【Lucene】安全过滤器，限制搜索范围（一）

安全过滤器：限制匹配范围

下面的例子里面，有两个索引文档，两者在关键字域里面都包含info项，但是每个文档属于不同的所有者；如果不使用过滤器的话，我们会搜索召两个文档。考虑到安全性，这当然不是我们想要的结果，因此我们可以使用QueryWrapperFilter将搜索空间限制在某个用于所拥有的文档范围之内。

示例代码：

package com.tan.code;

import java.io.IOException;
import java.util.logging.Filter;

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field.Store;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.QueryWrapperFilter;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Version;

public class SecurityFilterTest {

	private IndexWriter indexWriter = null;
	private IndexSearcher indexSearcher = null;

	public void securityFilter() throws IOException {
		//写入内存
		Directory directory = new RAMDirectory();
		indexWriter = new IndexWriter(directory, new IndexWriterConfig(
				Version.LUCENE_43, new StandardAnalyzer(Version.LUCENE_43)));
		Document document = new Document();

		// LiMing
		document.add(new StringField("id", "1", Store.YES));
		document.add(new TextField("owner", "LiMing", Store.YES));
		document.add(new TextField("keywords", "LiMing Info", Store.YES));
		indexWriter.addDocument(document);
		// TanWeiJie
		document = new Document();
		document.add(new StringField("id", "2", Store.YES));
		document.add(new TextField("owner", "TanWeiJie", Store.YES));
		document.add(new TextField("keywords", "TannWeiJie Info", Store.YES));
		indexWriter.addDocument(document);

		indexWriter.commit();
		indexWriter.close();
		IndexReader r = DirectoryReader.open(directory);
		indexSearcher = new IndexSearcher(r);

		// 不使用过滤器
		TermQuery termQuery = new TermQuery(new Term("keywords", "info"));
		System.out.println("不使用过滤器匹配到"
				+ indexSearcher.search(termQuery, 10).totalHits + "个结果");

		// 使用过滤器
		QueryWrapperFilter limingfilter = new QueryWrapperFilter(new TermQuery(
				new Term("owner", "liming"))); // 注意这里需要小写，使用Luke查看索引的時候就可以發現分詞器都把大寫轉換成小寫
		System.out.println("使用过滤器匹配到"
				+ indexSearcher.search(termQuery, limingfilter, 10).totalHits
				+ "个结果");

	}

}

测试代码：

	@Test
	public void test() throws IOException {
		//fail("Not yet implemented");
		SecurityFilterTest securityFilterTest=new SecurityFilterTest();
		securityFilterTest.securityFilter();
	}

输出结果：

不使用过滤器匹配到2个结果
使用过滤器匹配到1个结果

【参考《Lucene In Action》】