/*
* 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.lucene.index;
import java.io.IOException;
import java.util.List;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.search.TermRangeQuery;
import org.apache.lucene.search.Weight;
import org.apache.lucene.store.Directory;
import org.apache.lucene.util.BitSetIterator;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.FixedBitSet;
import org.apache.lucene.util.IOUtils;
/**
* Split an index based on a {@link Query}.
*/
public class PKIndexSplitter {
private final Query docsInFirstIndex;
private final Directory input;
private final Directory dir1;
private final Directory dir2;
private final IndexWriterConfig config1;
private final IndexWriterConfig config2;
/**
* Split an index based on a {@link Query}. All documents that match the query
* are sent to dir1, remaining ones to dir2.
*/
public PKIndexSplitter(Directory input, Directory dir1, Directory dir2, Query docsInFirstIndex) {
this(input, dir1, dir2, docsInFirstIndex, newDefaultConfig(), newDefaultConfig());
}
private static IndexWriterConfig newDefaultConfig() {
return new IndexWriterConfig(null).setOpenMode(OpenMode.CREATE);
}
public PKIndexSplitter(Directory input, Directory dir1,
Directory dir2, Query docsInFirstIndex, IndexWriterConfig config1, IndexWriterConfig config2) {
this.input = input;
this.dir1 = dir1;
this.dir2 = dir2;
this.docsInFirstIndex = docsInFirstIndex;
this.config1 = config1;
this.config2 = config2;
}
/**
* Split an index based on a given primary key term
* and a 'middle' term. If the middle term is present, it's
* sent to dir2.
*/
public PKIndexSplitter(Directory input, Directory dir1, Directory dir2, Term midTerm) {
this(input, dir1, dir2,
new TermRangeQuery(midTerm.field(), null, midTerm.bytes(), true, false));
}
public PKIndexSplitter(Directory input, Directory dir1,
Directory dir2, Term midTerm, IndexWriterConfig config1, IndexWriterConfig config2) {
this(input, dir1, dir2,
new TermRangeQuery(midTerm.field(), null, midTerm.bytes(), true, false), config1, config2);
}
public void split() throws IOException {
boolean success = false;
DirectoryReader reader = DirectoryReader.open(input);
try {
// pass an individual config in here since one config can not be reused!
createIndex(config1, dir1, reader, docsInFirstIndex, false);
createIndex(config2, dir2, reader, docsInFirstIndex, true);
success = true;
} finally {
if (success) {
IOUtils.close(reader);
} else {
IOUtils.closeWhileHandlingException(reader);
}
}
}
private void createIndex(IndexWriterConfig config, Directory target, DirectoryReader reader, Query preserveFilter, boolean negateFilter) throws IOException {
boolean success = false;
final IndexWriter w = new IndexWriter(target, config);
try {
final IndexSearcher searcher = new IndexSearcher(reader);
searcher.setQueryCache(null);
final boolean needsScores = false; // scores are not needed, only matching docs
final Weight preserveWeight = searcher.createNormalizedWeight(preserveFilter, needsScores);
final List<LeafReaderContext> leaves = reader.leaves();
final CodecReader[] subReaders = new CodecReader[leaves.size()];
int i = 0;
for (final LeafReaderContext ctx : leaves) {
subReaders[i++] = new DocumentFilteredLeafIndexReader(ctx, preserveWeight, negateFilter);
}
w.addIndexes(subReaders);
success = true;
} finally {
if (success) {
w.close();
} else {
IOUtils.closeWhileHandlingException(w);
}
}
}
private static class DocumentFilteredLeafIndexReader extends FilterCodecReader {
final Bits liveDocs;
final int numDocs;
public DocumentFilteredLeafIndexReader(LeafReaderContext context, Weight preserveWeight, boolean negateFilter) throws IOException {
// our cast is ok, since we open the Directory.
super((CodecReader) context.reader());
final int maxDoc = in.maxDoc();
final FixedBitSet bits = new FixedBitSet(maxDoc);
// ignore livedocs here, as we filter them later:
final Scorer preverveScorer = preserveWeight.scorer(context);
if (preverveScorer != null) {
bits.or(preverveScorer.iterator());
}
if (negateFilter) {
bits.flip(0, maxDoc);
}
if (in.hasDeletions()) {
final Bits oldLiveDocs = in.getLiveDocs();
assert oldLiveDocs != null;
final DocIdSetIterator it = new BitSetIterator(bits, 0L); // the cost is not useful here
for (int i = it.nextDoc(); i != DocIdSetIterator.NO_MORE_DOCS; i = it.nextDoc()) {
if (!oldLiveDocs.get(i)) {
// we can safely modify the current bit, as the iterator already stepped over it:
bits.clear(i);
}
}
}
this.liveDocs = bits;
this.numDocs = bits.cardinality();
}
@Override
public int numDocs() {
return numDocs;
}
@Override
public Bits getLiveDocs() {
return liveDocs;
}
@Override
public CacheHelper getCoreCacheHelper() {
return in.getCoreCacheHelper();
}
@Override
public CacheHelper getReaderCacheHelper() {
return null;
}
}
}