org.apache.lucene.codecs.lucene50.Lucene50SegmentInfoFormat Maven / Gradle / Ivy
package org.apache.lucene.codecs.lucene50;
/*
* 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.
*/
import java.io.IOException;
import java.util.Collections;
import java.util.Map;
import java.util.Set;
import org.apache.lucene.codecs.CodecUtil;
import org.apache.lucene.codecs.SegmentInfoFormat;
import org.apache.lucene.index.CorruptIndexException;
import org.apache.lucene.index.IndexFileNames;
import org.apache.lucene.index.IndexWriter; // javadocs
import org.apache.lucene.index.SegmentInfo; // javadocs
import org.apache.lucene.index.SegmentInfos; // javadocs
import org.apache.lucene.store.ChecksumIndexInput;
import org.apache.lucene.store.DataOutput; // javadocs
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.IOContext;
import org.apache.lucene.store.IndexOutput;
import org.apache.lucene.util.Version;
/**
* Lucene 5.0 Segment info format.
*
* Files:
*
* - .si: Header, SegVersion, SegSize, IsCompoundFile, Diagnostics, Files, Attributes, Footer
*
* Data types:
*
* - Header --> {@link CodecUtil#writeIndexHeader IndexHeader}
* - SegSize --> {@link DataOutput#writeInt Int32}
* - SegVersion --> {@link DataOutput#writeString String}
* - Files --> {@link DataOutput#writeSetOfStrings Set<String>}
* - Diagnostics,Attributes --> {@link DataOutput#writeMapOfStrings Map<String,String>}
* - IsCompoundFile --> {@link DataOutput#writeByte Int8}
* - Footer --> {@link CodecUtil#writeFooter CodecFooter}
*
* Field Descriptions:
*
* - SegVersion is the code version that created the segment.
* - SegSize is the number of documents contained in the segment index.
* - IsCompoundFile records whether the segment is written as a compound file or
* not. If this is -1, the segment is not a compound file. If it is 1, the segment
* is a compound file.
* - The Diagnostics Map is privately written by {@link IndexWriter}, as a debugging aid,
* for each segment it creates. It includes metadata like the current Lucene
* version, OS, Java version, why the segment was created (merge, flush,
* addIndexes), etc.
* - Files is a list of files referred to by this segment.
*
*
* @see SegmentInfos
* @lucene.experimental
*/
public class Lucene50SegmentInfoFormat extends SegmentInfoFormat {
/** Sole constructor. */
public Lucene50SegmentInfoFormat() {
}
@Override
public SegmentInfo read(Directory dir, String segment, byte[] segmentID, IOContext context) throws IOException {
final String fileName = IndexFileNames.segmentFileName(segment, "", Lucene50SegmentInfoFormat.SI_EXTENSION);
try (ChecksumIndexInput input = dir.openChecksumInput(fileName, context)) {
Throwable priorE = null;
SegmentInfo si = null;
try {
int format = CodecUtil.checkIndexHeader(input, Lucene50SegmentInfoFormat.CODEC_NAME,
Lucene50SegmentInfoFormat.VERSION_START,
Lucene50SegmentInfoFormat.VERSION_CURRENT,
segmentID, "");
final Version version = Version.fromBits(input.readInt(), input.readInt(), input.readInt());
final int docCount = input.readInt();
if (docCount < 0) {
throw new CorruptIndexException("invalid docCount: " + docCount, input);
}
final boolean isCompoundFile = input.readByte() == SegmentInfo.YES;
final Map diagnostics;
final Set files;
final Map attributes;
if (format >= VERSION_SAFE_MAPS) {
diagnostics = input.readMapOfStrings();
files = input.readSetOfStrings();
attributes = input.readMapOfStrings();
} else {
diagnostics = Collections.unmodifiableMap(input.readStringStringMap());
files = Collections.unmodifiableSet(input.readStringSet());
attributes = Collections.unmodifiableMap(input.readStringStringMap());
}
si = new SegmentInfo(dir, version, segment, docCount, isCompoundFile, null, diagnostics, segmentID, attributes);
si.setFiles(files);
} catch (Throwable exception) {
priorE = exception;
} finally {
CodecUtil.checkFooter(input, priorE);
}
return si;
}
}
@Override
public void write(Directory dir, SegmentInfo si, IOContext ioContext) throws IOException {
final String fileName = IndexFileNames.segmentFileName(si.name, "", Lucene50SegmentInfoFormat.SI_EXTENSION);
try (IndexOutput output = dir.createOutput(fileName, ioContext)) {
// Only add the file once we've successfully created it, else IFD assert can trip:
si.addFile(fileName);
CodecUtil.writeIndexHeader(output,
Lucene50SegmentInfoFormat.CODEC_NAME,
Lucene50SegmentInfoFormat.VERSION_CURRENT,
si.getId(),
"");
Version version = si.getVersion();
if (version.major < 5) {
throw new IllegalArgumentException("invalid major version: should be >= 5 but got: " + version.major + " segment=" + si);
}
// Write the Lucene version that created this segment, since 3.1
output.writeInt(version.major);
output.writeInt(version.minor);
output.writeInt(version.bugfix);
assert version.prerelease == 0;
output.writeInt(si.maxDoc());
output.writeByte((byte) (si.getUseCompoundFile() ? SegmentInfo.YES : SegmentInfo.NO));
output.writeMapOfStrings(si.getDiagnostics());
Set files = si.files();
for (String file : files) {
if (!IndexFileNames.parseSegmentName(file).equals(si.name)) {
throw new IllegalArgumentException("invalid files: expected segment=" + si.name + ", got=" + files);
}
}
output.writeSetOfStrings(files);
output.writeMapOfStrings(si.getAttributes());
CodecUtil.writeFooter(output);
}
}
/** File extension used to store {@link SegmentInfo}. */
public final static String SI_EXTENSION = "si";
static final String CODEC_NAME = "Lucene50SegmentInfo";
static final int VERSION_START = 0;
static final int VERSION_SAFE_MAPS = 1;
static final int VERSION_CURRENT = VERSION_SAFE_MAPS;
}