package org.apache.lucene.codecs.simpletext;
/*
* 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.BitSet;
import java.util.Collection;
import org.apache.lucene.codecs.LiveDocsFormat;
import org.apache.lucene.index.IndexFileNames;
import org.apache.lucene.index.SegmentCommitInfo;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.IOContext;
import org.apache.lucene.store.IndexInput;
import org.apache.lucene.store.IndexOutput;
import org.apache.lucene.util.ArrayUtil;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.CharsRef;
import org.apache.lucene.util.IOUtils;
import org.apache.lucene.util.MutableBits;
import org.apache.lucene.util.StringHelper;
import org.apache.lucene.util.UnicodeUtil;
/**
* reads/writes plaintext live docs
* <p>
* <b><font color="red">FOR RECREATIONAL USE ONLY</font></B>
* @lucene.experimental
*/
public class SimpleTextLiveDocsFormat extends LiveDocsFormat {
static final String LIVEDOCS_EXTENSION = "liv";
final static BytesRef SIZE = new BytesRef("size ");
final static BytesRef DOC = new BytesRef(" doc ");
final static BytesRef END = new BytesRef("END");
@Override
public MutableBits newLiveDocs(int size) throws IOException {
return new SimpleTextMutableBits(size);
}
@Override
public MutableBits newLiveDocs(Bits existing) throws IOException {
final SimpleTextBits bits = (SimpleTextBits) existing;
return new SimpleTextMutableBits((BitSet)bits.bits.clone(), bits.size);
}
@Override
public Bits readLiveDocs(Directory dir, SegmentCommitInfo info, IOContext context) throws IOException {
assert info.hasDeletions();
BytesRef scratch = new BytesRef();
CharsRef scratchUTF16 = new CharsRef();
String fileName = IndexFileNames.fileNameFromGeneration(info.info.name, LIVEDOCS_EXTENSION, info.getDelGen());
IndexInput in = null;
boolean success = false;
try {
in = dir.openInput(fileName, context);
SimpleTextUtil.readLine(in, scratch);
assert StringHelper.startsWith(scratch, SIZE);
int size = parseIntAt(scratch, SIZE.length, scratchUTF16);
BitSet bits = new BitSet(size);
SimpleTextUtil.readLine(in, scratch);
while (!scratch.equals(END)) {
assert StringHelper.startsWith(scratch, DOC);
int docid = parseIntAt(scratch, DOC.length, scratchUTF16);
bits.set(docid);
SimpleTextUtil.readLine(in, scratch);
}
success = true;
return new SimpleTextBits(bits, size);
} finally {
if (success) {
IOUtils.close(in);
} else {
IOUtils.closeWhileHandlingException(in);
}
}
}
private int parseIntAt(BytesRef bytes, int offset, CharsRef scratch) {
UnicodeUtil.UTF8toUTF16(bytes.bytes, bytes.offset+offset, bytes.length-offset, scratch);
return ArrayUtil.parseInt(scratch.chars, 0, scratch.length);
}
@Override
public void writeLiveDocs(MutableBits bits, Directory dir, SegmentCommitInfo info, int newDelCount, IOContext context) throws IOException {
BitSet set = ((SimpleTextBits) bits).bits;
int size = bits.length();
BytesRef scratch = new BytesRef();
String fileName = IndexFileNames.fileNameFromGeneration(info.info.name, LIVEDOCS_EXTENSION, info.getNextDelGen());
IndexOutput out = null;
boolean success = false;
try {
out = dir.createOutput(fileName, context);
SimpleTextUtil.write(out, SIZE);
SimpleTextUtil.write(out, Integer.toString(size), scratch);
SimpleTextUtil.writeNewline(out);
for (int i = set.nextSetBit(0); i >= 0; i=set.nextSetBit(i + 1)) {
SimpleTextUtil.write(out, DOC);
SimpleTextUtil.write(out, Integer.toString(i), scratch);
SimpleTextUtil.writeNewline(out);
}
SimpleTextUtil.write(out, END);
SimpleTextUtil.writeNewline(out);
success = true;
} finally {
if (success) {
IOUtils.close(out);
} else {
IOUtils.closeWhileHandlingException(out);
}
}
}
@Override
public void files(SegmentCommitInfo info, Collection<String> files) throws IOException {
if (info.hasDeletions()) {
files.add(IndexFileNames.fileNameFromGeneration(info.info.name, LIVEDOCS_EXTENSION, info.getDelGen()));
}
}
// read-only
static class SimpleTextBits implements Bits {
final BitSet bits;
final int size;
SimpleTextBits(BitSet bits, int size) {
this.bits = bits;
this.size = size;
}
@Override
public boolean get(int index) {
return bits.get(index);
}
@Override
public int length() {
return size;
}
}
// read-write
static class SimpleTextMutableBits extends SimpleTextBits implements MutableBits {
SimpleTextMutableBits(int size) {
this(new BitSet(size), size);
bits.set(0, size);
}
SimpleTextMutableBits(BitSet bits, int size) {
super(bits, size);
}
@Override
public void clear(int bit) {
bits.clear(bit);
}
}
}