1 package org.apache.lucene.search;
4 * Licensed to the Apache Software Foundation (ASF) under one or more
5 * contributor license agreements. See the NOTICE file distributed with
6 * this work for additional information regarding copyright ownership.
7 * The ASF licenses this file to You under the Apache License, Version 2.0
8 * (the "License"); you may not use this file except in compliance with
9 * the License. You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
20 import java.io.IOException;
22 import org.apache.lucene.index.IndexReader;
23 import org.apache.lucene.index.Term;
26 * Subclass of FilteredTermEnum for enumerating all terms that match the
27 * specified prefix filter term.
29 * Term enumerations are always ordered by Term.compareTo(). Each term in
30 * the enumeration is greater than all that precede it.
33 public class PrefixTermEnum extends FilteredTermEnum {
35 private final Term prefix;
36 private boolean endEnum = false;
38 public PrefixTermEnum(IndexReader reader, Term prefix) throws IOException {
41 setEnum(reader.terms(new Term(prefix.field(), prefix.text())));
45 public float difference() {
50 protected boolean endEnum() {
54 protected Term getPrefixTerm() {
59 protected boolean termCompare(Term term) {
60 if (term.field() == prefix.field() && term.text().startsWith(prefix.text())) {