svn commit: r1331781 - /lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40FieldInfosFormat.java

[rm...@apache.org]

Author: rmuir
Date: Sat Apr 28 15:03:21 2012
New Revision: 1331781

URL: http://svn.apache.org/viewvc?rev=1331781&view=rev
Log:
LUCENE-2946: doc 4.0 fieldinfos format

Modified:
    lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40FieldInfosFormat.java

Modified: lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40FieldInfosFormat.java
URL: http://svn.apache.org/viewvc/lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40FieldInfosFormat.java?rev=1331781&r1=1331780&r2=1331781&view=diff
==============================================================================
--- lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40FieldInfosFormat.java (original)
+++ lucene/dev/trunk/lucene/core/src/java/org/apache/lucene/codecs/lucene40/Lucene40FieldInfosFormat.java Sat Apr 28 15:03:21 2012
@@ -23,9 +23,75 @@ import java.util.Set;
 import org.apache.lucene.codecs.FieldInfosFormat;
 import org.apache.lucene.codecs.FieldInfosReader;
 import org.apache.lucene.codecs.FieldInfosWriter;
+import org.apache.lucene.index.DocValues; // javadoc
+import org.apache.lucene.index.DocValues.Type; // javadoc
 import org.apache.lucene.index.SegmentInfo;
+import org.apache.lucene.store.DataOutput; // javadoc
 
 /**
+ * Lucene 4.0 Field Infos format.
+ * <p>
+ * <p>Field names are stored in the field info file, with suffix <tt>.fnm</tt>.</p>
+ * <p>FieldInfos (.fnm) --&gt; FNMVersion,FieldsCount, &lt;FieldName,FieldNumber,
+ * FieldBits,DocValuesBits&gt; <sup>FieldsCount</sup></p>
+ * <p>Data types:
+ * <ul>
+ *   <li>FNMVersion, FieldsCount --&gt; {@link DataOutput#writeVInt VInt}</li>
+ *   <li>FieldName --&gt; {@link DataOutput#writeString String}</li>
+ *   <li>FieldBits, DocValuesBits --&gt; {@link DataOutput#writeByte Byte}</li>
+ *   <li>FieldNumber --&gt; {@link DataOutput#writeInt Uint32}</li>
+ * </ul>
+ * </p>
+ * Field Descriptions:
+ * <ul>
+ *   <li>FNMVersion is <code>Lucene40FieldInfosWriter.FORMAT_CURRENT</code>.</li>
+ *   <li>FieldsCount: the number of fields in this file.</li>
+ *   <li>FieldName: name of the field as a UTF-8 String.</li>
+ *   <li>FieldNumber: the field's number. Note that unlike previous versions of
+ *       Lucene, the fields are not numbered implicitly by their order in the
+ *       file, instead explicitly.</li>
+ *   <li>FieldBits: a byte containing field options.
+ *       <ul>
+ *         <li>The low-order bit is one for indexed fields, and zero for non-indexed
+ *             fields.</li>
+ *         <li>The second lowest-order bit is one for fields that have term vectors
+ *             stored, and zero for fields without term vectors.</li>
+ *         <li>If the third lowest order-bit is set (0x4), offsets are stored into
+ *             the postings list in addition to positions.</li>
+ *         <li>Fourth bit is unused.</li>
+ *         <li>If the fifth lowest-order bit is set (0x10), norms are omitted for the
+ *             indexed field.</li>
+ *         <li>If the sixth lowest-order bit is set (0x20), payloads are stored for the
+ *             indexed field.</li>
+ *         <li>If the seventh lowest-order bit is set (0x40), term frequencies and
+ *             positions omitted for the indexed field.</li>
+ *         <li>If the eighth lowest-order bit is set (0x80), positions are omitted for the
+ *             indexed field.</li>
+ *       </ul>
+ *    </li>
+ *    <li>DocValuesBits: a byte containing per-document value types. The type
+ *        recorded as two four-bit integers, with the high-order bits representing
+ *        <code>norms</code> options, and the low-order bits representing 
+ *        {@link DocValues} options. Each four-bit integer can be decoded as such:
+ *        <ul>
+ *          <li>0: no DocValues for this field.</li>
+ *          <li>1: variable-width signed integers. ({@link Type#VAR_INTS VAR_INTS})</li>
+ *          <li>2: 32-bit floating point values. ({@link Type#FLOAT_32 FLOAT_32})</li>
+ *          <li>3: 64-bit floating point values. ({@link Type#FLOAT_64 FLOAT_64})</li>
+ *          <li>4: fixed-length byte array values. ({@link Type#BYTES_FIXED_STRAIGHT BYTES_FIXED_STRAIGHT})</li>
+ *          <li>5: fixed-length dereferenced byte array values. ({@link Type#BYTES_FIXED_DEREF BYTES_FIXED_DEREF})</li>
+ *          <li>6: variable-length byte array values. ({@link Type#BYTES_VAR_STRAIGHT BYTES_VAR_STRAIGHT})</li>
+ *          <li>7: variable-length dereferenced byte array values. ({@link Type#BYTES_VAR_DEREF BYTES_VAR_DEREF})</li>
+ *          <li>8: 16-bit signed integers. ({@link Type#FIXED_INTS_16 FIXED_INTS_16})</li>
+ *          <li>9: 32-bit signed integers. ({@link Type#FIXED_INTS_32 FIXED_INTS_32})</li>
+ *          <li>10: 64-bit signed integers. ({@link Type#FIXED_INTS_64 FIXED_INTS_64})</li>
+ *          <li>11: 8-bit signed integers. ({@link Type#FIXED_INTS_8 FIXED_INTS_8})</li>
+ *          <li>12: fixed-length sorted byte array values. ({@link Type#BYTES_FIXED_SORTED BYTES_FIXED_SORTED})</li>
+ *          <li>13: variable-length sorted byte array values. ({@link Type#BYTES_VAR_SORTED BYTES_VAR_SORTED})</li>
+ *        </ul>
+ *    </li>
+ * </ul>
+ *
  * @lucene.experimental
  */
 public class Lucene40FieldInfosFormat extends FieldInfosFormat {