org.elasticsearch.common.lucene.search.RegexpFilter Maven / Gradle / Ivy
/*
* 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.search;
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.MultiTermQueryWrapperFilter;
import org.apache.lucene.search.RegexpQuery;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.automaton.RegExp;
import java.io.IOException;
/**
* A lazy regexp filter which only builds the automaton on the first call to {@link #getDocIdSet(AtomicReaderContext, Bits)}.
* It is not thread safe (so can't be applied on multiple segments concurrently)
*/
public class RegexpFilter extends Filter {
private final Term term;
private final int flags;
// use delegation here to support efficient implementation of equals & hashcode for this
// filter (as it will be used as the filter cache key)
private final InternalFilter filter;
public RegexpFilter(Term term) {
this(term, RegExp.ALL);
}
public RegexpFilter(Term term, int flags) {
filter = new InternalFilter(term, flags);
this.term = term;
this.flags = flags;
}
public String field() {
return term.field();
}
public String regexp() {
return term.text();
}
public int flags() {
return flags;
}
@Override
public DocIdSet getDocIdSet(AtomicReaderContext context, Bits acceptDocs) throws IOException {
return filter.getDocIdSet(context, acceptDocs);
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
org.elasticsearch.common.lucene.search.RegexpFilter that = (org.elasticsearch.common.lucene.search.RegexpFilter) o;
if (flags != that.flags) return false;
if (term != null ? !term.equals(that.term) : that.term != null) return false;
return true;
}
@Override
public int hashCode() {
int result = term != null ? term.hashCode() : 0;
result = 31 * result + flags;
return result;
}
@Override
public String toString() {
// todo should we also show the flags?
return term.field() + ":" + term.text();
}
static class InternalFilter extends MultiTermQueryWrapperFilter {
public InternalFilter(Term term) {
super(new RegexpQuery(term));
}
public InternalFilter(Term term, int flags) {
super(new RegexpQuery(term, flags));
}
}
}