基于Lucene3.5.0如何从TokenStream获得Token

大家好，又见面了，我是你们的朋友全栈君。通过学习Lucene3.5.0的doc文档，对不同release版本 lucene版本的API改动做分析。最后找到了有价值的改动信息。

• LUCENE-2302: Deprecated TermAttribute and replaced by a new CharTermAttribute. The change is backwards compatible, so mixed new/old TokenStreams all work on the same char[] buffer independent of which interface they use. CharTermAttribute has shorter method names and implements CharSequence and Appendable. This allows usage like Java’s StringBuilder in addition to direct char[] access. Also terms can directly be used in places where CharSequence is allowed (e.g. regular expressions). (Uwe Schindler, Robert Muir)
• 以上信息可以知道，原来的通过的方法已经不能够提取响应的Token了
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  1. StringReader reader = new StringReader(s);  
  2. TokenStream ts =analyzer.tokenStream(s, reader);  
  3. TermAttribute ta = ts.getAttribute(TermAttribute.class);  

  StringReader reader = new StringReader(s);<br />TokenStream ts =analyzer.tokenStream(s, reader);<br />TermAttribute ta = ts.getAttribute(TermAttribute.class);

• 通过分析Api文档信息 可知，CharTermAttribute已经成为替换TermAttribute的接口
• 因此我编写了一个例子来更好的从TokenStream中提取Token
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  1. package com.segment;  
  2.   
  3. import java.io.StringReader;  
  4. import org.apache.lucene.analysis.Analyzer;  
  5. import org.apache.lucene.analysis.Token;  
  6. import org.apache.lucene.analysis.TokenStream;  
  7. import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;  
  8. import org.apache.lucene.analysis.tokenattributes.TermAttribute;  
  9. import org.apache.lucene.util.AttributeImpl;  
  10. import org.wltea.analyzer.lucene.IKAnalyzer;  
  11.   
  12.   
  13. public class Segment {  
  14.     public static String show(Analyzer a, String s) throws Exception {  
  15.   
  16.         StringReader reader = new StringReader(s);  
  17.         TokenStream ts = a.tokenStream(s, reader);  
  18.         String s1 = “”, s2 = “”;  
  19.         boolean hasnext= ts.incrementToken();  
  20.         //Token t = ts.next();  
  21.         while (hasnext) {  
  22.             //AttributeImpl ta = new AttributeImpl();  
  23.             CharTermAttribute ta = ts.getAttribute(CharTermAttribute.class);  
  24.             //TermAttribute ta = ts.getAttribute(TermAttribute.class);  
  25.               
  26.             s2 = ta.toString() + ” “;  
  27.             s1 += s2;  
  28.             hasnext = ts.incrementToken();  
  29.         }  
  30.         return s1;  
  31.     }  
  32.   
  33.     public String segment(String s) throws Exception {  
  34.         Analyzer a = new IKAnalyzer();  
  35.         return show(a, s);  
  36.     }  
  37.     public static void main(String args[])  
  38.     {  
  39.         String name = “我是俊杰，我爱编程，我的测试用例”;  
  40.         Segment s = new Segment();  
  41.         String test = “”;  
  42.         try {  
  43.             System.out.println(test+s.segment(name));  
  44.         } catch (Exception e) {  
  45.             // TODO Auto-generated catch block  
  46.             e.printStackTrace();  
  47.         }  
  48.     }  
  49.   
  50. }