package org.apache.lucene.search.regex;
/**
* 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.search.FilteredTermsEnum;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.util.BytesRef;
import java.io.IOException;
/**
* Subclass of FilteredTermEnum for enumerating all terms that match the
* specified regular expression term using the specified regular expression
* implementation.
* <p>
* Term enumerations are always ordered by Term.compareTo(). Each term in
* the enumeration is greater than all that precede it.
*/
public class RegexTermsEnum extends FilteredTermsEnum {
private RegexCapabilities.RegexMatcher regexImpl;
private final BytesRef prefixRef;
public RegexTermsEnum(IndexReader reader, Term term, RegexCapabilities regexCap) throws IOException {
super(reader, term.field());
String text = term.text();
this.regexImpl = regexCap.compile(text);
String pre = regexImpl.prefix();
if (pre == null) pre = "";
setInitialSeekTerm(prefixRef = new BytesRef(pre));
}
@Override
protected AcceptStatus accept(BytesRef term) {
if (term.startsWith(prefixRef)) {
// TODO: set BoostAttr based on distance of
// searchTerm.text() and term().text()
return regexImpl.match(term) ? AcceptStatus.YES : AcceptStatus.NO;
} else {
return AcceptStatus.NO;
}
}
}