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IK 分词器项目maven版.发布到maven中央仓库
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/**
*
* IK 中文分词 版本 5.0
* IK Analyzer release 5.0
*
* 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
*
*/
package org.wltea.analyzer.dic;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
/**
* 词典树分段，表示词典树的一个分枝
*/
class DictSegment implements Comparable{
//公用字典表，存储汉字
private static final Map charMap = new HashMap(16 , 0.95f);
//数组大小上限
private static final int ARRAY_LENGTH_LIMIT = 3;
//Map存储结构
private Map childrenMap;
//数组方式存储结构
private DictSegment[] childrenArray;
//当前节点上存储的字符
private Character nodeChar;
//当前节点存储的Segment数目
//storeSize <=ARRAY_LENGTH_LIMIT ，使用数组存储， storeSize >ARRAY_LENGTH_LIMIT ,则使用Map存储
private int storeSize = 0;
//当前DictSegment状态 ,默认 0 , 1表示从根节点到当前节点的路径表示一个词
private int nodeState = 0;
DictSegment(Character nodeChar){
if(nodeChar == null){
throw new IllegalArgumentException("参数为空异常，字符不能为空");
}
this.nodeChar = nodeChar;
}
Character getNodeChar() {
return nodeChar;
}
/*
* 判断是否有下一个节点
*/
boolean hasNextNode(){
return this.storeSize > 0;
}
/**
* 匹配词段
* @param charArray
* @return Hit
*/
Hit match(char[] charArray){
return this.match(charArray , 0 , charArray.length , null);
}
/**
* 匹配词段
* @param charArray
* @param begin
* @param length
* @return Hit
*/
Hit match(char[] charArray , int begin , int length){
return this.match(charArray , begin , length , null);
}
/**
* 匹配词段
* @param charArray
* @param begin
* @param length
* @param searchHit
* @return Hit
*/
Hit match(char[] charArray , int begin , int length , Hit searchHit){
if(searchHit == null){
//如果hit为空，新建
searchHit= new Hit();
//设置hit的其实文本位置
searchHit.setBegin(begin);
}else{
//否则要将HIT状态重置
searchHit.setUnmatch();
}
//设置hit的当前处理位置
searchHit.setEnd(begin);
Character keyChar = new Character(charArray[begin]);
DictSegment ds = null;
//引用实例变量为本地变量，避免查询时遇到更新的同步问题
DictSegment[] segmentArray = this.childrenArray;
Map segmentMap = this.childrenMap;
//STEP1 在节点中查找keyChar对应的DictSegment
if(segmentArray != null){
//在数组中查找
DictSegment keySegment = new DictSegment(keyChar);
int position = Arrays.binarySearch(segmentArray, 0 , this.storeSize , keySegment);
if(position >= 0){
ds = segmentArray[position];
}
}else if(segmentMap != null){
//在map中查找
ds = (DictSegment)segmentMap.get(keyChar);
}
//STEP2 找到DictSegment，判断词的匹配状态，是否继续递归，还是返回结果
if(ds != null){
if(length > 1){
//词未匹配完，继续往下搜索
return ds.match(charArray, begin + 1 , length - 1 , searchHit);
}else if (length == 1){
//搜索最后一个char
if(ds.nodeState == 1){
//添加HIT状态为完全匹配
searchHit.setMatch();
}
if(ds.hasNextNode()){
//添加HIT状态为前缀匹配
searchHit.setPrefix();
//记录当前位置的DictSegment
searchHit.setMatchedDictSegment(ds);
}
return searchHit;
}
}
//STEP3 没有找到DictSegment， 将HIT设置为不匹配
return searchHit;
}
/**
* 加载填充词典片段
* @param charArray
*/
void fillSegment(char[] charArray){
this.fillSegment(charArray, 0 , charArray.length , 1);
}
/**
* 屏蔽词典中的一个词
* @param charArray
*/
void disableSegment(char[] charArray){
this.fillSegment(charArray, 0 , charArray.length , 0);
}
/**
* 加载填充词典片段
* @param charArray
* @param begin
* @param length
* @param enabled
*/
private synchronized void fillSegment(char[] charArray , int begin , int length , int enabled){
//获取字典表中的汉字对象
Character beginChar = new Character(charArray[begin]);
Character keyChar = charMap.get(beginChar);
//字典中没有该字，则将其添加入字典
if(keyChar == null){
charMap.put(beginChar, beginChar);
keyChar = beginChar;
}
//搜索当前节点的存储，查询对应keyChar的keyChar，如果没有则创建
DictSegment ds = lookforSegment(keyChar , enabled);
if(ds != null){
//处理keyChar对应的segment
if(length > 1){
//词元还没有完全加入词典树
ds.fillSegment(charArray, begin + 1, length - 1 , enabled);
}else if (length == 1){
//已经是词元的最后一个char,设置当前节点状态为enabled，
//enabled=1表明一个完整的词，enabled=0表示从词典中屏蔽当前词
ds.nodeState = enabled;
}
}
}
/**
* 查找本节点下对应的keyChar的segment *
* @param keyChar
* @param create =1如果没有找到，则创建新的segment ; =0如果没有找到，不创建，返回null
* @return
*/
private DictSegment lookforSegment(Character keyChar , int create){
DictSegment ds = null;
if(this.storeSize <= ARRAY_LENGTH_LIMIT){
//获取数组容器，如果数组未创建则创建数组
DictSegment[] segmentArray = getChildrenArray();
//搜寻数组
DictSegment keySegment = new DictSegment(keyChar);
int position = Arrays.binarySearch(segmentArray, 0 , this.storeSize, keySegment);
if(position >= 0){
ds = segmentArray[position];
}
//遍历数组后没有找到对应的segment
if(ds == null && create == 1){
ds = keySegment;
if(this.storeSize < ARRAY_LENGTH_LIMIT){
//数组容量未满，使用数组存储
segmentArray[this.storeSize] = ds;
//segment数目+1
this.storeSize++;
Arrays.sort(segmentArray , 0 , this.storeSize);
}else{
//数组容量已满，切换Map存储
//获取Map容器，如果Map未创建,则创建Map
Map segmentMap = getChildrenMap();
//将数组中的segment迁移到Map中
migrate(segmentArray , segmentMap);
//存储新的segment
segmentMap.put(keyChar, ds);
//segment数目+1 ， 必须在释放数组前执行storeSize++ ， 确保极端情况下，不会取到空的数组
this.storeSize++;
//释放当前的数组引用
this.childrenArray = null;
}
}
}else{
//获取Map容器，如果Map未创建,则创建Map
Map segmentMap = getChildrenMap();
//搜索Map
ds = (DictSegment)segmentMap.get(keyChar);
if(ds == null && create == 1){
//构造新的segment
ds = new DictSegment(keyChar);
segmentMap.put(keyChar , ds);
//当前节点存储segment数目+1
this.storeSize ++;
}
}
return ds;
}
/**
* 获取数组容器
* 线程同步方法
*/
private DictSegment[] getChildrenArray(){
if(this.childrenArray == null){
synchronized(this){
if(this.childrenArray == null){
this.childrenArray = new DictSegment[ARRAY_LENGTH_LIMIT];
}
}
}
return this.childrenArray;
}
/**
* 获取Map容器
* 线程同步方法
*/
private Map getChildrenMap(){
if(this.childrenMap == null){
synchronized(this){
if(this.childrenMap == null){
this.childrenMap = new HashMap(ARRAY_LENGTH_LIMIT * 2,0.8f);
}
}
}
return this.childrenMap;
}
/**
* 将数组中的segment迁移到Map中
* @param segmentArray
*/
private void migrate(DictSegment[] segmentArray , Map segmentMap){
for(DictSegment segment : segmentArray){
if(segment != null){
segmentMap.put(segment.nodeChar, segment);
}
}
}
/**
* 实现Comparable接口
* @param o
* @return int
*/
public int compareTo(DictSegment o) {
//对当前节点存储的char进行比较
return this.nodeChar.compareTo(o.nodeChar);
}
}