Lucene学习笔记（8）-- 指定字符串开头搜索

1、创建maven项目和相关jar配置参考前面章节

2、创建写索引实例

Indexer.java

public class Indexer {


	private Integer ids[]={1,2,3};
	private String citys[]={"aingdao","banjing","changhai"};
	private String descs[]={
			"Qingdao is b beautiful city.",
			"Nanjing is c city of culture.",
			"Shanghai is d bustling city."
	};
	
	private Directory dir;
	
	/**
	 * 获取IndexWriter实例
	 * @return
	 * @throws Exception
	 */
	private IndexWriter getWriter()throws Exception{
		Analyzer analyzer=new StandardAnalyzer(); // 标准分词器
		IndexWriterConfig iwc=new IndexWriterConfig(analyzer);
		IndexWriter writer=new IndexWriter(dir, iwc);
		return writer;
	}
	
	/**
	 * 生成索引
	 * @param indexDir
	 * @throws Exception
	 */
	private void index(String indexDir)throws Exception{
		dir=FSDirectory.open(Paths.get(indexDir));
		IndexWriter writer=getWriter();
		for(int i=0;i<ids.length;i++){
			Document doc=new Document();
			doc.add(new IntField("id", ids[i], Field.Store.YES));
			doc.add(new StringField("city",citys[i],Field.Store.YES));
			doc.add(new TextField("desc", descs[i], Field.Store.YES));
			writer.addDocument(doc); // 添加文档
		}
		writer.close();
	}
	
	
	public static void main(String[] args) throws Exception {
		new Indexer().index("E:\\lucene");
	}
	
}

3、实现指定字符串开头搜索

SearchTest.java

package com.java1234.lucene;


import java.nio.file.Paths;


import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.NumericRangeQuery;
import org.apache.lucene.search.PrefixQuery;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermRangeQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.BytesRef;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;


public class SearchTest {


	private Directory dir;
	private IndexReader reader;
	private IndexSearcher is;
	
	@Before
	public void setUp() throws Exception {
		dir=FSDirectory.open(Paths.get("D:\\lucene5"));
		reader=DirectoryReader.open(dir);
		is=new IndexSearcher(reader);
	}


	@After
	public void tearDown() throws Exception {
		reader.close();
	}
	
	/**
	 * 指定字符串开头搜索
	 * @throws Exception
	 */
	@Test
	public void testPrefixQuery()throws Exception{
		PrefixQuery query=new PrefixQuery(new Term("city","a"));
		TopDocs hits=is.search(query, 10);
		for(ScoreDoc scoreDoc:hits.scoreDocs){
			Document doc=is.doc(scoreDoc.doc);
			System.out.println(doc.get("id"));
			System.out.println(doc.get("city"));
			System.out.println(doc.get("desc"));
		}	
	}
	
}