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.util.Bits; import org.apache.lucene.util.ReaderUtil; import java.io.IOException; /** * Exposes flex API, merged from flex API of sub-segments. * * @lucene.experimental */ public final class MultiDocsEnum extends DocsEnum { private EnumWithSlice[] subs; int numSubs; int upto; DocsEnum current; int currentBase; Bits skipDocs; int doc = -1; MultiDocsEnum reset(final EnumWithSlice[] subs, final int numSubs) throws IOException { this.numSubs = numSubs; this.subs = new EnumWithSlice[subs.length]; for(int i=0;i<subs.length;i++) { this.subs[i] = new EnumWithSlice(); this.subs[i].docsEnum = subs[i].docsEnum; this.subs[i].slice = subs[i].slice; } upto = -1; current = null; return this; } public int getNumSubs() { return numSubs; } public EnumWithSlice[] getSubs() { return subs; } @Override public int freq() { return current.freq(); } @Override public int docID() { return doc; } @Override public int advance(int target) throws IOException { while(true) { if (current != null) { final int doc = current.advance(target-currentBase); if (doc == NO_MORE_DOCS) { current = null; } else { return this.doc = doc + currentBase; } } else if (upto == numSubs-1) { return this.doc = NO_MORE_DOCS; } else { upto++; current = subs[upto].docsEnum; currentBase = subs[upto].slice.start; } } } @Override public int nextDoc() throws IOException { while(true) { if (current == null) { if (upto == numSubs-1) { return this.doc = NO_MORE_DOCS; } else { upto++; current = subs[upto].docsEnum; currentBase = subs[upto].slice.start; } } final int doc = current.nextDoc(); if (doc != NO_MORE_DOCS) { return this.doc = currentBase + doc; } else { current = null; } } } // TODO: implement bulk read more efficiently than super public final static class EnumWithSlice { public DocsEnum docsEnum; public ReaderUtil.Slice slice; } }