org.wltea.analyzer.lucene.IKTokenizer Maven / Gradle / Ivy
/*
* IK 中文分词 版本 7.7.1
* IK Analyzer release 7.7.1
*
* 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.
*
* 源代码由林良益([email protected])提供
* 版权声明 2012，乌龙茶工作室
* provided by Linliangyi and copyright 2012 by Oolong studio
*
* 7.7.1版本 由 Magese ([email protected]) 更新
* release 7.7.1 update by Magese([email protected])
*
*/
package org.wltea.analyzer.lucene;
import org.apache.lucene.analysis.Tokenizer;
import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
import org.apache.lucene.analysis.tokenattributes.OffsetAttribute;
import org.apache.lucene.analysis.tokenattributes.TypeAttribute;
import org.apache.lucene.util.AttributeFactory;
import org.wltea.analyzer.core.IKSegmenter;
import org.wltea.analyzer.core.Lexeme;
import java.io.IOException;
/**
* IK分词器 Lucene Tokenizer适配器类
* 兼容Lucene 4.0版本
*/
@SuppressWarnings("unused")
public final class IKTokenizer extends Tokenizer {
//IK分词器实现
private IKSegmenter _IKImplement;
//词元文本属性
private CharTermAttribute termAtt;
//词元位移属性
private OffsetAttribute offsetAtt;
//词元分类属性（该属性分类参考org.wltea.analyzer.core.Lexeme中的分类常量）
private TypeAttribute typeAtt;
//记录最后一个词元的结束位置
private int endPosition;
/**
* Lucene 7.6 Tokenizer适配器类构造函数
*/
public IKTokenizer() {
this(false);
}
IKTokenizer(boolean useSmart) {
super();
init(useSmart);
}
public IKTokenizer(AttributeFactory factory) {
this(factory, false);
}
IKTokenizer(AttributeFactory factory, boolean useSmart) {
super(factory);
init(useSmart);
}
private void init(boolean useSmart) {
offsetAtt = addAttribute(OffsetAttribute.class);
termAtt = addAttribute(CharTermAttribute.class);
typeAtt = addAttribute(TypeAttribute.class);
_IKImplement = new IKSegmenter(input , useSmart);
}
/* (non-Javadoc)
* @see org.apache.lucene.analysis.TokenStream#incrementToken()
*/
@Override
public boolean incrementToken() throws IOException {
//清除所有的词元属性
clearAttributes();
Lexeme nextLexeme = _IKImplement.next();
if(nextLexeme != null){
//将Lexeme转成Attributes
//设置词元文本
termAtt.append(nextLexeme.getLexemeText());
//设置词元长度
termAtt.setLength(nextLexeme.getLength());
//设置词元位移
offsetAtt.setOffset(nextLexeme.getBeginPosition(), nextLexeme.getEndPosition());
//记录分词的最后位置
endPosition = nextLexeme.getEndPosition();
//记录词元分类
typeAtt.setType(nextLexeme.getLexemeTypeString());
//返会true告知还有下个词元
return true;
}
//返会false告知词元输出完毕
return false;
}
/*
* (non-Javadoc)
* @see org.apache.lucene.analysis.Tokenizer#reset(java.io.Reader)
*/
@Override
public void reset() throws IOException {
super.reset();
_IKImplement.reset(input);
}
@Override
public final void end() {
// set final offset
int finalOffset = correctOffset(this.endPosition);
offsetAtt.setOffset(finalOffset, finalOffset);
}
}