package org.apache.lucene.search; /** * 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 org.apache.lucene.index.IndexReader; import org.apache.lucene.index.Term; import org.apache.lucene.util.BytesRef; /** * Subclass of FilteredTermsEnum for enumerating a single term. * <p> * This can be used by {@link MultiTermQuery}s that need only visit one term, * but want to preserve MultiTermQuery semantics such as * {@link MultiTermQuery#rewriteMethod}. */ public final class SingleTermsEnum extends FilteredTermsEnum { private final BytesRef singleRef; /** * Creates a new <code>SingleTermsEnum</code>. * <p> * After calling the constructor the enumeration is already pointing to the term, * if it exists. */ public SingleTermsEnum(IndexReader reader, Term singleTerm) throws IOException { super(reader, singleTerm.field()); singleRef = singleTerm.bytes(); setInitialSeekTerm(singleRef); } @Override protected AcceptStatus accept(BytesRef term) { return term.equals(singleRef) ? AcceptStatus.YES : AcceptStatus.END; } }