+        );
+  }
+
+  private static List<ArrowBlock> recordBatches(Footer footer) {
+    List<ArrowBlock> recordBatches = new ArrayList<>();
+    Block tempBLock = new Block();
+    int recordBatchesLength = footer.recordBatchesLength();
+    for (int i = 0; i < recordBatchesLength; i++) {
+      Block block = footer.recordBatches(tempBLock, i);
+      recordBatches.add(new ArrowBlock(block.offset(), block.metaDataLength(), block.bodyLength()));
+    }
+    return recordBatches;
+  }
+
+  private static List<ArrowBlock> dictionaries(Footer footer) {
+    List<ArrowBlock> dictionaries = new ArrayList<>();
+    Block tempBLock = new Block();
+    int dictionariesLength = footer.dictionariesLength();
+    for (int i = 0; i < dictionariesLength; i++) {
+      Block block = footer.dictionaries(tempBLock, i);
+      dictionaries.add(new ArrowBlock(block.offset(), block.metaDataLength(), block.bodyLength()));
+    }
+    return dictionaries;
+  }
+
+  public Schema getSchema() {
+    return schema;
+  }
+
+  public List<ArrowBlock> getDictionaries() {
+    return dictionaries;
+  }
+
+  public List<ArrowBlock> getRecordBatches() {
+    return recordBatches;
+  }
+
+  @Override
+  public int writeTo(FlatBufferBuilder builder) {
+    int schemaIndex = schema.getSchema(builder);
+    Footer.startDictionariesVector(builder, dictionaries.size());
+    int dicsOffset = endVector(builder, dictionaries);
+    Footer.startRecordBatchesVector(builder, recordBatches.size());
+    int rbsOffset = endVector(builder, recordBatches);
+    Footer.startFooter(builder);
+    Footer.addSchema(builder, schemaIndex);
+    Footer.addDictionaries(builder, dicsOffset);
+    Footer.addRecordBatches(builder, rbsOffset);
+    return Footer.endFooter(builder);
+  }
+
+  private int endVector(FlatBufferBuilder builder, List<ArrowBlock> blocks) {
+    for (ArrowBlock block : blocks) {
+      block.writeTo(builder);
+    }
+    return builder.endVector();
+  }
+
+  @Override
+  public int hashCode() {
+    final int prime = 31;
+    int result = 1;
+    result = prime * result + ((dictionaries == null) ? 0 : dictionaries.hashCode());
+    result = prime * result + ((recordBatches == null) ? 0 : recordBatches.hashCode());
+    result = prime * result + ((schema == null) ? 0 : schema.hashCode());
+    return result;
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (this == obj)
+      return true;
+    if (obj == null)
+      return false;
+    if (getClass() != obj.getClass())
+      return false;
+    ArrowFooter other = (ArrowFooter) obj;
+    if (dictionaries == null) {
+      if (other.dictionaries != null)
+        return false;
+    } else if (!dictionaries.equals(other.dictionaries))
+      return false;
+    if (recordBatches == null) {
+      if (other.recordBatches != null)
+        return false;
+    } else if (!recordBatches.equals(other.recordBatches))
+      return false;
+    if (schema == null) {
+      if (other.schema != null)
+        return false;
+    } else if (!schema.equals(other.schema))
+      return false;
+    return true;
+  }
+}

http://git-wip-us.apache.org/repos/asf/arrow/blob/803afeb5/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowReader.java
----------------------------------------------------------------------
diff --git a/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowReader.java b/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowReader.java
new file mode 100644
index 0000000..bbcd3e9
--- /dev/null
+++ b/java/vector/src/main/java/org/apache/arrow/vector/file/ArrowReader.java
@@ -0,0 +1,151 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.arrow.vector.file;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.SeekableByteChannel;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.apache.arrow.flatbuf.Buffer;
+import org.apache.arrow.flatbuf.FieldNode;
+import org.apache.arrow.flatbuf.Footer;
+import org.apache.arrow.flatbuf.RecordBatch;
+import org.apache.arrow.memory.BufferAllocator;
+import org.apache.arrow.vector.schema.ArrowFieldNode;
+import org.apache.arrow.vector.schema.ArrowRecordBatch;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import io.netty.buffer.ArrowBuf;
+
+public class ArrowReader implements AutoCloseable {
+  private static final Logger LOGGER = LoggerFactory.getLogger(ArrowReader.class);
+
+  private static final byte[] MAGIC = "ARROW1".getBytes();
+
+  private final SeekableByteChannel in;
+
+  private final BufferAllocator allocator;
+
+  private ArrowFooter footer;
+
+  public ArrowReader(SeekableByteChannel in, BufferAllocator allocator) {
+    super();
+    this.in = in;
+    this.allocator = allocator;
+  }
+
+  private int readFully(ArrowBuf buffer, int l) throws IOException {
+    int n = readFully(buffer.nioBuffer(buffer.writerIndex(), l));
+    buffer.writerIndex(n);
+    if (n != l) {
+      throw new IllegalStateException(n + " != " + l);
+    }
+    return n;
+  }
+
+  private int readFully(ByteBuffer buffer) throws IOException {
+    int total = 0;
+    int n;
+    do {
+      n = in.read(buffer);
+      total += n;
+    } while (n >= 0 && buffer.remaining() > 0);
+    buffer.flip();
+    return total;
+  }
+
+  private static int bytesToInt(byte[] bytes) {
+    return ((int)(bytes[3] & 255) << 24) +
+           ((int)(bytes[2] & 255) << 16) +
+           ((int)(bytes[1] & 255) <<  8) +
+           ((int)(bytes[0] & 255) <<  0);
+  }
+
+  public ArrowFooter readFooter() throws IOException {
+    if (footer == null) {
+      if (in.size() <= (MAGIC.length * 2 + 4)) {
+        throw new InvalidArrowFileException("file too small: " + in.size());
+      }
+      ByteBuffer buffer = ByteBuffer.allocate(4 + MAGIC.length);
+      long footerLengthOffset = in.size() - buffer.remaining();
+      in.position(footerLengthOffset);
+      readFully(buffer);
+      byte[] array = buffer.array();
+      if (!Arrays.equals(MAGIC, Arrays.copyOfRange(array, 4, array.length))) {
+        throw new InvalidArrowFileException("missing Magic number " + Arrays.toString(buffer.array()));
+      }
+      int footerLength = bytesToInt(array);
+      if (footerLength <= 0 || footerLength + MAGIC.length * 2 + 4 > in.size()) {
+        throw new InvalidArrowFileException("invalid footer length: " + footerLength);
+      }
+      long footerOffset = footerLengthOffset - footerLength;
+      LOGGER.debug(String.format("Footer starts at %d, length: %d", footerOffset, footerLength));
+      ByteBuffer footerBuffer = ByteBuffer.allocate(footerLength);
+      in.position(footerOffset);
+      readFully(footerBuffer);
+      Footer footerFB = Footer.getRootAsFooter(footerBuffer);
+      this.footer = new ArrowFooter(footerFB);
+    }
+    return footer;
+  }
+
+  // TODO: read dictionaries
+
+  public ArrowRecordBatch readRecordBatch(ArrowBlock recordBatchBlock) throws IOException {
+    LOGGER.debug(String.format("RecordBatch at %d, metadata: %d, body: %d", recordBatchBlock.getOffset(), recordBatchBlock.getMetadataLength(), recordBatchBlock.getBodyLength()));
+    int l = (int)(recordBatchBlock.getMetadataLength() + recordBatchBlock.getBodyLength());
+    if (l < 0) {
+      throw new InvalidArrowFileException("block invalid: " + recordBatchBlock);
+    }
+    final ArrowBuf buffer = allocator.buffer(l);
+    LOGGER.debug("allocated buffer " + buffer);
+    in.position(recordBatchBlock.getOffset());
+    int n = readFully(buffer, l);
+    if (n != l) {
+      throw new IllegalStateException(n + " != " + l);
+    }
+    RecordBatch recordBatchFB = RecordBatch.getRootAsRecordBatch(buffer.nioBuffer().asReadOnlyBuffer());
+    int nodesLength = recordBatchFB.nodesLength();
+    final ArrowBuf body = buffer.slice(recordBatchBlock.getMetadataLength(), (int)recordBatchBlock.getBodyLength());
+    List<ArrowFieldNode> nodes = new ArrayList<>();
+    for (int i = 0; i < nodesLength; ++i) {
+      FieldNode node = recordBatchFB.nodes(i);
+      nodes.add(new ArrowFieldNode(node.length(), node.nullCount()));
+    }
+    List<ArrowBuf> buffers = new ArrayList<>();
+    for (int i = 0; i < recordBatchFB.buffersLength(); ++i) {
+      Buffer bufferFB = recordBatchFB.buffers(i);
+      LOGGER.debug(String.format("Buffer in RecordBatch at %d, length: %d", bufferFB.offset(), bufferFB.length()));
+      ArrowBuf vectorBuffer = body.slice((int)bufferFB.offset(), (int)bufferFB.length());
+      buffers.add(vectorBuffer);
+    }
+    ArrowRecordBatch arrowRecordBatch = new ArrowRecordBatch(recordBatchFB.length(), nodes, buffers);
+    LOGGER.debug("released buffer " + buffer);
+    buffer.release();
+    return arrowRecordBatch;
+  }
+
+  public void close() throws IOException {
+    in.close();
+  }
+
+}