/*
* 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.
*/
package org.apache.lucene.analysis.minhash;
import java.util.Map;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.util.TokenFilterFactory;
/**
* {@link TokenFilterFactory} for {@link MinHashFilter}.
*/
public class MinHashFilterFactory extends TokenFilterFactory {
private int hashCount = MinHashFilter.DEFAULT_HASH_COUNT;
private int bucketCount = MinHashFilter.DEFAULT_BUCKET_COUNT;
private int hashSetSize = MinHashFilter.DEFAULT_HASH_SET_SIZE;
private boolean withRotation;
/**
* Create a {@link MinHashFilterFactory}.
*/
public MinHashFilterFactory(Map<String,String> args) {
super(args);
hashCount = getInt(args, "hashCount", MinHashFilter.DEFAULT_HASH_COUNT);
bucketCount = getInt(args, "bucketCount", MinHashFilter.DEFAULT_BUCKET_COUNT);
hashSetSize = getInt(args, "hashSetSize", MinHashFilter.DEFAULT_HASH_SET_SIZE);
withRotation = getBoolean(args, "withRotation", bucketCount > 1);
}
/*
* (non-Javadoc)
*
* @see org.apache.lucene.analysis.util.TokenFilterFactory#create(org.apache.lucene.analysis.TokenStream)
*/
@Override
public TokenStream create(TokenStream input) {
return new MinHashFilter(input, hashCount, bucketCount, hashSetSize, withRotation);
}
}