package org.apache.lucene.index;
/**
* 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 org.apache.lucene.store.Directory;
import org.apache.lucene.store.IndexOutput;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.StringHelper;
import java.io.IOException;
final class TermVectorsWriter {
private IndexOutput tvx = null, tvd = null, tvf = null;
private FieldInfos fieldInfos;
public TermVectorsWriter(Directory directory, String segment,
FieldInfos fieldInfos)
throws IOException {
// Open files for TermVector storage
tvx = directory.createOutput(IndexFileNames.segmentFileName(segment, "", IndexFileNames.VECTORS_INDEX_EXTENSION));
tvx.writeInt(TermVectorsReader.FORMAT_CURRENT);
tvd = directory.createOutput(IndexFileNames.segmentFileName(segment, "", IndexFileNames.VECTORS_DOCUMENTS_EXTENSION));
tvd.writeInt(TermVectorsReader.FORMAT_CURRENT);
tvf = directory.createOutput(IndexFileNames.segmentFileName(segment, "", IndexFileNames.VECTORS_FIELDS_EXTENSION));
tvf.writeInt(TermVectorsReader.FORMAT_CURRENT);
this.fieldInfos = fieldInfos;
}
/**
* Add a complete document specified by all its term vectors. If document has no
* term vectors, add value for tvx.
*
* @param vectors
* @throws IOException
*/
public final void addAllDocVectors(TermFreqVector[] vectors)
throws IOException {
tvx.writeLong(tvd.getFilePointer());
tvx.writeLong(tvf.getFilePointer());
if (vectors != null) {
final int numFields = vectors.length;
tvd.writeVInt(numFields);
long[] fieldPointers = new long[numFields];
for (int i=0; i<numFields; i++) {
fieldPointers[i] = tvf.getFilePointer();
final int fieldNumber = fieldInfos.fieldNumber(vectors[i].getField());
// 1st pass: write field numbers to tvd
tvd.writeVInt(fieldNumber);
final int numTerms = vectors[i].size();
tvf.writeVInt(numTerms);
final TermPositionVector tpVector;
final byte bits;
final boolean storePositions;
final boolean storeOffsets;
if (vectors[i] instanceof TermPositionVector) {
// May have positions & offsets
tpVector = (TermPositionVector) vectors[i];
storePositions = tpVector.size() > 0 && tpVector.getTermPositions(0) != null;
storeOffsets = tpVector.size() > 0 && tpVector.getOffsets(0) != null;
bits = (byte) ((storePositions ? TermVectorsReader.STORE_POSITIONS_WITH_TERMVECTOR : 0) +
(storeOffsets ? TermVectorsReader.STORE_OFFSET_WITH_TERMVECTOR : 0));
} else {
tpVector = null;
bits = 0;
storePositions = false;
storeOffsets = false;
}
tvf.writeVInt(bits);
final BytesRef[] terms = vectors[i].getTerms();
final int[] freqs = vectors[i].getTermFrequencies();
for (int j=0; j<numTerms; j++) {
int start = j == 0 ? 0 : StringHelper.bytesDifference(terms[j-1].bytes,
terms[j-1].length,
terms[j].bytes,
terms[j].length);
int length = terms[j].length - start;
tvf.writeVInt(start); // write shared prefix length
tvf.writeVInt(length); // write delta length
tvf.writeBytes(terms[j].bytes, start, length); // write delta bytes
final int termFreq = freqs[j];
tvf.writeVInt(termFreq);
if (storePositions) {
final int[] positions = tpVector.getTermPositions(j);
if (positions == null)
throw new IllegalStateException("Trying to write positions that are null!");
assert positions.length == termFreq;
// use delta encoding for positions
int lastPosition = 0;
for(int k=0;k<positions.length;k++) {
final int position = positions[k];
tvf.writeVInt(position-lastPosition);
lastPosition = position;
}
}
if (storeOffsets) {
final TermVectorOffsetInfo[] offsets = tpVector.getOffsets(j);
if (offsets == null)
throw new IllegalStateException("Trying to write offsets that are null!");
assert offsets.length == termFreq;
// use delta encoding for offsets
int lastEndOffset = 0;
for(int k=0;k<offsets.length;k++) {
final int startOffset = offsets[k].getStartOffset();
final int endOffset = offsets[k].getEndOffset();
tvf.writeVInt(startOffset-lastEndOffset);
tvf.writeVInt(endOffset-startOffset);
lastEndOffset = endOffset;
}
}
}
}
// 2nd pass: write field pointers to tvd
if (numFields > 1) {
long lastFieldPointer = fieldPointers[0];
for (int i=1; i<numFields; i++) {
final long fieldPointer = fieldPointers[i];
tvd.writeVLong(fieldPointer-lastFieldPointer);
lastFieldPointer = fieldPointer;
}
}
} else
tvd.writeVInt(0);
}
/**
* Do a bulk copy of numDocs documents from reader to our
* streams. This is used to expedite merging, if the
* field numbers are congruent.
*/
final void addRawDocuments(TermVectorsReader reader, int[] tvdLengths, int[] tvfLengths, int numDocs) throws IOException {
long tvdPosition = tvd.getFilePointer();
long tvfPosition = tvf.getFilePointer();
long tvdStart = tvdPosition;
long tvfStart = tvfPosition;
for(int i=0;i<numDocs;i++) {
tvx.writeLong(tvdPosition);
tvdPosition += tvdLengths[i];
tvx.writeLong(tvfPosition);
tvfPosition += tvfLengths[i];
}
tvd.copyBytes(reader.getTvdStream(), tvdPosition-tvdStart);
tvf.copyBytes(reader.getTvfStream(), tvfPosition-tvfStart);
assert tvd.getFilePointer() == tvdPosition;
assert tvf.getFilePointer() == tvfPosition;
}
/** Close all streams. */
final void close() throws IOException {
// make an effort to close all streams we can but remember and re-throw
// the first exception encountered in this process
IOException keep = null;
if (tvx != null)
try {
tvx.close();
} catch (IOException e) {
keep = e;
}
if (tvd != null)
try {
tvd.close();
} catch (IOException e) {
if (keep == null) keep = e;
}
if (tvf != null)
try {
tvf.close();
} catch (IOException e) {
if (keep == null) keep = e;
}
if (keep != null) throw (IOException) keep.fillInStackTrace();
}
}