lucene3.6.0的高亮显示

需要引入

		<dependency>
			<groupId>org.apache.lucene</groupId>
			<artifactId>lucene-core</artifactId>
			<version>3.6.0</version>
		</dependency>
		<dependency>
			<groupId>org.apache.lucene</groupId>
			<artifactId>lucene-highlighter</artifactId>
			<version>3.6.0</version>
		</dependency>

示例代码：

import java.io.IOException;
import java.io.StringReader;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
import org.apache.lucene.analysis.tokenattributes.OffsetAttribute;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.highlight.Highlighter;
import org.apache.lucene.search.highlight.InvalidTokenOffsetsException;
import org.apache.lucene.search.highlight.QueryScorer;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;

public class DocSearch {

	private static IndexSearcher isearcher = null;
	public static void search(String key) throws IOException, ParseException, InvalidTokenOffsetsException{
		 Directory directory = FSDirectory.open(new File("E:\\output\\lucence\\index"));
		 // Now search the index:
	    IndexReader ireader = IndexReader.open(directory); // read-only=true
	    isearcher  = new IndexSearcher(ireader);
	    // Parse a simple query that searches for "text":
	    Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_CURRENT);
	    
//	    TokenStream tokenStream = analyzer.tokenStream("context", new StringReader("this is a quick gooobuy"));
//	    OffsetAttribute offsetAttribute = tokenStream.addAttribute(OffsetAttribute.class);
//	    CharTermAttribute charTermAttribute = tokenStream.addAttribute(CharTermAttribute.class);
//
//	    while (tokenStream.incrementToken()) {
//	        int startOffset = offsetAttribute.startOffset();
//	        int endOffset = offsetAttribute.endOffset();
//	        String term = charTermAttribute.toString();
//	        System.out.println(offsetAttribute.toString() + "\t" + term);
//	    }
	    
	    QueryParser parser = new QueryParser(Version.LUCENE_CURRENT,"context", analyzer);
	    Query query = parser.parse(key);
	    ScoreDoc[] hits = isearcher.search(query, null, 1000).scoreDocs;
	    
	    Highlighter hl = new Highlighter(new QueryScorer(query));
	    
	    System.out.println(query.toString());
	    // Iterate through the results:
	    for (int i = 0; i < hits.length; i++) {
	      Document hitDoc = isearcher.doc(hits[i].doc);
	      TokenStream ts = analyzer.tokenStream("context", new StringReader(hitDoc.getValues("context")[0]));
	      String frament = hl.getBestFragment(ts, hitDoc.getValues("context")[0]);
	      System.out.println(frament);
//	      System.out.println(hitDoc.getValues("id")[0] + "\t" + hitDoc.getValues("context")[0] + "\t" + hits[i].score);
//	      Explanation explan = isearcher.explain(query, hits[i].doc);
//	      System.out.println(explan);
	    }
	}
	
	public static void main(String[] args) throws IOException, ParseException, InvalidTokenOffsetsException {
		search("旧水泥袋");
		isearcher.close();
	}
	
}

索引建立和数据参考http://zhwj184.iteye.com/admin/blogs/1522709

 

输出结果：

context:旧 context:水 context:泥 context:袋
采购<B>旧</B>编织<B>袋</B>、<B>旧</B><B>水</B><B>泥</B><B>袋</B>
<B>水</B><B>泥</B>
采购<B>水</B><B>泥</B>电阻
求购<B>水</B><B>泥</B>输送链条和提升机
1万5 潜<B>水</B>料啤酒手提包 手提<B>袋</B>
大量采购包装用的编织<B>袋</B>（新的<B>旧</B>的，有无商标皆可）
铁<B>泥</B> 铁灰
废<B>旧</B>砂轮
软陶<B>泥</B>，超轻粘土
<B>水</B>泵
手<B>袋</B>
<B>水</B>锈石 上<B>水</B>石  吸<B>水</B>石
足浴<B>袋</B>  泡脚<B>袋</B> 异形<B>袋</B>
手提<B>袋</B>制<B>袋</B>机
回收库存废<B>旧</B>油墨油漆
回收库存<B>旧</B>油漆13463048572
求购废<B>旧</B>油漆油墨13463048572
求购库存<B>旧</B>化工树脂

highlighter类的分析

/**
 * Class used to markup highlighted terms found in the best sections of a
 * text, using configurable {@link Fragmenter}, {@link Scorer}, {@link Formatter},
 * {@link Encoder} and tokenizers.
 */
public class Highlighter
{
  public static final int DEFAULT_MAX_CHARS_TO_ANALYZE = 50*1024;

  private int maxDocCharsToAnalyze = DEFAULT_MAX_CHARS_TO_ANALYZE;
	private Formatter formatter;
	private Encoder encoder;
	private Fragmenter textFragmenter=new SimpleFragmenter();
	private Scorer fragmentScorer=null;

	public Highlighter(Scorer fragmentScorer)
	{
		this(new SimpleHTMLFormatter(),fragmentScorer);
	}


 	public Highlighter(Formatter formatter, Scorer fragmentScorer)
 	{
		this(formatter,new DefaultEncoder(),fragmentScorer);
	}


	public Highlighter(Formatter formatter, Encoder encoder, Scorer fragmentScorer)
	{
 		this.formatter = formatter;
		this.encoder = encoder;
 		this.fragmentScorer = fragmentScorer;
 	}

这里有两个扩展，formatter和encoder，formatter其实就是堆高亮部分的显示逻辑，比如默认是直接加<B></B>,encoder编码这里默认是不错任何处理，这里可以对输入的文本进行编码处理，

 

可以查看highlighter的encoder的一个默认实现

package org.apache.lucene.search.highlight;
/**
 * Copyright 2005 The Apache Software Foundation
 *
 * Licensed 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.
 */

/**
 * Simple {@link Encoder} implementation to escape text for HTML output
 *
 */
public class SimpleHTMLEncoder implements Encoder
{
	public SimpleHTMLEncoder()
	{
	}

	public String encodeText(String originalText)
	{
		return htmlEncode(originalText);
	}
	
	/**
	 * Encode string into HTML
	 */
	public final static String htmlEncode(String plainText) 
	{
		if (plainText == null || plainText.length() == 0)
		{
			return "";
		}

		StringBuilder result = new StringBuilder(plainText.length());

		for (int index=0; index<plainText.length(); index++) 
		{
			char ch = plainText.charAt(index);

			switch (ch) 
			{
			case '"':
				result.append(""");
				break;

			case '&':
				result.append("&");
				break;

			case '<':
				result.append("<");
				break;

			case '>':
				result.append(">");
				break;

			default:
				   if (ch < 128) 
				   {
			           result.append(ch);
			       } 
				   else 
			       {
			           result.append("&#").append((int)ch).append(";");
			       }
			}
		}

		return result.toString();
	}
}

formatter的默认实现

package org.apache.lucene.search.highlight;

/**
 * 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.
 */

/**
 * Simple {@link Formatter} implementation to highlight terms with a pre and
 * post tag.
 */
public class SimpleHTMLFormatter implements Formatter {
  
  private static final String DEFAULT_PRE_TAG = "<B>";
  private static final String DEFAULT_POST_TAG = "</B>";
  
	private String preTag;
	private String postTag;
	
	public SimpleHTMLFormatter(String preTag, String postTag) {
		this.preTag = preTag;
		this.postTag = postTag;
	}

	/** Default constructor uses HTML: <B> tags to markup terms. */
	public SimpleHTMLFormatter() {
	  this(DEFAULT_PRE_TAG, DEFAULT_POST_TAG);
	}

	/* (non-Javadoc)
	 * @see org.apache.lucene.search.highlight.Formatter#highlightTerm(java.lang.String, org.apache.lucene.search.highlight.TokenGroup)
	 */
	public String highlightTerm(String originalText, TokenGroup tokenGroup) {
	  if (tokenGroup.getTotalScore() <= 0) {
	    return originalText;
	  }
	  
	  // Allocate StringBuilder with the right number of characters from the
    // beginning, to avoid char[] allocations in the middle of appends.
	  StringBuilder returnBuffer = new StringBuilder(preTag.length() + originalText.length() + postTag.length());
	  returnBuffer.append(preTag);
	  returnBuffer.append(originalText);
	  returnBuffer.append(postTag);
	  return returnBuffer.toString();
	}
	
}