http://lucene.apache.org/lucene-parent/lucene-analyzers-common: Additional Analyzers (The Apache Software Foundation) 
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Analyzer for Chinese, Japanese, and Korean, which indexes bigrams. 
This analyzer generates bigram terms, which are overlapping groups of two adjacent Han, Hiragana, Katakana, or Hangul characters.


Three analyzers are provided for Chinese, each of which treats Chinese text in a different way.

    
 
  • ChineseAnalyzer (in the analyzers/cn package): Index unigrams (individual Chinese characters) as a token.
 
  • CJKAnalyzer (in this package): Index bigrams (overlapping groups of two adjacent Chinese characters) as tokens.
 
  • SmartChineseAnalyzer (in the analyzers/smartcn package): Index words (attempt to segment Chinese text into words) as tokens.


Example phrase： "我是中国人"

    
 
  1. ChineseAnalyzer: 我－是－中－国－人
    2. 
 
  2. CJKAnalyzer: 我是－是中－中国－国人
    3. 
 
  3. SmartChineseAnalyzer: 我－是－中国－人
    4. 



/**
 * Analyzer for Chinese, Japanese, and Korean, which indexes bigrams. 
 * This analyzer generates bigram terms, which are overlapping groups of two adjacent Han, Hiragana, Katakana, or Hangul characters.
 * <p>
 * Three analyzers are provided for Chinese, each of which treats Chinese text in a different way.
 * <ul>
 *  <li>ChineseAnalyzer (in the analyzers/cn package): Index unigrams (individual Chinese characters) as a token.
 *  <li>CJKAnalyzer (in this package): Index bigrams (overlapping groups of two adjacent Chinese characters) as tokens.
 *  <li>SmartChineseAnalyzer (in the analyzers/smartcn package): Index words (attempt to segment Chinese text into words) as tokens.
 * </ul>
 * 
 * Example phrase： "我是中国人"
 * <ol>
 *  <li>ChineseAnalyzer: 我－是－中－国－人</li>
 *  <li>CJKAnalyzer: 我是－是中－中国－国人</li>
 *  <li>SmartChineseAnalyzer: 我－是－中国－人</li>
 * </ol>
 */
package org.apache.lucene.analysis.cjk;