Java tutorial
/* * Licensed to Elasticsearch under one or more contributor * license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright * ownership. Elasticsearch 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.elasticsearch.common.lucene.docset; import org.apache.lucene.search.DocIdSetIterator; import java.io.IOException; /** */ public abstract class MatchDocIdSetIterator extends DocIdSetIterator { private final int maxDoc; private int doc = -1; public MatchDocIdSetIterator(int maxDoc) { this.maxDoc = maxDoc; } protected abstract boolean matchDoc(int doc); @Override public int docID() { return doc; } @Override public int nextDoc() throws IOException { do { doc++; if (doc >= maxDoc) { return doc = NO_MORE_DOCS; } } while (!matchDoc(doc)); return doc; } @Override public int advance(int target) throws IOException { if (target >= maxDoc) { return doc = NO_MORE_DOCS; } doc = target; while (!matchDoc(doc)) { doc++; if (doc >= maxDoc) { return doc = NO_MORE_DOCS; } } return doc; } }