lucene实现自定义的评分

朴灿烈づ我的快乐病毒、 2022-03-01 07:50 208阅读 0赞

1、工程目录

![20130501213737502][]

2、自定义评分一、根据文件大小来评分，文件越大，权重越低

package util;
    
    import java.io.IOException;
    import org.apache.lucene.index.IndexReader;
    import org.apache.lucene.index.Term;
    import org.apache.lucene.search.IndexSearcher;
    import org.apache.lucene.search.Query;
    import org.apache.lucene.search.TermQuery;
    import org.apache.lucene.search.TopDocs;
    import org.apache.lucene.search.function.CustomScoreProvider;
    import org.apache.lucene.search.function.CustomScoreQuery;
    import org.apache.lucene.search.function.FieldScoreQuery;
    import org.apache.lucene.search.function.ValueSourceQuery;
    import org.apache.lucene.search.function.FieldScoreQuery.Type;
    
    public class MyScoreQuery1{
    	
    	public void searchByScoreQuery() throws Exception{
    		IndexSearcher searcher = DocUtil.getSearcher();
    		Query query = new TermQuery(new Term("content","java"));
    		
    		//1、创建评分域，如果Type是String类型，那么是Type.BYTE
    		//该域必须是数值型的，并且不能使用norms索引，以及每个文档中该域只能由一个语汇
    		//单元，通常可用Field.Index.not_analyzer_no_norms来进行创建索引
    		FieldScoreQuery fieldScoreQuery = new FieldScoreQuery("size",Type.INT);
    		//2、根据评分域和原有的Query创建自定义的Query对象
    		//query是原有的query，fieldScoreQuery是专门做评分的query
    		MyCustomScoreQuery customQuery = new MyCustomScoreQuery(query, fieldScoreQuery);
    		
    		TopDocs topdoc = searcher.search(customQuery, 100);
    		DocUtil.printDocument(topdoc, searcher);
    		searcher.close();
    		
    	}
    	
    	@SuppressWarnings("serial")
    	private class MyCustomScoreQuery extends CustomScoreQuery{
    
    		public MyCustomScoreQuery(Query subQuery, ValueSourceQuery valSrcQuery) {
    			super(subQuery, valSrcQuery);
    		}
    		
    		/**
    		 * 这里的reader是针对段的，意思是如果索引包含的段不止一个，那么搜索期间会多次调用
    		 * 这个方法，强调这点是重要的，因为它使你的评分逻辑能够有效使用段reader来对域缓存
    		 * 中的值进行检索
    		 */
    		@Override
    		protected CustomScoreProvider getCustomScoreProvider(IndexReader reader)
    				throws IOException {
    			//默认情况实现的评分是通过原有的评分*传入进来的评分域所获取的评分来确定最终打分的
    			//为了根据不同的需求进行评分，需要自己进行评分的设定
    			/**
    			 * 自定评分的步骤
    			 * 创建一个类继承于CustomScoreProvider
    			 * 覆盖customScore方法
    			 */
    //			return super.getCustomScoreProvider(reader);
    			return new MyCustomScoreProvider(reader);
    		}
    		
    		
    	}
    	
    	private class MyCustomScoreProvider extends CustomScoreProvider{
    
    		public MyCustomScoreProvider(IndexReader reader) {
    			super(reader);
    		}
    		
    		/**
    		 * subQueryScore表示默认文档的打分
    		 * valSrcScore表示的评分域的打分
    		 * 默认是subQueryScore*valSrcScore返回的
    		 */
    		@Override
    		public float customScore(int doc, float subQueryScore, float valSrcScore)throws IOException {
    			System.out.println("Doc:"+doc);
    			System.out.println("subQueryScore:"+subQueryScore);
    			System.out.println("valSrcScore:"+valSrcScore);
    //			return super.customScore(doc, subQueryScore, valSrcScore);
    			return subQueryScore / valSrcScore;
    		}
    		
    	}
    }

3、根据特定的几个文件名来评分，选中的文件名权重变大

package util;
    
    import java.io.IOException;
    import org.apache.lucene.index.IndexReader;
    import org.apache.lucene.index.Term;
    import org.apache.lucene.search.FieldCache;
    import org.apache.lucene.search.IndexSearcher;
    import org.apache.lucene.search.Query;
    import org.apache.lucene.search.TermQuery;
    import org.apache.lucene.search.TopDocs;
    import org.apache.lucene.search.function.CustomScoreProvider;
    import org.apache.lucene.search.function.CustomScoreQuery;
    /**
     * 此类的功能是给特定的文件名加权，也就是加评分
     * 也可以实现搜索书籍的时候把近一两年的出版的图书给增加权重
     * @author user
     */
    public class MyScoreQuery2 {
    	public void searchByFileScoreQuery() throws Exception{
    		IndexSearcher searcher = DocUtil.getSearcher();
    		Query query = new TermQuery(new Term("content","java"));
    		
    		FilenameScoreQuery fieldScoreQuery = new FilenameScoreQuery(query);
    		
    		TopDocs topdoc = searcher.search(fieldScoreQuery, 100);
    		DocUtil.printDocument(topdoc, searcher);
    		searcher.close();
    		
    	}
    	
    	@SuppressWarnings("serial")
    	private class FilenameScoreQuery extends CustomScoreQuery{
    
    		public FilenameScoreQuery(Query subQuery) {
    			super(subQuery);
    		}
    
    		@Override
    		protected CustomScoreProvider getCustomScoreProvider(IndexReader reader)
    				throws IOException {
    //			return super.getCustomScoreProvider(reader);
    			return new FilenameScoreProvider(reader);
    		}
    	}
    	
    	private class FilenameScoreProvider extends CustomScoreProvider{
    		String[] filenames = null;
    		public FilenameScoreProvider(IndexReader reader) {
    			super(reader);
    			try {
    				filenames = FieldCache.DEFAULT.getStrings(reader, "filename");
    			} catch (IOException e) {e.printStackTrace();}
    		}
    
    		//如何根据doc获取相应的field的值
    		/*
    		 * 在reader没有关闭之前，所有的数据会存储要一个域缓存中，可以通过域缓存获取很多有用
    		 * 的信息filenames = FieldCache.DEFAULT.getStrings(reader, "filename");可以获取
    		 * 所有的filename域的信息
    		 */
    		@Override
    		public float customScore(int doc, float subQueryScore, float valSrcScore)
    				throws IOException {
    			String fileName = filenames[doc];
    			System.out.println(doc+":"+fileName);
    //			return super.customScore(doc, subQueryScore, valSrcScore);
    			if("9.txt".equals(fileName) || "4.txt".equals(fileName)) {
    				return subQueryScore*1.5f;
    			}
    			return subQueryScore/1.5f;
    		}
    		
    	}
    }

4、测试junit

package test;
    import org.junit.Test;
    import util.MyScoreQuery1;
    import util.MyScoreQuery2;
    
    public class TestCustomScore {
    
    	@Test
    	public void test01() throws Exception {
    		MyScoreQuery1 msq = new MyScoreQuery1();
    		msq.searchByScoreQuery();
    	}
    	
    	@Test
    	public void test02() throws Exception {
    		MyScoreQuery2 msq = new MyScoreQuery2();
    		msq.searchByFileScoreQuery();
    	}
    }

5、文档操作的工具类

package util;
    
    import java.io.File;
    import java.io.IOException;
    import java.text.SimpleDateFormat;
    import java.util.Date;
    import org.apache.lucene.document.Document;
    import org.apache.lucene.index.CorruptIndexException;
    import org.apache.lucene.index.IndexReader;
    import org.apache.lucene.search.IndexSearcher;
    import org.apache.lucene.search.ScoreDoc;
    import org.apache.lucene.search.TopDocs;
    import org.apache.lucene.store.Directory;
    import org.apache.lucene.store.FSDirectory;
    
    public class DocUtil {
    	private static IndexReader reader;
    	//得到indexSearch对象
    	public static IndexSearcher getSearcher(){
    		try {
    			Directory directory = FSDirectory.open(new File("D:\\Workspaces\\customscore\\index"));
    			reader = IndexReader.open(directory);
    		} catch (CorruptIndexException e) {
    			e.printStackTrace();
    		} catch (IOException e) {
    			e.printStackTrace();
    		}
    		IndexSearcher searcher = new IndexSearcher(reader);
    		return searcher;
    	}
    	
    	/**
    	 * 打印文档信息
    	 * @param topdoc
    	 */
    	public static void printDocument(TopDocs topdoc,IndexSearcher searcher){
    		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
    		for(ScoreDoc scoredoc : topdoc.scoreDocs){
    			try {
    				Document doc = searcher.doc(scoredoc.doc);
    				System.out.println(scoredoc.doc+":("+scoredoc.score+")" +
    						"["+doc.get("filename")+"【"+doc.get("path")+"】--->"+
    						doc.get("size")+"-----"+sdf.format(new Date(Long.valueOf(doc.get("date"))))+"]");
    			} catch (CorruptIndexException e) {
    				e.printStackTrace();
    			} catch (IOException e) {
    				e.printStackTrace();
    			}
    		}
    	}
    }

6、创建索引

package index;
    import java.io.File;
    import java.io.IOException;
    import org.apache.commons.io.FileUtils;
    import org.apache.lucene.analysis.Analyzer;
    import org.apache.lucene.document.Document;
    import org.apache.lucene.document.Field;
    import org.apache.lucene.document.NumericField;
    import org.apache.lucene.index.CorruptIndexException;
    import org.apache.lucene.index.IndexWriter;
    import org.apache.lucene.index.IndexWriterConfig;
    import org.apache.lucene.store.Directory;
    import org.apache.lucene.store.FSDirectory;
    import org.apache.lucene.store.LockObtainFailedException;
    import org.apache.lucene.util.Version;
    import org.wltea.analyzer.lucene.IKAnalyzer;
    
    public class FileIndexUtils {
    	private static Directory directory = null;
    	private static Analyzer analyzer = new IKAnalyzer();
    	public static void main(String[] args) {
    		index(true);
    	}
    	static{
    		try {
    			directory = FSDirectory.open(new File("D:\\Workspaces\\customscore\\index"));
    		} catch (IOException e) {
    			e.printStackTrace();
    		}
    	}
    	
    	public static Directory getDirectory() {
    		return directory;
    	}
    	
    	public static void index(boolean hasNew) {
    		IndexWriter writer = null;
    		try {
    			writer = new IndexWriter(directory, new IndexWriterConfig(Version.LUCENE_35, analyzer));
    			if(hasNew) {
    				writer.deleteAll();
    			}
    			File file = new File("D:\\Workspaces\\customscore\\resource");
    			Document doc = null;
    			for(File f:file.listFiles()) {
    				doc = new Document();
    				doc.add(new Field("content",FileUtils.readFileToString(f),Field.Store.YES,Field.Index.ANALYZED));
    				doc.add(new Field("filename",f.getName(),Field.Store.YES,Field.Index.ANALYZED));
    				doc.add(new Field("classid","5312",Field.Store.YES,Field.Index.ANALYZED));
    				doc.add(new Field("path",f.getAbsolutePath(),Field.Store.YES,Field.Index.ANALYZED));
    				doc.add(new NumericField("date",Field.Store.YES,true).setLongValue(f.lastModified()));
    				doc.add(new NumericField("size",Field.Store.YES,true).setIntValue((int)(f.length())));
    				writer.addDocument(doc);
    			}
    		} catch (CorruptIndexException e) {
    			e.printStackTrace();
    		} catch (LockObtainFailedException e) {
    			e.printStackTrace();
    		} catch (IOException e) {
    			e.printStackTrace();
    		} finally {
    			try {
    				if(writer!=null) writer.close();
    			} catch (CorruptIndexException e) {
    				e.printStackTrace();
    			} catch (IOException e) {
    				e.printStackTrace();
    			}
    		}
    	}
    }

工程下载路径： [http://download.csdn.net/detail/wxwzy738/5320772][http_download.csdn.net_detail_wxwzy738_5320772]

[20130501213737502]: /images/20220301/1e7aa879807047d9b0199281a01e3a20.png
[http_download.csdn.net_detail_wxwzy738_5320772]: http://download.csdn.net/detail/wxwzy738/5320772