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Posted to commits@metamodel.apache.org by ka...@apache.org on 2016/05/16 03:54:16 UTC

[41/42] metamodel git commit: Merge branch 'master' into 5.x

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/fixedwidth/src/main/java/org/apache/metamodel/fixedwidth/FixedWidthConfigurationReader.java
----------------------------------------------------------------------
diff --cc fixedwidth/src/main/java/org/apache/metamodel/fixedwidth/FixedWidthConfigurationReader.java
index 0000000,9154e5e..3c8d14c
mode 000000,100644..100644
--- a/fixedwidth/src/main/java/org/apache/metamodel/fixedwidth/FixedWidthConfigurationReader.java
+++ b/fixedwidth/src/main/java/org/apache/metamodel/fixedwidth/FixedWidthConfigurationReader.java
@@@ -1,0 -1,180 +1,180 @@@
 -/**
 - * 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.metamodel.fixedwidth;
 -
 -import java.io.BufferedReader;
 -import java.io.InputStream;
 -import java.io.InputStreamReader;
 -import java.util.ArrayList;
 -import java.util.HashMap;
 -import java.util.LinkedHashMap;
 -import java.util.List;
 -import java.util.Map;
 -import java.util.Map.Entry;
 -import java.util.regex.Matcher;
 -import java.util.regex.Pattern;
 -
 -import org.apache.metamodel.csv.CsvConfiguration;
 -import org.apache.metamodel.csv.CsvDataContext;
 -import org.apache.metamodel.data.DataSet;
 -import org.apache.metamodel.schema.Table;
 -import org.apache.metamodel.util.Action;
 -import org.apache.metamodel.util.Resource;
 -import org.slf4j.Logger;
 -import org.slf4j.LoggerFactory;
 -
 -/**
 - * Object capable of reading fixed width metadata from external sources and
 - * thereby producing an appropriate {@link FixedWidthConfiguration} to use with
 - * a {@link FixedWidthDataContext}.
 - */
 -public class FixedWidthConfigurationReader {
 -
 -    private static final Logger logger = LoggerFactory.getLogger(FixedWidthConfigurationReader.class);
 -
 -    // example: @1 COL1 $char1.
 -    private final Pattern PATTERN_SAS_INPUT_LINE = Pattern.compile("\\@(\\d+) (.+) .*?(\\d+)\\.");
 -
 -    // example: COL1 "Record type"
 -    private final Pattern PATTERN_SAS_LABEL_LINE = Pattern.compile("(.+) \\\"(.+)\\\"");
 -
 -    /**
 -     * Reads a {@link FixedWidthConfiguration} based on a SAS 'format file',
 -     * <a href=
 -     * "http://support.sas.com/documentation/cdl/en/etlug/67323/HTML/default/viewer.htm#p0h03yig7fp1qan1arghp3lwjqi6.htm">
 -     * described here</a>.
 -     * 
 -     * @param encoding
 -     * @param resource
 -     *            the format file resource
 -     * @param failOnInconsistentLineWidth
 -     * @return a {@link FixedWidthConfiguration} object to use
 -     */
 -    public FixedWidthConfiguration readFromSasFormatFile(String encoding, Resource resource,
 -            boolean failOnInconsistentLineWidth) {
 -        final List<FixedWidthColumnSpec> columnSpecs = new ArrayList<>();
 -
 -        final CsvDataContext dataContext = new CsvDataContext(resource, new CsvConfiguration());
 -        final Table table = dataContext.getDefaultSchema().getTable(0);
 -        try (final DataSet dataSet = dataContext.query().from(table).select("Name", "BeginPosition", "EndPosition")
 -                .execute()) {
 -            while (dataSet.next()) {
 -                final String name = (String) dataSet.getRow().getValue(0);
 -                final int beginPosition = Integer.parseInt((String) dataSet.getRow().getValue(1));
 -                final int endPosition = Integer.parseInt((String) dataSet.getRow().getValue(2));
 -                final int width = 1 + endPosition - beginPosition;
 -                columnSpecs.add(new FixedWidthColumnSpec(name, width));
 -            }
 -        }
 -
 -        return new FixedWidthConfiguration(encoding, columnSpecs, failOnInconsistentLineWidth);
 -    }
 -
 -    /**
 -     * Reads a {@link FixedWidthConfiguration} based on a SAS INPUT declaration.
 -     * The reader method also optionally will look for a LABEL defintion for
 -     * column naming.
 -     * 
 -     * @param encoding
 -     * @param resource
 -     *            the format file resource
 -     * @param failOnInconsistentLineWidth
 -     * @return a {@link FixedWidthConfiguration} object to use
 -     */
 -    public FixedWidthConfiguration readFromSasInputDefinition(String encoding, Resource resource,
 -            boolean failOnInconsistentLineWidth) {
 -
 -        final Map<String, Integer> inputWidthDeclarations = new LinkedHashMap<>();
 -        final Map<String, String> labelDeclarations = new HashMap<>();
 -
 -        resource.read(new Action<InputStream>() {
 -
 -            private boolean inInputSection = false;
 -            private boolean inLabelSection = false;
 -
 -            @Override
 -            public void run(InputStream in) throws Exception {
 -                try (final BufferedReader reader = new BufferedReader(new InputStreamReader(in))) {
 -                    for (String line = reader.readLine(); line != null; line = reader.readLine()) {
 -                        processLine(line);
 -                    }
 -                }
 -            }
 -
 -            private void processLine(String line) {
 -                line = line.trim();
 -                if (line.isEmpty()) {
 -                    return;
 -                }
 -                if (";".equals(line)) {
 -                    inInputSection = false;
 -                    inLabelSection = false;
 -                    return;
 -                } else if ("INPUT".equals(line)) {
 -                    inInputSection = true;
 -                    return;
 -                } else if ("LABEL".equals(line)) {
 -                    inLabelSection = true;
 -                    return;
 -                }
 -
 -                if (inInputSection) {
 -                    final Matcher matcher = PATTERN_SAS_INPUT_LINE.matcher(line);
 -                    if (matcher.matches()) {
 -                        final String positionSpec = matcher.group(1);
 -                        final String nameSpec = matcher.group(2);
 -                        final int width = Integer.parseInt(matcher.group(3));
 -                        logger.debug("Parsed INPUT line \"{}\": position={}, name={}, width={}", line, positionSpec,
 -                                nameSpec, width);
 -                        inputWidthDeclarations.put(nameSpec, width);
 -                    } else {
 -                        logger.debug("Failed to parse/recognize INPUT line \"{}\"", line);
 -                    }
 -                } else if (inLabelSection) {
 -                    final Matcher matcher = PATTERN_SAS_LABEL_LINE.matcher(line);
 -                    if (matcher.matches()) {
 -                        final String nameSpec = matcher.group(1);
 -                        final String labelSpec = matcher.group(2);
 -                        logger.debug("Parsed LABEL line \"{}\": name={}, label={}", line, nameSpec, labelSpec);
 -                        labelDeclarations.put(nameSpec, labelSpec);
 -                    } else {
 -                        logger.debug("Failed to parse/recognize LABEL line \"{}\"", line);
 -                    }
 -                }
 -
 -                if (line.endsWith(";")) {
 -                    inInputSection = false;
 -                    inLabelSection = false;
 -                }
 -            }
 -        });
 -
 -        final List<FixedWidthColumnSpec> columnSpecs = new ArrayList<>();
 -        for (Entry<String, Integer> entry : inputWidthDeclarations.entrySet()) {
 -            final String columnKey = entry.getKey();
 -            final Integer columnWidth = entry.getValue();
 -            final String columnLabel = labelDeclarations.get(columnKey);
 -            final String columnName = columnLabel == null ? columnKey : columnLabel;
 -            columnSpecs.add(new FixedWidthColumnSpec(columnName, columnWidth));
 -        }
 -
 -        return new FixedWidthConfiguration(encoding, columnSpecs, failOnInconsistentLineWidth);
 -    }
 -
 -}
++/**
++ * 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.metamodel.fixedwidth;
++
++import java.io.BufferedReader;
++import java.io.InputStream;
++import java.io.InputStreamReader;
++import java.util.ArrayList;
++import java.util.HashMap;
++import java.util.LinkedHashMap;
++import java.util.List;
++import java.util.Map;
++import java.util.Map.Entry;
++import java.util.regex.Matcher;
++import java.util.regex.Pattern;
++
++import org.apache.metamodel.csv.CsvConfiguration;
++import org.apache.metamodel.csv.CsvDataContext;
++import org.apache.metamodel.data.DataSet;
++import org.apache.metamodel.schema.Table;
++import org.apache.metamodel.util.Action;
++import org.apache.metamodel.util.Resource;
++import org.slf4j.Logger;
++import org.slf4j.LoggerFactory;
++
++/**
++ * Object capable of reading fixed width metadata from external sources and
++ * thereby producing an appropriate {@link FixedWidthConfiguration} to use with
++ * a {@link FixedWidthDataContext}.
++ */
++public class FixedWidthConfigurationReader {
++
++    private static final Logger logger = LoggerFactory.getLogger(FixedWidthConfigurationReader.class);
++
++    // example: @1 COL1 $char1.
++    private final Pattern PATTERN_SAS_INPUT_LINE = Pattern.compile("\\@(\\d+) (.+) .*?(\\d+)\\.");
++
++    // example: COL1 "Record type"
++    private final Pattern PATTERN_SAS_LABEL_LINE = Pattern.compile("(.+) \\\"(.+)\\\"");
++
++    /**
++     * Reads a {@link FixedWidthConfiguration} based on a SAS 'format file',
++     * <a href=
++     * "http://support.sas.com/documentation/cdl/en/etlug/67323/HTML/default/viewer.htm#p0h03yig7fp1qan1arghp3lwjqi6.htm">
++     * described here</a>.
++     * 
++     * @param encoding
++     * @param resource
++     *            the format file resource
++     * @param failOnInconsistentLineWidth
++     * @return a {@link FixedWidthConfiguration} object to use
++     */
++    public FixedWidthConfiguration readFromSasFormatFile(String encoding, Resource resource,
++            boolean failOnInconsistentLineWidth) {
++        final List<FixedWidthColumnSpec> columnSpecs = new ArrayList<>();
++
++        final CsvDataContext dataContext = new CsvDataContext(resource, new CsvConfiguration());
++        final Table table = dataContext.getDefaultSchema().getTable(0);
++        try (final DataSet dataSet = dataContext.query().from(table).select("Name", "BeginPosition", "EndPosition")
++                .execute()) {
++            while (dataSet.next()) {
++                final String name = (String) dataSet.getRow().getValue(0);
++                final int beginPosition = Integer.parseInt((String) dataSet.getRow().getValue(1));
++                final int endPosition = Integer.parseInt((String) dataSet.getRow().getValue(2));
++                final int width = 1 + endPosition - beginPosition;
++                columnSpecs.add(new FixedWidthColumnSpec(name, width));
++            }
++        }
++
++        return new FixedWidthConfiguration(encoding, columnSpecs, failOnInconsistentLineWidth);
++    }
++
++    /**
++     * Reads a {@link FixedWidthConfiguration} based on a SAS INPUT declaration.
++     * The reader method also optionally will look for a LABEL defintion for
++     * column naming.
++     * 
++     * @param encoding
++     * @param resource
++     *            the format file resource
++     * @param failOnInconsistentLineWidth
++     * @return a {@link FixedWidthConfiguration} object to use
++     */
++    public FixedWidthConfiguration readFromSasInputDefinition(String encoding, Resource resource,
++            boolean failOnInconsistentLineWidth) {
++
++        final Map<String, Integer> inputWidthDeclarations = new LinkedHashMap<>();
++        final Map<String, String> labelDeclarations = new HashMap<>();
++
++        resource.read(new Action<InputStream>() {
++
++            private boolean inInputSection = false;
++            private boolean inLabelSection = false;
++
++            @Override
++            public void run(InputStream in) throws Exception {
++                try (final BufferedReader reader = new BufferedReader(new InputStreamReader(in))) {
++                    for (String line = reader.readLine(); line != null; line = reader.readLine()) {
++                        processLine(line);
++                    }
++                }
++            }
++
++            private void processLine(String line) {
++                line = line.trim();
++                if (line.isEmpty()) {
++                    return;
++                }
++                if (";".equals(line)) {
++                    inInputSection = false;
++                    inLabelSection = false;
++                    return;
++                } else if ("INPUT".equals(line)) {
++                    inInputSection = true;
++                    return;
++                } else if ("LABEL".equals(line)) {
++                    inLabelSection = true;
++                    return;
++                }
++
++                if (inInputSection) {
++                    final Matcher matcher = PATTERN_SAS_INPUT_LINE.matcher(line);
++                    if (matcher.matches()) {
++                        final String positionSpec = matcher.group(1);
++                        final String nameSpec = matcher.group(2);
++                        final int width = Integer.parseInt(matcher.group(3));
++                        logger.debug("Parsed INPUT line \"{}\": position={}, name={}, width={}", line, positionSpec,
++                                nameSpec, width);
++                        inputWidthDeclarations.put(nameSpec, width);
++                    } else {
++                        logger.debug("Failed to parse/recognize INPUT line \"{}\"", line);
++                    }
++                } else if (inLabelSection) {
++                    final Matcher matcher = PATTERN_SAS_LABEL_LINE.matcher(line);
++                    if (matcher.matches()) {
++                        final String nameSpec = matcher.group(1);
++                        final String labelSpec = matcher.group(2);
++                        logger.debug("Parsed LABEL line \"{}\": name={}, label={}", line, nameSpec, labelSpec);
++                        labelDeclarations.put(nameSpec, labelSpec);
++                    } else {
++                        logger.debug("Failed to parse/recognize LABEL line \"{}\"", line);
++                    }
++                }
++
++                if (line.endsWith(";")) {
++                    inInputSection = false;
++                    inLabelSection = false;
++                }
++            }
++        });
++
++        final List<FixedWidthColumnSpec> columnSpecs = new ArrayList<>();
++        for (Entry<String, Integer> entry : inputWidthDeclarations.entrySet()) {
++            final String columnKey = entry.getKey();
++            final Integer columnWidth = entry.getValue();
++            final String columnLabel = labelDeclarations.get(columnKey);
++            final String columnName = columnLabel == null ? columnKey : columnLabel;
++            columnSpecs.add(new FixedWidthColumnSpec(columnName, columnWidth));
++        }
++
++        return new FixedWidthConfiguration(encoding, columnSpecs, failOnInconsistentLineWidth);
++    }
++
++}

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/fixedwidth/src/test/java/org/apache/metamodel/fixedwidth/FixedWidthConfigurationReaderTest.java
----------------------------------------------------------------------
diff --cc fixedwidth/src/test/java/org/apache/metamodel/fixedwidth/FixedWidthConfigurationReaderTest.java
index 0000000,eb57233..c34b294
mode 000000,100644..100644
--- a/fixedwidth/src/test/java/org/apache/metamodel/fixedwidth/FixedWidthConfigurationReaderTest.java
+++ b/fixedwidth/src/test/java/org/apache/metamodel/fixedwidth/FixedWidthConfigurationReaderTest.java
@@@ -1,0 -1,89 +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.metamodel.fixedwidth;
 -
 -import static org.junit.Assert.*;
 -
 -import java.util.Arrays;
 -
 -import org.apache.metamodel.DataContext;
 -import org.apache.metamodel.data.DataSet;
 -import org.apache.metamodel.schema.Table;
 -import org.apache.metamodel.util.FileResource;
 -import org.apache.metamodel.util.Resource;
 -import org.junit.Test;
 -
 -public class FixedWidthConfigurationReaderTest {
 -
 -    private final FileResource dataResource = new FileResource("src/test/resources/metadata_spec1/data.txt");
 -
 -    @Test
 -    public void testReadConfigurationFromSasFormatFile() throws Exception {
 -        final FixedWidthConfigurationReader reader = new FixedWidthConfigurationReader();
 -        final Resource resource = new FileResource("src/test/resources/metadata_spec1/sas-formatfile-metadata.txt");
 -        assertTrue(resource.isExists());
 -
 -        final FixedWidthConfiguration configuration = reader.readFromSasFormatFile("UTF8", resource, false);
 -        assertEquals("[1, 20, 2]", Arrays.toString(configuration.getValueWidths()));
 -
 -        final FixedWidthDataContext dataContext = new FixedWidthDataContext(dataResource, configuration);
 -
 -        performAssertionsOnSpec1(dataContext);
 -    }
 -    
 -    @Test
 -    public void testReadConfigurationFromSasInputMetadata() throws Exception {
 -        final FixedWidthConfigurationReader reader = new FixedWidthConfigurationReader();
 -        final Resource resource = new FileResource("src/test/resources/metadata_spec1/sas-input-metadata.txt");
 -        assertTrue(resource.isExists());
 -
 -        final FixedWidthConfiguration configuration = reader.readFromSasInputDefinition("UTF8", resource, false);
 -        assertEquals("[1, 20, 2]", Arrays.toString(configuration.getValueWidths()));
 -
 -        final FixedWidthDataContext dataContext = new FixedWidthDataContext(dataResource, configuration);
 -
 -        performAssertionsOnSpec1(dataContext);
 -    }
 -
 -    /**
 -     * Shared assertions section once the 'metadata_spec1' {@link DataContext}
 -     * has been loaded.
 -     * 
 -     * @param dataContext
 -     */
 -    private void performAssertionsOnSpec1(FixedWidthDataContext dataContext) {
 -        final Table table = dataContext.getDefaultSchema().getTable(0);
 -        final String[] columnNames = table.getColumnNames();
 -        assertEquals("[Record type, Description, Initials]", Arrays.toString(columnNames));
 -
 -        try (final DataSet dataSet = dataContext.query().from(table).selectAll().execute()) {
 -            assertTrue(dataSet.next());
 -            assertEquals("Row[values=[P, Kasper Sorensen, KS]]", dataSet.getRow().toString());
 -            assertTrue(dataSet.next());
 -            assertEquals("Row[values=[C, Human Inference, HI]]", dataSet.getRow().toString());
 -            assertTrue(dataSet.next());
 -            assertEquals("Row[values=[P, Ankit Kumar, AK]]", dataSet.getRow().toString());
 -            assertTrue(dataSet.next());
 -            assertEquals("Row[values=[C, Stratio, S]]", dataSet.getRow().toString());
 -            assertTrue(dataSet.next());
 -            assertEquals("Row[values=[U, Unknown, ]]", dataSet.getRow().toString());
 -            assertFalse(dataSet.next());
 -        }
 -    }
 -}
++/**
++ * 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.metamodel.fixedwidth;
++
++import static org.junit.Assert.*;
++
++import java.util.Arrays;
++
++import org.apache.metamodel.DataContext;
++import org.apache.metamodel.data.DataSet;
++import org.apache.metamodel.schema.Table;
++import org.apache.metamodel.util.FileResource;
++import org.apache.metamodel.util.Resource;
++import org.junit.Test;
++
++public class FixedWidthConfigurationReaderTest {
++
++    private final FileResource dataResource = new FileResource("src/test/resources/metadata_spec1/data.txt");
++
++    @Test
++    public void testReadConfigurationFromSasFormatFile() throws Exception {
++        final FixedWidthConfigurationReader reader = new FixedWidthConfigurationReader();
++        final Resource resource = new FileResource("src/test/resources/metadata_spec1/sas-formatfile-metadata.txt");
++        assertTrue(resource.isExists());
++
++        final FixedWidthConfiguration configuration = reader.readFromSasFormatFile("UTF8", resource, false);
++        assertEquals("[1, 20, 2]", Arrays.toString(configuration.getValueWidths()));
++
++        final FixedWidthDataContext dataContext = new FixedWidthDataContext(dataResource, configuration);
++
++        performAssertionsOnSpec1(dataContext);
++    }
++    
++    @Test
++    public void testReadConfigurationFromSasInputMetadata() throws Exception {
++        final FixedWidthConfigurationReader reader = new FixedWidthConfigurationReader();
++        final Resource resource = new FileResource("src/test/resources/metadata_spec1/sas-input-metadata.txt");
++        assertTrue(resource.isExists());
++
++        final FixedWidthConfiguration configuration = reader.readFromSasInputDefinition("UTF8", resource, false);
++        assertEquals("[1, 20, 2]", Arrays.toString(configuration.getValueWidths()));
++
++        final FixedWidthDataContext dataContext = new FixedWidthDataContext(dataResource, configuration);
++
++        performAssertionsOnSpec1(dataContext);
++    }
++
++    /**
++     * Shared assertions section once the 'metadata_spec1' {@link DataContext}
++     * has been loaded.
++     * 
++     * @param dataContext
++     */
++    private void performAssertionsOnSpec1(FixedWidthDataContext dataContext) {
++        final Table table = dataContext.getDefaultSchema().getTable(0);
++        final String[] columnNames = table.getColumnNames();
++        assertEquals("[Record type, Description, Initials]", Arrays.toString(columnNames));
++
++        try (final DataSet dataSet = dataContext.query().from(table).selectAll().execute()) {
++            assertTrue(dataSet.next());
++            assertEquals("Row[values=[P, Kasper Sorensen, KS]]", dataSet.getRow().toString());
++            assertTrue(dataSet.next());
++            assertEquals("Row[values=[C, Human Inference, HI]]", dataSet.getRow().toString());
++            assertTrue(dataSet.next());
++            assertEquals("Row[values=[P, Ankit Kumar, AK]]", dataSet.getRow().toString());
++            assertTrue(dataSet.next());
++            assertEquals("Row[values=[C, Stratio, S]]", dataSet.getRow().toString());
++            assertTrue(dataSet.next());
++            assertEquals("Row[values=[U, Unknown, ]]", dataSet.getRow().toString());
++            assertFalse(dataSet.next());
++        }
++    }
++}

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/fixedwidth/src/test/resources/metadata_spec1/data.txt
----------------------------------------------------------------------
diff --cc fixedwidth/src/test/resources/metadata_spec1/data.txt
index 0000000,785a539..ac055c9
mode 000000,100644..100644
--- a/fixedwidth/src/test/resources/metadata_spec1/data.txt
+++ b/fixedwidth/src/test/resources/metadata_spec1/data.txt
@@@ -1,0 -1,5 +1,5 @@@
 -PKasper Sorensen     KS
 -CHuman Inference     HI
 -PAnkit Kumar         AK
 -CStratio             S 
 -UUnknown               
++PKasper Sorensen     KS
++CHuman Inference     HI
++PAnkit Kumar         AK
++CStratio             S 
++UUnknown               

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/fixedwidth/src/test/resources/metadata_spec1/sas-formatfile-metadata.txt
----------------------------------------------------------------------
diff --cc fixedwidth/src/test/resources/metadata_spec1/sas-formatfile-metadata.txt
index 0000000,9bbe411..38b0e04
mode 000000,100644..100644
--- a/fixedwidth/src/test/resources/metadata_spec1/sas-formatfile-metadata.txt
+++ b/fixedwidth/src/test/resources/metadata_spec1/sas-formatfile-metadata.txt
@@@ -1,0 -1,4 +1,4 @@@
 -Name,SASColumnType,BeginPosition,EndPosition,ReadFlag,Desc,SASFormat,SASInformat
 -Record type,C,1,1,y,Record Type,$char.,$char.
 -Description,C,2,21,y,Description of record,$char.,$char.
 -Initials,C,22,23,y,Initials of record,,
++Name,SASColumnType,BeginPosition,EndPosition,ReadFlag,Desc,SASFormat,SASInformat
++Record type,C,1,1,y,Record Type,$char.,$char.
++Description,C,2,21,y,Description of record,$char.,$char.
++Initials,C,22,23,y,Initials of record,,

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/fixedwidth/src/test/resources/metadata_spec1/sas-input-metadata.txt
----------------------------------------------------------------------
diff --cc fixedwidth/src/test/resources/metadata_spec1/sas-input-metadata.txt
index 0000000,f12e418..6839a9b
mode 000000,100644..100644
--- a/fixedwidth/src/test/resources/metadata_spec1/sas-input-metadata.txt
+++ b/fixedwidth/src/test/resources/metadata_spec1/sas-input-metadata.txt
@@@ -1,0 -1,19 +1,19 @@@
 -INPUT
 -
 -   @1 COL1 $char1.
 -
 -   @2 COL2 $char20.
 -
 -   @22 COL3 $char2.
 -   
 -;
 -
 -LABEL
 -
 -   COL1 "Record type"
 -
 -   COL2 "Description"
 -
 -   COL3 "Initials"
 -
 -;
++INPUT
++
++   @1 COL1 $char1.
++
++   @2 COL2 $char20.
++
++   @22 COL3 $char2.
++   
++;
++
++LABEL
++
++   COL1 "Record type"
++
++   COL2 "Description"
++
++   COL3 "Initials"
++
++;

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/full/pom.xml
----------------------------------------------------------------------

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/mongodb/common/pom.xml
----------------------------------------------------------------------
diff --cc mongodb/common/pom.xml
index 0000000,850d2f7..9675d9e
mode 000000,100644..100644
--- a/mongodb/common/pom.xml
+++ b/mongodb/common/pom.xml
@@@ -1,0 -1,67 +1,67 @@@
+ <?xml version="1.0" encoding="UTF-8" ?>
+ <!--
+ 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.
+ -->
+ <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+ 	<parent>
+ 		<artifactId>MetaModel-mongodb</artifactId>
+ 		<groupId>org.apache.metamodel</groupId>
 -		<version>4.5.3-SNAPSHOT</version>
++		<version>5.0-SNAPSHOT</version>
+ 	</parent>
+ 	<modelVersion>4.0.0</modelVersion>
+ 	<artifactId>MetaModel-mongodb-common</artifactId>
+ 	<name>MetaModel module for MongoDB commons</name>
+ 	
+ 	<dependencies>
+ 		<dependency>
+ 			<groupId>org.apache.metamodel</groupId>
+ 			<artifactId>MetaModel-core</artifactId>
+ 			<version>${project.version}</version>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>org.mongodb</groupId>
+ 			<artifactId>mongo-java-driver</artifactId>
+ 			<version>3.1.0</version>
+ 			<scope>provided</scope>
+ 		</dependency>
+ 
+ 		<!-- Test dependencies -->
+ 		<dependency>
+ 			<groupId>org.apache.metamodel</groupId>
+ 			<artifactId>MetaModel-jdbc</artifactId>
+ 			<version>${project.version}</version>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>org.apache.derby</groupId>
+ 			<artifactId>derby</artifactId>
+ 			<version>10.8.1.2</version>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>org.slf4j</groupId>
+ 			<artifactId>slf4j-nop</artifactId>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>junit</groupId>
+ 			<artifactId>junit</artifactId>
+ 			<scope>test</scope>
+ 		</dependency>
+ 	</dependencies>
+ </project>

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/mongodb/mongo2/pom.xml
----------------------------------------------------------------------
diff --cc mongodb/mongo2/pom.xml
index 0000000,4905102..8cd2540
mode 000000,100644..100644
--- a/mongodb/mongo2/pom.xml
+++ b/mongodb/mongo2/pom.xml
@@@ -1,0 -1,70 +1,70 @@@
+ <?xml version="1.0" encoding="UTF-8" ?>
+ <!--
+ 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.
+ -->
+ <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+ 	<parent>
+ 		<artifactId>MetaModel-mongodb</artifactId>
+ 		<groupId>org.apache.metamodel</groupId>
 -		<version>4.5.3-SNAPSHOT</version>
++		<version>5.0-SNAPSHOT</version>
+ 	</parent>
+ 	<modelVersion>4.0.0</modelVersion>
+ 	<artifactId>MetaModel-mongodb-mongo2</artifactId>
+ 	<name>MetaModel module for MongoDB 2.x</name>
+ 	<dependencies>
+ 		<dependency>
+ 			<groupId>org.apache.metamodel</groupId>
+ 			<artifactId>MetaModel-core</artifactId>
+ 			<version>${project.version}</version>
+ 		</dependency>
+ 		<dependency>
+             <groupId>org.apache.metamodel</groupId>
+             <artifactId>MetaModel-mongodb-common</artifactId>
+             <version>${project.version}</version>
+         </dependency>
+ 		<dependency>
+ 			<groupId>org.mongodb</groupId>
+ 			<artifactId>mongo-java-driver</artifactId>
+ 			<version>2.14.0</version>
+ 		</dependency>
+ 
+ 		<!-- Test dependencies -->
+ 		<dependency>
+ 			<groupId>org.apache.metamodel</groupId>
+ 			<artifactId>MetaModel-jdbc</artifactId>
+ 			<version>${project.version}</version>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>org.apache.derby</groupId>
+ 			<artifactId>derby</artifactId>
+ 			<version>10.8.1.2</version>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>org.slf4j</groupId>
+ 			<artifactId>slf4j-nop</artifactId>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>junit</groupId>
+ 			<artifactId>junit</artifactId>
+ 			<scope>test</scope>
+ 		</dependency>
+ 	</dependencies>
+ </project>

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/mongodb/mongo2/src/main/java/org/apache/metamodel/mongodb/mongo2/MongoDbDataContext.java
----------------------------------------------------------------------
diff --cc mongodb/mongo2/src/main/java/org/apache/metamodel/mongodb/mongo2/MongoDbDataContext.java
index 0000000,cfeb836..d2095e9
mode 000000,100644..100644
--- a/mongodb/mongo2/src/main/java/org/apache/metamodel/mongodb/mongo2/MongoDbDataContext.java
+++ b/mongodb/mongo2/src/main/java/org/apache/metamodel/mongodb/mongo2/MongoDbDataContext.java
@@@ -1,0 -1,528 +1,530 @@@
+ /**
+  * 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.metamodel.mongodb.mongo2;
+ 
+ import java.util.ArrayList;
+ import java.util.HashSet;
+ import java.util.List;
+ import java.util.Map.Entry;
+ import java.util.Set;
+ import java.util.SortedMap;
+ import java.util.TreeMap;
+ import java.util.regex.Pattern;
+ 
+ import org.apache.metamodel.DataContext;
+ import org.apache.metamodel.MetaModelException;
+ import org.apache.metamodel.QueryPostprocessDataContext;
+ import org.apache.metamodel.UpdateScript;
++import org.apache.metamodel.UpdateSummary;
+ import org.apache.metamodel.UpdateableDataContext;
+ import org.apache.metamodel.data.DataSet;
+ import org.apache.metamodel.data.DataSetHeader;
+ import org.apache.metamodel.data.InMemoryDataSet;
+ import org.apache.metamodel.data.Row;
+ import org.apache.metamodel.data.SimpleDataSetHeader;
+ import org.apache.metamodel.mongodb.common.MongoDBUtils;
+ import org.apache.metamodel.mongodb.common.MongoDbTableDef;
+ import org.apache.metamodel.query.FilterItem;
+ import org.apache.metamodel.query.FromItem;
+ import org.apache.metamodel.query.OperatorType;
+ import org.apache.metamodel.query.Query;
+ import org.apache.metamodel.query.SelectItem;
+ import org.apache.metamodel.schema.Column;
+ import org.apache.metamodel.schema.ColumnType;
+ import org.apache.metamodel.schema.ColumnTypeImpl;
+ import org.apache.metamodel.schema.MutableColumn;
+ import org.apache.metamodel.schema.MutableSchema;
+ import org.apache.metamodel.schema.MutableTable;
+ import org.apache.metamodel.schema.Schema;
+ import org.apache.metamodel.schema.Table;
+ import org.apache.metamodel.util.SimpleTableDef;
+ import org.bson.types.ObjectId;
+ import org.slf4j.Logger;
+ import org.slf4j.LoggerFactory;
+ 
+ import com.mongodb.BasicDBList;
+ import com.mongodb.BasicDBObject;
+ import com.mongodb.DB;
+ import com.mongodb.DBCollection;
+ import com.mongodb.DBCursor;
+ import com.mongodb.DBObject;
+ import com.mongodb.WriteConcern;
+ 
+ /**
+  * DataContext implementation for MongoDB.
+  *
+  * Since MongoDB has no schema, a virtual schema will be used in this
+  * DataContext. This implementation supports either automatic discovery of a
+  * schema or manual specification of a schema, through the
+  * {@link MongoDbTableDef} class.
+  */
+ public class MongoDbDataContext extends QueryPostprocessDataContext implements UpdateableDataContext {
+ 
+     private static final Logger logger = LoggerFactory.getLogger(MongoDbDataSet.class);
+ 
+     private final DB _mongoDb;
+     private final SimpleTableDef[] _tableDefs;
+     private WriteConcernAdvisor _writeConcernAdvisor;
+     private Schema _schema;
+ 
+     /**
+      * Constructor available for backwards compatibility
+      *
+      * @deprecated use {@link #MongoDbDataContext(DB, SimpleTableDef...)}
+      *             instead
+      */
+     @Deprecated
+     public MongoDbDataContext(DB mongoDb, MongoDbTableDef... tableDefs) {
+         this(mongoDb, (SimpleTableDef[]) tableDefs);
+     }
+ 
+     /**
+      * Constructs a {@link MongoDbDataContext}. This constructor accepts a
+      * custom array of {@link MongoDbTableDef}s which allows the user to define
+      * his own view on the collections in the database.
+      *
+      * @param mongoDb
+      *            the mongo db connection
+      * @param tableDefs
+      *            an array of {@link MongoDbTableDef}s, which define the table
+      *            and column model of the mongo db collections. (consider using
+      *            {@link #detectSchema(DB)} or {@link #detectTable(DB, String)}
+      *            ).
+      */
+     public MongoDbDataContext(DB mongoDb, SimpleTableDef... tableDefs) {
+         _mongoDb = mongoDb;
+         _tableDefs = tableDefs;
+         _schema = null;
+     }
+ 
+     /**
+      * Constructs a {@link MongoDbDataContext} and automatically detects the
+      * schema structure/view on all collections (see {@link #detectSchema(DB)}).
+      *
+      * @param mongoDb
+      *            the mongo db connection
+      */
+     public MongoDbDataContext(DB mongoDb) {
+         this(mongoDb, detectSchema(mongoDb));
+     }
+ 
+     /**
+      * Performs an analysis of the available collections in a Mongo {@link DB}
+      * instance and tries to detect the table's structure based on the first
+      * 1000 documents in each collection.
+      *
+      * @param db
+      *            the mongo db to inspect
+      * @return a mutable schema instance, useful for further fine tuning by the
+      *         user.
+      * @see #detectTable(DB, String)
+      */
+     public static SimpleTableDef[] detectSchema(DB db) {
+         Set<String> collectionNames = db.getCollectionNames();
+         SimpleTableDef[] result = new SimpleTableDef[collectionNames.size()];
+         int i = 0;
+         for (String collectionName : collectionNames) {
+             SimpleTableDef table = detectTable(db, collectionName);
+             result[i] = table;
+             i++;
+         }
+         return result;
+     }
+ 
+     /**
+      * Performs an analysis of an available collection in a Mongo {@link DB}
+      * instance and tries to detect the table structure based on the first 1000
+      * documents in the collection.
+      *
+      * @param db
+      *            the mongo DB
+      * @param collectionName
+      *            the name of the collection
+      * @return a table definition for mongo db.
+      */
+     public static SimpleTableDef detectTable(DB db, String collectionName) {
+         final DBCollection collection = db.getCollection(collectionName);
+         final DBCursor cursor = collection.find().limit(1000);
+ 
+         final SortedMap<String, Set<Class<?>>> columnsAndTypes = new TreeMap<String, Set<Class<?>>>();
+         while (cursor.hasNext()) {
+             DBObject object = cursor.next();
+             Set<String> keysInObject = object.keySet();
+             for (String key : keysInObject) {
+                 Set<Class<?>> types = columnsAndTypes.get(key);
+                 if (types == null) {
+                     types = new HashSet<Class<?>>();
+                     columnsAndTypes.put(key, types);
+                 }
+                 Object value = object.get(key);
+                 if (value != null) {
+                     types.add(value.getClass());
+                 }
+             }
+         }
+         cursor.close();
+ 
+         final String[] columnNames = new String[columnsAndTypes.size()];
+         final ColumnType[] columnTypes = new ColumnType[columnsAndTypes.size()];
+ 
+         int i = 0;
+         for (Entry<String, Set<Class<?>>> columnAndTypes : columnsAndTypes.entrySet()) {
+             final String columnName = columnAndTypes.getKey();
+             final Set<Class<?>> columnTypeSet = columnAndTypes.getValue();
+             final Class<?> columnType;
+             if (columnTypeSet.size() == 1) {
+                 columnType = columnTypeSet.iterator().next();
+             } else {
+                 columnType = Object.class;
+             }
+             columnNames[i] = columnName;
+             if (columnType == ObjectId.class) {
+                 columnTypes[i] = ColumnType.ROWID;
+             } else {
+                 columnTypes[i] = ColumnTypeImpl.convertColumnType(columnType);
+             }
+             i++;
+         }
+ 
+         return new SimpleTableDef(collectionName, columnNames, columnTypes);
+     }
+ 
+     @Override
+     protected Schema getMainSchema() throws MetaModelException {
+         if (_schema == null) {
+             MutableSchema schema = new MutableSchema(getMainSchemaName());
+             for (SimpleTableDef tableDef : _tableDefs) {
+ 
+                 MutableTable table = tableDef.toTable().setSchema(schema);
+                 Column[] rowIdColumns = table.getColumnsOfType(ColumnType.ROWID);
+                 for (Column column : rowIdColumns) {
+                     if (column instanceof MutableColumn) {
+                         ((MutableColumn) column).setPrimaryKey(true);
+                     }
+                 }
+ 
+                 schema.addTable(table);
+             }
+ 
+             _schema = schema;
+         }
+         return _schema;
+     }
+ 
+     @Override
+     protected String getMainSchemaName() throws MetaModelException {
+         return _mongoDb.getName();
+     }
+ 
+     @Override
+     protected Number executeCountQuery(Table table, List<FilterItem> whereItems, boolean functionApproximationAllowed) {
+         final DBCollection collection = _mongoDb.getCollection(table.getName());
+ 
+         final DBObject query = createMongoDbQuery(table, whereItems);
+ 
+         logger.info("Executing MongoDB 'count' query: {}", query);
+         final long count = collection.count(query);
+ 
+         return count;
+     }
+ 
+     @Override
+     protected Row executePrimaryKeyLookupQuery(Table table, List<SelectItem> selectItems, Column primaryKeyColumn,
+             Object keyValue) {
+         final DBCollection collection = _mongoDb.getCollection(table.getName());
+ 
+         List<FilterItem> whereItems = new ArrayList<FilterItem>();
+         SelectItem selectItem = new SelectItem(primaryKeyColumn);
+         FilterItem primaryKeyWhereItem = new FilterItem(selectItem, OperatorType.EQUALS_TO, keyValue);
+         whereItems.add(primaryKeyWhereItem);
+         final DBObject query = createMongoDbQuery(table, whereItems);
+         final DBObject resultDBObject = collection.findOne(query);
+ 
+         DataSetHeader header = new SimpleDataSetHeader(selectItems);
+ 
+         Row row = MongoDBUtils.toRow(resultDBObject, header);
+ 
+         return row;
+     }
+ 
+     @Override
+     public DataSet executeQuery(Query query) {
+         // Check for queries containing only simple selects and where clauses,
+         // or if it is a COUNT(*) query.
+ 
+         // if from clause only contains a main schema table
+         List<FromItem> fromItems = query.getFromClause().getItems();
+         if (fromItems.size() == 1 && fromItems.get(0).getTable() != null
+                 && fromItems.get(0).getTable().getSchema() == _schema) {
+             final Table table = fromItems.get(0).getTable();
+ 
+             // if GROUP BY, HAVING and ORDER BY clauses are not specified
+             if (query.getGroupByClause().isEmpty() && query.getHavingClause().isEmpty()
+                     && query.getOrderByClause().isEmpty()) {
+ 
+                 final List<FilterItem> whereItems = query.getWhereClause().getItems();
+ 
+                 // if all of the select items are "pure" column selection
+                 boolean allSelectItemsAreColumns = true;
+                 List<SelectItem> selectItems = query.getSelectClause().getItems();
+ 
+                 // if it is a
+                 // "SELECT [columns] FROM [table] WHERE [conditions]"
+                 // query.
+                 for (SelectItem selectItem : selectItems) {
+                     if (selectItem.getFunction() != null || selectItem.getColumn() == null) {
+                         allSelectItemsAreColumns = false;
+                         break;
+                     }
+                 }
+ 
+                 if (allSelectItemsAreColumns) {
+                     logger.debug("Query can be expressed in full MongoDB, no post processing needed.");
+ 
+                     // prepare for a non-post-processed query
+                     Column[] columns = new Column[selectItems.size()];
+                     for (int i = 0; i < columns.length; i++) {
+                         columns[i] = selectItems.get(i).getColumn();
+                     }
+ 
+                     // checking if the query is a primary key lookup query
+                     if (whereItems.size() == 1) {
+                         final FilterItem whereItem = whereItems.get(0);
+                         final SelectItem selectItem = whereItem.getSelectItem();
+                         if (!whereItem.isCompoundFilter() && selectItem != null && selectItem.getColumn() != null) {
+                             final Column column = selectItem.getColumn();
+                             if (column.isPrimaryKey() && OperatorType.EQUALS_TO.equals(whereItem.getOperator())) {
+                                 logger.debug("Query is a primary key lookup query. Trying executePrimaryKeyLookupQuery(...)");
+                                 final Object operand = whereItem.getOperand();
+                                 final Row row = executePrimaryKeyLookupQuery(table, selectItems, column, operand);
+                                 if (row == null) {
+                                     logger.debug("DataContext did not return any primary key lookup query results. Proceeding "
+                                             + "with manual lookup.");
+                                 } else {
+                                     final DataSetHeader header = new SimpleDataSetHeader(selectItems);
+                                     return new InMemoryDataSet(header, row);
+                                 }
+                             }
+                         }
+                     }
+ 
+                     int firstRow = (query.getFirstRow() == null ? 1 : query.getFirstRow());
+                     int maxRows = (query.getMaxRows() == null ? -1 : query.getMaxRows());
+ 
+                     final DataSet dataSet = materializeMainSchemaTableInternal(table, columns, whereItems, firstRow,
+                             maxRows, false);
+                     return dataSet;
+                 }
+             }
+         }
+ 
+         logger.debug("Query will be simplified for MongoDB and post processed.");
+         return super.executeQuery(query);
+     }
+ 
+     private DataSet materializeMainSchemaTableInternal(Table table, Column[] columns, List<FilterItem> whereItems,
+             int firstRow, int maxRows, boolean queryPostProcessed) {
+         final DBCollection collection = _mongoDb.getCollection(table.getName());
+ 
+         final DBObject query = createMongoDbQuery(table, whereItems);
+ 
+         logger.info("Executing MongoDB 'find' query: {}", query);
+         DBCursor cursor = collection.find(query);
+ 
+         if (maxRows > 0) {
+             cursor = cursor.limit(maxRows);
+         }
+         if (firstRow > 1) {
+             final int skip = firstRow - 1;
+             cursor = cursor.skip(skip);
+         }
+ 
+         return new MongoDbDataSet(cursor, columns, queryPostProcessed);
+     }
+ 
+     protected BasicDBObject createMongoDbQuery(Table table, List<FilterItem> whereItems) {
+         assert _schema == table.getSchema();
+ 
+         final BasicDBObject query = new BasicDBObject();
+         if (whereItems != null && !whereItems.isEmpty()) {
+             for (FilterItem item : whereItems) {
+                 convertToCursorObject(query, item);
+             }
+         }
+ 
+         return query;
+     }
+ 
+     private void convertToCursorObject(BasicDBObject query, FilterItem item) {
+         if (item.isCompoundFilter()) {
+ 
+             BasicDBList orList = new BasicDBList();
+ 
+             final FilterItem[] childItems = item.getChildItems();
+             for (FilterItem childItem : childItems) {
+                 BasicDBObject childObject = new BasicDBObject();
+                 convertToCursorObject(childObject, childItem);
+                 orList.add(childObject);
+             }
+ 
+             query.put("$or", orList);
+ 
+         } else {
+ 
+             final Column column = item.getSelectItem().getColumn();
+             final String columnName = column.getName();
+             final String operatorName = getOperatorName(item);
+ 
+             Object operand = item.getOperand();
+             if (ObjectId.isValid(String.valueOf(operand))) {
+                 operand = new ObjectId(String.valueOf(operand));
+             }
+ 
+             final BasicDBObject existingFilterObject = (BasicDBObject) query.get(columnName);
+             if (existingFilterObject == null) {
+                 if (operatorName == null) {
+                     if (OperatorType.LIKE.equals(item.getOperator())) {
+                         query.put(columnName, turnOperandIntoRegExp(operand));
+                     } else {
+                         query.put(columnName, operand);
+                     }
+                 } else {
+                     query.put(columnName, new BasicDBObject(operatorName, operand));
+                 }
+             } else {
+                 if (operatorName == null) {
+                     throw new IllegalStateException("Cannot retrieve records for a column with two EQUALS_TO operators");
+                 } else {
+                     existingFilterObject.append(operatorName, operand);
+                 }
+             }
+         }
+     }
+ 
+     private String getOperatorName(FilterItem item) {
+         final OperatorType operator = item.getOperator();
+ 
+         if (OperatorType.EQUALS_TO.equals(operator)) {
+             return null;
+         }
+         if (OperatorType.LIKE.equals(operator)) {
+             return null;
+         }
+         if (OperatorType.LESS_THAN.equals(operator)) {
+             return "$lt";
+         }
+         if (OperatorType.LESS_THAN_OR_EQUAL.equals(operator)) {
+             return "$lte";
+         }
+         if (OperatorType.GREATER_THAN.equals(operator)) {
+             return "$gt";
+         }
+         if (OperatorType.GREATER_THAN_OR_EQUAL.equals(operator)) {
+             return "$gte";
+         }
+         if (OperatorType.DIFFERENT_FROM.equals(operator)) {
+             return "$ne";
+         }
+         if (OperatorType.IN.equals(operator)) {
+             return "$in";
+         }
+ 
+         throw new IllegalStateException("Unsupported operator type: " + operator);
+     }
+ 
+     private Pattern turnOperandIntoRegExp(Object operand) {
+         StringBuilder operandAsRegExp = new StringBuilder(replaceWildCardLikeChars(operand.toString()));
+         operandAsRegExp.insert(0, "^").append("$");
+         return Pattern.compile(operandAsRegExp.toString(), Pattern.CASE_INSENSITIVE);
+     }
+ 
+     private String replaceWildCardLikeChars(String operand) {
+         return operand.replaceAll("%", ".*");
+     }
+ 
+     @Override
+     protected DataSet materializeMainSchemaTable(Table table, Column[] columns, int maxRows) {
+         return materializeMainSchemaTableInternal(table, columns, null, 1, maxRows, true);
+     }
+ 
+     @Override
+     protected DataSet materializeMainSchemaTable(Table table, Column[] columns, int firstRow, int maxRows) {
+         return materializeMainSchemaTableInternal(table, columns, null, firstRow, maxRows, true);
+     }
+ 
+     /**
+      * Executes an update with a specific {@link WriteConcernAdvisor}.
+      */
 -    public void executeUpdate(UpdateScript update, WriteConcernAdvisor writeConcernAdvisor) {
++    public UpdateSummary executeUpdate(UpdateScript update, WriteConcernAdvisor writeConcernAdvisor) {
+         MongoDbUpdateCallback callback = new MongoDbUpdateCallback(this, writeConcernAdvisor);
+         try {
+             update.run(callback);
+         } finally {
+             callback.close();
+         }
++        return callback.getUpdateSummary();
+     }
+ 
+     /**
+      * Executes an update with a specific {@link WriteConcern}.
+      */
 -    public void executeUpdate(UpdateScript update, WriteConcern writeConcern) {
 -        executeUpdate(update, new SimpleWriteConcernAdvisor(writeConcern));
++    public UpdateSummary executeUpdate(UpdateScript update, WriteConcern writeConcern) {
++        return executeUpdate(update, new SimpleWriteConcernAdvisor(writeConcern));
+     }
+ 
+     @Override
 -    public void executeUpdate(UpdateScript update) {
 -        executeUpdate(update, getWriteConcernAdvisor());
++    public UpdateSummary executeUpdate(UpdateScript update) {
++        return executeUpdate(update, getWriteConcernAdvisor());
+     }
+ 
+     /**
+      * Gets the {@link WriteConcernAdvisor} to use on
+      * {@link #executeUpdate(UpdateScript)} calls.
+      */
+     public WriteConcernAdvisor getWriteConcernAdvisor() {
+         if (_writeConcernAdvisor == null) {
+             return new DefaultWriteConcernAdvisor();
+         }
+         return _writeConcernAdvisor;
+     }
+ 
+     /**
+      * Sets a global {@link WriteConcern} advisor to use on
+      * {@link #executeUpdate(UpdateScript)}.
+      */
+     public void setWriteConcernAdvisor(WriteConcernAdvisor writeConcernAdvisor) {
+         _writeConcernAdvisor = writeConcernAdvisor;
+     }
+ 
+     /**
+      * Gets the {@link DB} instance that this {@link DataContext} is backed by.
+      */
+     public DB getMongoDb() {
+         return _mongoDb;
+     }
+ 
+     protected void addTable(MutableTable table) {
+         if (_schema instanceof MutableSchema) {
+             MutableSchema mutableSchema = (MutableSchema) _schema;
+             mutableSchema.addTable(table);
+         } else {
+             throw new UnsupportedOperationException("Schema is not mutable");
+         }
+     }
+ }

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/mongodb/mongo3/pom.xml
----------------------------------------------------------------------
diff --cc mongodb/mongo3/pom.xml
index 0000000,ae53158..4ff4fd7
mode 000000,100644..100644
--- a/mongodb/mongo3/pom.xml
+++ b/mongodb/mongo3/pom.xml
@@@ -1,0 -1,70 +1,70 @@@
+ <?xml version="1.0" encoding="UTF-8" ?>
+ <!--
+ 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.
+ -->
+ <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+ 	<parent>
+ 		<artifactId>MetaModel-mongodb</artifactId>
+ 		<groupId>org.apache.metamodel</groupId>
 -		<version>4.5.3-SNAPSHOT</version>
++		<version>5.0-SNAPSHOT</version>
+ 	</parent>
+ 	<modelVersion>4.0.0</modelVersion>
+ 	<artifactId>MetaModel-mongodb-mongo3</artifactId>
+ 	<name>MetaModel module for MongoDB 3.x</name>
+ 	<dependencies>
+ 		<dependency>
+ 			<groupId>org.apache.metamodel</groupId>
+ 			<artifactId>MetaModel-core</artifactId>
+ 			<version>${project.version}</version>
+ 		</dependency>
+ 		<dependency>
+             <groupId>org.apache.metamodel</groupId>
+             <artifactId>MetaModel-mongodb-common</artifactId>
+             <version>${project.version}</version>
+         </dependency>
+ 		<dependency>
+ 			<groupId>org.mongodb</groupId>
+ 			<artifactId>mongo-java-driver</artifactId>
+ 			<version>3.1.0</version>
+ 		</dependency>
+ 
+ 		<!-- Test dependencies -->
+ 		<dependency>
+ 			<groupId>org.apache.metamodel</groupId>
+ 			<artifactId>MetaModel-jdbc</artifactId>
+ 			<version>${project.version}</version>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>org.apache.derby</groupId>
+ 			<artifactId>derby</artifactId>
+ 			<version>10.8.1.2</version>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>org.slf4j</groupId>
+ 			<artifactId>slf4j-nop</artifactId>
+ 			<scope>test</scope>
+ 		</dependency>
+ 		<dependency>
+ 			<groupId>junit</groupId>
+ 			<artifactId>junit</artifactId>
+ 			<scope>test</scope>
+ 		</dependency>
+ 	</dependencies>
+ </project>

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/mongodb/mongo3/src/main/java/org/apache/metamodel/mongodb/mongo3/MongoDbDataContext.java
----------------------------------------------------------------------
diff --cc mongodb/mongo3/src/main/java/org/apache/metamodel/mongodb/mongo3/MongoDbDataContext.java
index 0000000,fbc9047..cf89f39
mode 000000,100644..100644
--- a/mongodb/mongo3/src/main/java/org/apache/metamodel/mongodb/mongo3/MongoDbDataContext.java
+++ b/mongodb/mongo3/src/main/java/org/apache/metamodel/mongodb/mongo3/MongoDbDataContext.java
@@@ -1,0 -1,545 +1,547 @@@
+ /**
+  * 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.metamodel.mongodb.mongo3;
+ 
+ import java.util.ArrayList;
+ import java.util.Arrays;
+ import java.util.HashSet;
+ import java.util.List;
+ import java.util.Map.Entry;
+ import java.util.Set;
+ import java.util.SortedMap;
+ import java.util.TreeMap;
+ import java.util.regex.Pattern;
+ 
+ import org.apache.metamodel.DataContext;
+ import org.apache.metamodel.MetaModelException;
+ import org.apache.metamodel.QueryPostprocessDataContext;
+ import org.apache.metamodel.UpdateScript;
++import org.apache.metamodel.UpdateSummary;
+ import org.apache.metamodel.UpdateableDataContext;
+ import org.apache.metamodel.data.DataSet;
+ import org.apache.metamodel.data.DataSetHeader;
+ import org.apache.metamodel.data.InMemoryDataSet;
+ import org.apache.metamodel.data.Row;
+ import org.apache.metamodel.data.SimpleDataSetHeader;
+ import org.apache.metamodel.mongodb.common.MongoDBUtils;
+ import org.apache.metamodel.query.FilterItem;
+ import org.apache.metamodel.query.FromItem;
+ import org.apache.metamodel.query.OperatorType;
+ import org.apache.metamodel.query.Query;
+ import org.apache.metamodel.query.SelectItem;
+ import org.apache.metamodel.schema.Column;
+ import org.apache.metamodel.schema.ColumnType;
+ import org.apache.metamodel.schema.ColumnTypeImpl;
+ import org.apache.metamodel.schema.MutableColumn;
+ import org.apache.metamodel.schema.MutableSchema;
+ import org.apache.metamodel.schema.MutableTable;
+ import org.apache.metamodel.schema.Schema;
+ import org.apache.metamodel.schema.Table;
+ import org.apache.metamodel.util.SimpleTableDef;
+ import org.bson.Document;
+ import org.bson.types.ObjectId;
+ import org.slf4j.Logger;
+ import org.slf4j.LoggerFactory;
+ 
+ import com.mongodb.DB;
+ import com.mongodb.WriteConcern;
+ import com.mongodb.client.FindIterable;
+ import com.mongodb.client.MongoCollection;
+ import com.mongodb.client.MongoCursor;
+ import com.mongodb.client.MongoDatabase;
+ import com.mongodb.client.MongoIterable;
+ 
+ /**
+  * DataContext implementation for MongoDB.
+  *
+  * Since MongoDB has no schema, a virtual schema will be used in this
+  * DataContext. This implementation supports either automatic discovery of a
+  * schema or manual specification of a schema, through the
+  * {@link SimpleTableDef} class.
+  */
+ public class MongoDbDataContext extends QueryPostprocessDataContext implements UpdateableDataContext {
+ 
+     private static final Logger logger = LoggerFactory.getLogger(MongoDbDataSet.class);
+ 
+     private final MongoDatabase _mongoDb;
+     private final SimpleTableDef[] _tableDefs;
+     private WriteConcernAdvisor _writeConcernAdvisor;
+     private Schema _schema;
+ 
+     /**
+      * Constructs a {@link MongoDbDataContext}. This constructor accepts a
+      * custom array of {@link SimpleTableDef}s which allows the user to define
+      * his own view on the collections in the database.
+      *
+      * @param mongoDb
+      *            the mongo db connection
+      * @param tableDefs
+      *            an array of {@link SimpleTableDef}s, which define the table
+      *            and column model of the mongo db collections. (consider using
+      *            {@link #detectSchema(MongoDatabase)} or {@link #detectTable(MongoDatabase, String)}
+      *            ).
+      */
+     public MongoDbDataContext(MongoDatabase mongoDb, SimpleTableDef... tableDefs) {
+         _mongoDb = mongoDb;
+         _tableDefs = tableDefs;
+         _schema = null;
+     }
+ 
+     /**
+      * Constructs a {@link MongoDbDataContext} and automatically detects the
+      * schema structure/view on all collections (see {@link #detectSchema(MongoDatabase)}).
+      *
+      * @param mongoDb
+      *            the mongo db connection
+      */
+     public MongoDbDataContext(MongoDatabase mongoDb) {
+         this(mongoDb, detectSchema(mongoDb));
+     }
+ 
+     /**
+      * Performs an analysis of the available collections in a Mongo {@link DB}
+      * instance and tries to detect the table's structure based on the first
+      * 1000 documents in each collection.
+      *
+      * @param mongoDb
+      *            the mongo db to inspect
+      * @return a mutable schema instance, useful for further fine tuning by the
+      *         user.
+      * @see #detectTable(MongoDatabase, String)
+      */
+     public static SimpleTableDef[] detectSchema(MongoDatabase mongoDb) {
+         MongoIterable<String> collectionNames = mongoDb.listCollectionNames();
+         List<SimpleTableDef> result = new ArrayList<>();
+ 
+         for (String collectionName : collectionNames) {
+             SimpleTableDef table = detectTable(mongoDb, collectionName);
+             result.add(table);
+         }
+         return result.toArray(new SimpleTableDef[0]);
+     }
+ 
+     /**
+      * Performs an analysis of an available collection in a Mongo {@link DB}
+      * instance and tries to detect the table structure based on the first 1000
+      * documents in the collection.
+      *
+      * @param mongoDb
+      *            the mongo DB
+      * @param collectionName
+      *            the name of the collection
+      * @return a table definition for mongo db.
+      */
+     public static SimpleTableDef detectTable(MongoDatabase mongoDb, String collectionName) {
+         
+         final MongoCollection<Document> collection = mongoDb.getCollection(collectionName);
+         final FindIterable<Document> iterable = collection.find().limit(1000);
+ 
+         final SortedMap<String, Set<Class<?>>> columnsAndTypes = new TreeMap<String, Set<Class<?>>>();
+         for (Document document : iterable) {
+             Set<String> keysInObject = document.keySet();
+             for (String key : keysInObject) {
+                 Set<Class<?>> types = columnsAndTypes.get(key);
+                 if (types == null) {
+                     types = new HashSet<Class<?>>();
+                     columnsAndTypes.put(key, types);
+                 }
+                 Object value = document.get(key);
+                 if (value != null) {
+                     types.add(value.getClass());
+                 }
+             }
+         }
+            
+         final String[] columnNames = new String[columnsAndTypes.size()];
+         final ColumnType[] columnTypes = new ColumnType[columnsAndTypes.size()];
+ 
+         int i = 0;
+         for (Entry<String, Set<Class<?>>> columnAndTypes : columnsAndTypes.entrySet()) {
+             final String columnName = columnAndTypes.getKey();
+             final Set<Class<?>> columnTypeSet = columnAndTypes.getValue();
+             final Class<?> columnType;
+             if (columnTypeSet.size() == 1) {
+                 columnType = columnTypeSet.iterator().next();
+             } else {
+                 columnType = Object.class;
+             }
+             columnNames[i] = columnName;
+             if (columnType == ObjectId.class) {
+                 columnTypes[i] = ColumnType.ROWID;
+             } else {
+                 columnTypes[i] = ColumnTypeImpl.convertColumnType(columnType);
+             }
+             i++;
+         }
+ 
+         return new SimpleTableDef(collectionName, columnNames, columnTypes);
+     }
+ 
+     @Override
+     protected Schema getMainSchema() throws MetaModelException {
+         if (_schema == null) {
+             MutableSchema schema = new MutableSchema(getMainSchemaName());
+             for (SimpleTableDef tableDef : _tableDefs) {
+ 
+                 MutableTable table = tableDef.toTable().setSchema(schema);
+                 Column[] rowIdColumns = table.getColumnsOfType(ColumnType.ROWID);
+                 for (Column column : rowIdColumns) {
+                     if (column instanceof MutableColumn) {
+                         ((MutableColumn) column).setPrimaryKey(true);
+                     }
+                 }
+ 
+                 schema.addTable(table);
+             }
+ 
+             _schema = schema;
+         }
+         return _schema;
+     }
+ 
+     @Override
+     protected String getMainSchemaName() throws MetaModelException {
+         return _mongoDb.getName();
+     }
+ 
+     @Override
+     protected Number executeCountQuery(Table table, List<FilterItem> whereItems, boolean functionApproximationAllowed) {
+         final MongoCollection<Document> collection = _mongoDb.getCollection(table.getName());
+ 
+         final Document query = createMongoDbQuery(table, whereItems);
+ 
+         logger.info("Executing MongoDB 'count' query: {}", query);
+         final long count = collection.count(query);
+ 
+         return count;
+     }
+ 
+     @Override
+     protected Row executePrimaryKeyLookupQuery(Table table, List<SelectItem> selectItems, Column primaryKeyColumn,
+             Object keyValue) {
+         final MongoCollection<Document> collection = _mongoDb.getCollection(table.getName());
+ 
+         List<FilterItem> whereItems = new ArrayList<FilterItem>();
+         SelectItem selectItem = new SelectItem(primaryKeyColumn);
+         FilterItem primaryKeyWhereItem = new FilterItem(selectItem, OperatorType.EQUALS_TO, keyValue);
+         whereItems.add(primaryKeyWhereItem);
+         final Document query = createMongoDbQuery(table, whereItems);
+         final Document resultDoc = collection.find(query).first();
+ 
+         DataSetHeader header = new SimpleDataSetHeader(selectItems);
+ 
+         Row row = MongoDBUtils.toRow(resultDoc, header);
+ 
+         return row;
+     }
+ 
+     @Override
+     public DataSet executeQuery(Query query) {
+         // Check for queries containing only simple selects and where clauses,
+         // or if it is a COUNT(*) query.
+ 
+         // if from clause only contains a main schema table
+         List<FromItem> fromItems = query.getFromClause().getItems();
+         if (fromItems.size() == 1 && fromItems.get(0).getTable() != null
+                 && fromItems.get(0).getTable().getSchema() == _schema) {
+             final Table table = fromItems.get(0).getTable();
+ 
+             // if GROUP BY, HAVING and ORDER BY clauses are not specified
+             if (query.getGroupByClause().isEmpty() && query.getHavingClause().isEmpty()
+                     && query.getOrderByClause().isEmpty()) {
+ 
+                 final List<FilterItem> whereItems = query.getWhereClause().getItems();
+ 
+                 // if all of the select items are "pure" column selection
+                 boolean allSelectItemsAreColumns = true;
+                 List<SelectItem> selectItems = query.getSelectClause().getItems();
+ 
+                 // if it is a
+                 // "SELECT [columns] FROM [table] WHERE [conditions]"
+                 // query.
+                 for (SelectItem selectItem : selectItems) {
+                     if (selectItem.getFunction() != null || selectItem.getColumn() == null) {
+                         allSelectItemsAreColumns = false;
+                         break;
+                     }
+                 }
+ 
+                 if (allSelectItemsAreColumns) {
+                     logger.debug("Query can be expressed in full MongoDB, no post processing needed.");
+ 
+                     // prepare for a non-post-processed query
+                     Column[] columns = new Column[selectItems.size()];
+                     for (int i = 0; i < columns.length; i++) {
+                         columns[i] = selectItems.get(i).getColumn();
+                     }
+ 
+                     // checking if the query is a primary key lookup query
+                     if (whereItems.size() == 1) {
+                         final FilterItem whereItem = whereItems.get(0);
+                         final SelectItem selectItem = whereItem.getSelectItem();
+                         if (!whereItem.isCompoundFilter() && selectItem != null && selectItem.getColumn() != null) {
+                             final Column column = selectItem.getColumn();
+                             if (column.isPrimaryKey() && OperatorType.EQUALS_TO.equals(whereItem.getOperator())) {
+                                 logger.debug("Query is a primary key lookup query. Trying executePrimaryKeyLookupQuery(...)");
+                                 final Object operand = whereItem.getOperand();
+                                 final Row row = executePrimaryKeyLookupQuery(table, selectItems, column, operand);
+                                 if (row == null) {
+                                     logger.debug("DataContext did not return any primary key lookup query results. Proceeding "
+                                             + "with manual lookup.");
+                                 } else {
+                                     final DataSetHeader header = new SimpleDataSetHeader(selectItems);
+                                     return new InMemoryDataSet(header, row);
+                                 }
+                             }
+                         }
+                     }
+ 
+                     int firstRow = (query.getFirstRow() == null ? 1 : query.getFirstRow());
+                     int maxRows = (query.getMaxRows() == null ? -1 : query.getMaxRows());
+ 
+                     final DataSet dataSet = materializeMainSchemaTableInternal(table, columns, whereItems, firstRow,
+                             maxRows, false);
+                     return dataSet;
+                 }
+             }
+         }
+ 
+         logger.debug("Query will be simplified for MongoDB and post processed.");
+         return super.executeQuery(query);
+     }
+ 
+     private DataSet materializeMainSchemaTableInternal(Table table, Column[] columns, List<FilterItem> whereItems,
+             int firstRow, int maxRows, boolean queryPostProcessed) {
+         final MongoCollection<Document> collection = _mongoDb.getCollection(table.getName());
+ 
+         final Document query = createMongoDbQuery(table, whereItems);
+ 
+         logger.info("Executing MongoDB 'find' query: {}", query);
+         FindIterable<Document> iterable = collection.find(query);
+ 
+         if (maxRows > 0) {
+             iterable = iterable.limit(maxRows);
+         }
+         if (firstRow > 1) {
+             final int skip = firstRow - 1;
+             iterable = iterable.skip(skip);
+         }
+ 
+         MongoCursor<Document> cursor = iterable.iterator();
+ 
+         return new MongoDbDataSet(cursor, columns, queryPostProcessed);
+     }
+ 
+     protected Document createMongoDbQuery(Table table, List<FilterItem> whereItems) {
+         assert _schema == table.getSchema();
+ 
+         final Document query = new Document();
+         if (whereItems != null && !whereItems.isEmpty()) {
+             for (FilterItem item : whereItems) {
+                 convertToCursorObject(query, item);
+             }
+         }
+ 
+         return query;
+     }
+ 
+     private static Object convertArrayToList(Object arr) {
+         if (arr instanceof boolean[]) {
+             return Arrays.asList((boolean[])arr);
+         } else if (arr instanceof byte[]) {
+             return Arrays.asList((byte[])arr);
+         } else if (arr instanceof short[]) {
+             return Arrays.asList((short[])arr);
+         } else if (arr instanceof char[]) {
+             return Arrays.asList((char[])arr);
+         } else if (arr instanceof int[]) {
+             return Arrays.asList((int[])arr);
+         } else if (arr instanceof long[]) {
+             return Arrays.asList((long[])arr);
+         } else if (arr instanceof float[]) {
+             return Arrays.asList((float[])arr);
+         } else if (arr instanceof double[]) {
+             return Arrays.asList((double[])arr);
+         } else if (arr instanceof Object[]) {
+             return Arrays.asList((Object[])arr);
+         }
+         // It's not an array.
+         return null;
+     }
+     
+     private void convertToCursorObject(Document query, FilterItem item) {
+         if (item.isCompoundFilter()) {
+ 
+             List<Document> orList = new ArrayList<Document>();
+ 
+             final FilterItem[] childItems = item.getChildItems();
+             for (FilterItem childItem : childItems) {
+                 Document childDoc = new Document();
+                 convertToCursorObject(childDoc, childItem);
+                 orList.add(childDoc);
+             }
+ 
+             query.put("$or", orList);
+ 
+         } else {
+ 
+             final Column column = item.getSelectItem().getColumn();
+             final String columnName = column.getName();
+             final String operatorName = getOperatorName(item);
+ 
+             Object operand = item.getOperand();
+             if (ObjectId.isValid(String.valueOf(operand))) {
+                 operand = new ObjectId(String.valueOf(operand));
+             } else if (operand != null && operand.getClass().isArray()){
+                 operand = convertArrayToList(operand);
+             }
+ 
+             final Document existingFilterObject = (Document) query.get(columnName);
+             if (existingFilterObject == null) {
+                 if (operatorName == null) {
+                     if (OperatorType.LIKE.equals(item.getOperator())) {
+                         query.put(columnName, turnOperandIntoRegExp(operand));
+                     } else {
+                         query.put(columnName, operand);
+                     }
+                 } else {
+                     query.put(columnName, new Document(operatorName, operand));
+                 }
+             } else {
+                 if (operatorName == null) {
+                     throw new IllegalStateException("Cannot retrieve records for a column with two EQUALS_TO operators");
+                 } else {
+                     existingFilterObject.append(operatorName, operand);
+                 }
+             }
+         }
+     }
+ 
+     private String getOperatorName(FilterItem item) {
+         final OperatorType operator = item.getOperator();
+ 
+         if (OperatorType.EQUALS_TO.equals(operator)) {
+             return null;
+         }
+         if (OperatorType.LIKE.equals(operator)) {
+             return null;
+         }
+         if (OperatorType.LESS_THAN.equals(operator)) {
+             return "$lt";
+         }
+         if (OperatorType.LESS_THAN_OR_EQUAL.equals(operator)) {
+             return "$lte";
+         }
+         if (OperatorType.GREATER_THAN.equals(operator)) {
+             return "$gt";
+         }
+         if (OperatorType.GREATER_THAN_OR_EQUAL.equals(operator)) {
+             return "$gte";
+         }
+         if (OperatorType.DIFFERENT_FROM.equals(operator)) {
+             return "$ne";
+         }
+         if (OperatorType.IN.equals(operator)) {
+             return "$in";
+         }
+ 
+         throw new IllegalStateException("Unsupported operator type: " + operator);
+     }
+ 
+     private Pattern turnOperandIntoRegExp(Object operand) {
+         StringBuilder operandAsRegExp = new StringBuilder(replaceWildCardLikeChars(operand.toString()));
+         operandAsRegExp.insert(0, "^").append("$");
+         return Pattern.compile(operandAsRegExp.toString(), Pattern.CASE_INSENSITIVE);
+     }
+ 
+     private String replaceWildCardLikeChars(String operand) {
+         return operand.replaceAll("%", ".*");
+     }
+ 
+     @Override
+     protected DataSet materializeMainSchemaTable(Table table, Column[] columns, int maxRows) {
+         return materializeMainSchemaTableInternal(table, columns, null, 1, maxRows, true);
+     }
+ 
+     @Override
+     protected DataSet materializeMainSchemaTable(Table table, Column[] columns, int firstRow, int maxRows) {
+         return materializeMainSchemaTableInternal(table, columns, null, firstRow, maxRows, true);
+     }
+ 
+     /**
+      * Executes an update with a specific {@link WriteConcernAdvisor}.
+      */
 -    public void executeUpdate(UpdateScript update, WriteConcernAdvisor writeConcernAdvisor) {
++    public UpdateSummary executeUpdate(UpdateScript update, WriteConcernAdvisor writeConcernAdvisor) {
+         MongoDbUpdateCallback callback = new MongoDbUpdateCallback(this, writeConcernAdvisor);
+         try {
+             update.run(callback);
+         } finally {
+             callback.close();
+         }
++        return callback.getUpdateSummary();
+     }
+ 
+     /**
+      * Executes an update with a specific {@link WriteConcern}.
+      */
 -    public void executeUpdate(UpdateScript update, WriteConcern writeConcern) {
 -        executeUpdate(update, new SimpleWriteConcernAdvisor(writeConcern));
++    public UpdateSummary executeUpdate(UpdateScript update, WriteConcern writeConcern) {
++        return executeUpdate(update, new SimpleWriteConcernAdvisor(writeConcern));
+     }
+ 
+     @Override
 -    public void executeUpdate(UpdateScript update) {
 -        executeUpdate(update, getWriteConcernAdvisor());
++    public UpdateSummary executeUpdate(UpdateScript update) {
++        return executeUpdate(update, getWriteConcernAdvisor());
+     }
+ 
+     /**
+      * Gets the {@link WriteConcernAdvisor} to use on
+      * {@link #executeUpdate(UpdateScript)} calls.
+      */
+     public WriteConcernAdvisor getWriteConcernAdvisor() {
+         if (_writeConcernAdvisor == null) {
+             return new DefaultWriteConcernAdvisor();
+         }
+         return _writeConcernAdvisor;
+     }
+ 
+     /**
+      * Sets a global {@link WriteConcern} advisor to use on
+      * {@link #executeUpdate(UpdateScript)}.
+      */
+     public void setWriteConcernAdvisor(WriteConcernAdvisor writeConcernAdvisor) {
+         _writeConcernAdvisor = writeConcernAdvisor;
+     }
+ 
+     /**
+      * Gets the {@link DB} instance that this {@link DataContext} is backed by.
+      * @return 
+      */
+     public MongoDatabase getMongoDb() {
+         return _mongoDb;
+     }
+ 
+     protected void addTable(MutableTable table) {
+         if (_schema instanceof MutableSchema) {
+             MutableSchema mutableSchema = (MutableSchema) _schema;
+             mutableSchema.addTable(table);
+         } else {
+             throw new UnsupportedOperationException("Schema is not mutable");
+         }
+     }
+ }

http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/mongodb/pom.xml
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http://git-wip-us.apache.org/repos/asf/metamodel/blob/6d50f0e3/pom.xml
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