【Lucene3.6.2入门系列】第09节_高级搜索之自定义QueryParser

package com.jadyer.lucene;

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.NumericField;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
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.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;

import com.jadyer.custom.MyQueryParser;

/**
 * 【Lucene3.6.2入门系列】第09节_高级搜索之自定义QueryParser
 * @create Aug 19, 2013 2:07:32 PM
 * @author 玄玉<http://blog.csdn.net/jadyer>
 */
public class AdvancedSearch {
	private Directory directory;
	private IndexReader reader;
	
	public AdvancedSearch(){
		/**文件大小*/
		int[] sizes = {90, 10, 20, 10, 60, 50};
		/**文件名*/
		String[] names = {"Michael.java", "Scofield.ini", "Tbag.txt", "Jack", "Jade", "Jadyer"};
		/**文件内容*/
		String[] contents = {"my java blog is http://blog.csdn.net/jadyer",
							 "my Java Website is http://www.jadyer.cn",
							 "my name is jadyer",
							 "I am a Java Developer",
							 "I am from Haerbin",
							 "I like java of Lucene"};
		/**文件日期*/
		Date[] dates = new Date[sizes.length];
		SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd HH:mm:ss");
		IndexWriter writer = null;
		Document doc = null;
		try {
			dates[0] = sdf.parse("20130407 15:25:30");
			dates[1] = sdf.parse("20130407 16:30:45");
			dates[2] = sdf.parse("20130213 11:15:25");
			dates[3] = sdf.parse("20130808 09:30:55");
			dates[4] = sdf.parse("20130526 13:54:22");
			dates[5] = sdf.parse("20130701 17:35:34");
			directory = FSDirectory.open(new File("myExample/01_index/"));
			writer = new IndexWriter(directory, new IndexWriterConfig(Version.LUCENE_36, new StandardAnalyzer(Version.LUCENE_36)));
			writer.deleteAll();
			for(int i=0; i<sizes.length; i++){
				doc = new Document();
				doc.add(new NumericField("size",Field.Store.YES, true).setIntValue(sizes[i]));
				doc.add(new Field("name", names[i], Field.Store.YES, Field.Index.ANALYZED_NO_NORMS));
				doc.add(new Field("content", contents[i], Field.Store.NO, Field.Index.ANALYZED));
				doc.add(new NumericField("date", Field.Store.YES, true).setLongValue(dates[i].getTime()));
				writer.addDocument(doc);
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			if(null != writer){
				try {
					writer.close();
				} catch (IOException ce) {
					ce.printStackTrace();
				}
			}
		}
	}
	
	
	/**
	 * 获取IndexReader实例
	 */
	private IndexReader getIndexReader(){
		try {
			if(reader == null){
				reader = IndexReader.open(directory);
			}else{
				//if the index was changed since the provided reader was opened, open and return a new reader; else,return null
				//如果当前reader在打开期间index发生改变,则打开并返回一个新的IndexReader,否则返回null
				IndexReader ir = IndexReader.openIfChanged(reader);
				if(ir != null){
					reader.close(); //关闭原reader
					reader = ir;    //赋予新reader
				}
			}
			return reader;
		}catch(Exception e) {
			e.printStackTrace();
		}
		return null; //发生异常则返回null
	}

	
	/**
	 * 自定义QueryParser的搜索
	 * @param expr 搜索的表达式
	 */
	public void searchByCustomQueryParser(String expr){
		IndexSearcher searcher = new IndexSearcher(this.getIndexReader());
		QueryParser parser = new MyQueryParser(Version.LUCENE_36, "content", new StandardAnalyzer(Version.LUCENE_36));
		try {
			Query query = parser.parse(expr);
			TopDocs tds = searcher.search(query, 10);
			for(ScoreDoc sd : tds.scoreDocs){
				Document doc = searcher.doc(sd.doc);
				System.out.print("文档编号=" + sd.doc + "  文档权值=" + doc.getBoost() + "  文档评分=" + sd.score + "    ");
				System.out.println("size=" + doc.get("size") + "  date=" + new SimpleDateFormat("yyyyMMdd HH:mm:ss").format(new Date(Long.parseLong(doc.get("date")))) + "  name=" + doc.get("name"));
			}
		} catch (ParseException e) {
			System.err.println(e.getMessage());
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			if(null != searcher){
				try {
					searcher.close(); //记得关闭IndexSearcher
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}
	
	
	/**
	 * 测试一下搜索效果
	 */
	public static void main(String[] args) {
		AdvancedSearch advancedSearch = new AdvancedSearch();
		advancedSearch.searchByCustomQueryParser("name:Jadk~");
		advancedSearch.searchByCustomQueryParser("name:Ja??er");
		System.out.println("------------------------------------------------------------------------");
		advancedSearch.searchByCustomQueryParser("name:Jade");
		System.out.println("------------------------------------------------------------------------");
		advancedSearch.searchByCustomQueryParser("name:[h TO n]");
		System.out.println("------------------------------------------------------------------------");
		advancedSearch.searchByCustomQueryParser("size:[20 TO 80]");
		System.out.println("------------------------------------------------------------------------");
		advancedSearch.searchByCustomQueryParser("date:[20130407 TO 20130701]");
	}
}

下面是自定义的MyQueryParser.java（这里主要实现了以下两个功能）

1)禁用模糊搜索和通配符搜索，以提高搜索性能

2)扩展基于数字和日期的搜索，使之支持数字和日期的搜索

package com.jadyer.custom;

import java.text.SimpleDateFormat;
import java.util.regex.Pattern;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.queryParser.ParseException;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.NumericRangeQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.util.Version;

/**
 * 自定义QueryParser
 * @see --------------------------------------------------------------------------------------------------
 * @see 实际使用QueryParser的过程中,通常会考虑两个问题
 * @see 1)限制性能低的QueryParser--对于某些QueryParser在搜索时会使得性能降低,故考虑禁用这些搜索以提升性能
 * @see 2)扩展基于数字和日期的搜索---有时需要进行一个数字的范围搜索,故需扩展原有的QueryParser才能实现此搜索
 * @see --------------------------------------------------------------------------------------------------
 * @see 限制性能低的QueryParser
 * @see 继承QueryParser类并重载相应方法,比如getFuzzyQuery和getWildcardQuery
 * @see 这样造成的结果就是,当输入普通的搜索表达式时,如'I AND Haerbin'可以正常搜索
 * @see 但输入'name:Jadk~'或者'name:Ja??er'时,就会执行到重载方法中,这时就可以自行处理了,比如本例中禁止该功能
 * @see --------------------------------------------------------------------------------------------------
 * @see 扩展基于数字和日期的查询
 * @see 思路就是继承QueryParser类后重载getRangeQuery()方法
 * @see 再针对数字和日期的'域',做特殊处理(使用NumericRangeQuery.newIntRange()方法来搜索)
 * @see --------------------------------------------------------------------------------------------------
 * @create Aug 6, 2013 4:13:42 PM
 * @author 玄玉<http://blog.csdn.net/jadyer>
 */
public class MyQueryParser extends QueryParser {
	public MyQueryParser(Version matchVersion, String f, Analyzer a) {
		super(matchVersion, f, a);
	}
	
	@Override
	protected Query getWildcardQuery(String field, String termStr) throws ParseException {
		throw new ParseException("由于性能原因，已禁用通配符搜索，请输入更精确的信息进行搜索 ^_^ ^_^");
	}
	
	@Override
	protected Query getFuzzyQuery(String field, String termStr, float minSimilarity) throws ParseException {
		throw new ParseException("由于性能原因，已禁用模糊搜索，请输入更精确的信息进行搜索 ^_^ ^_^");
	}
	
	@Override
	protected Query getRangeQuery(String field, String part1, String part2, boolean inclusive) throws ParseException {
		if(field.equals("size")){
			//默认的QueryParser.parse(String query)表达式中并不支持'size:[20 TO 80]'数字的域值
			//这样一来,针对数字的域值进行特殊处理,那么QueryParser表达式就支持数字了
			return NumericRangeQuery.newIntRange(field, Integer.parseInt(part1), Integer.parseInt(part2), inclusive, inclusive);
		}else if(field.equals("date")){
			String regex = "\\d{8}";
			String dateType = "yyyyMMdd";
			if(Pattern.matches(regex, part1) && Pattern.matches(regex, part2)){
				SimpleDateFormat sdf = new SimpleDateFormat(dateType);
				try {
					long min = sdf.parse(part1).getTime();
					long max = sdf.parse(part2).getTime();
					//使之支持日期的检索,应用时直接QueryParser.parse("date:[20130407 TO 20130701]")
					return NumericRangeQuery.newLongRange(field, min, max, inclusive, inclusive);
				} catch (java.text.ParseException e) {
					e.printStackTrace();
				}
			}else{
				throw new ParseException("Unknown date format, please use '" + dateType + "'");
			}
		}
		//如没找到匹配的Field域,那么返回默认的TermRangeQuery
		return super.getRangeQuery(field, part1, part2, inclusive);
	}
}