org.apache.lucene.analysis.ngram.EdgeNGramTokenizer Maven / Gradle / Ivy
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* 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,
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*/
package org.apache.lucene.analysis.ngram;
import org.apache.lucene.analysis.Tokenizer;
import org.apache.lucene.util.AttributeFactory;
/**
* Tokenizes the input from an edge into n-grams of given size(s).
*
* This {@link Tokenizer} create n-grams from the beginning edge of a input token.
*
As of Lucene 4.4, this class supports
* {@link #isTokenChar(int) pre-tokenization} and correctly handles
* supplementary characters.
*/
public class EdgeNGramTokenizer extends NGramTokenizer {
public static final int DEFAULT_MAX_GRAM_SIZE = 1;
public static final int DEFAULT_MIN_GRAM_SIZE = 1;
/**
* Creates EdgeNGramTokenizer that can generate n-grams in the sizes of the given range
*
* @param minGram the smallest n-gram to generate
* @param maxGram the largest n-gram to generate
*/
public EdgeNGramTokenizer(int minGram, int maxGram) {
super(minGram, maxGram, true);
}
/**
* Creates EdgeNGramTokenizer that can generate n-grams in the sizes of the given range
*
* @param factory {@link org.apache.lucene.util.AttributeFactory} to use
* @param minGram the smallest n-gram to generate
* @param maxGram the largest n-gram to generate
*/
public EdgeNGramTokenizer(AttributeFactory factory, int minGram, int maxGram) {
super(factory, minGram, maxGram, true);
}
}