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前面我们也使用用到了Lucene索引库的创建和查询，发现其代码太繁琐，有太多重复代码

例如:

1.获取Directory、Analyzer、MaxFieldLength、Version对象

2.将javabean对象封转成document对象

3.将document对象封转成javabean对象

接下来我们就创建一个LuceneUtil对索引库的创建和查询进行优化

package cn.qblank.util;import java.io.File;import java.lang.reflect.Method;import org.apache.commons.beanutils.BeanUtils;import org.apache.lucene.analysis.Analyzer;import org.apache.lucene.analysis.standard.StandardAnalyzer;import org.apache.lucene.document.Document;import org.apache.lucene.document.Field;import org.apache.lucene.document.Field.Index;import org.apache.lucene.document.Field.Store;import org.apache.lucene.index.IndexWriter.MaxFieldLength;import org.apache.lucene.store.Directory;import org.apache.lucene.store.FSDirectory;import org.apache.lucene.util.Version;/** * Lucene工具类 * @author Administrator * */public class LuceneUtil {	private static Directory directory ;	private static Analyzer analyzer ; 	private static Version version; 	private static MaxFieldLength maxFieldLength;		static{		try {			directory = FSDirectory.open(new File("F:/LuceneDB"));			version = Version.LUCENE_30;			analyzer = new StandardAnalyzer(version);			maxFieldLength = MaxFieldLength.LIMITED;		} catch (Exception e) {			e.printStackTrace();		}	}		/**	 * javabean转docment	 * @param obj	 * @return	 * @throws Exception	 */	public static Document javabean2documemt(Object obj) throws Exception{		//创建document对象		Document document = new Document();		//获取字节码对象		Class clazz = obj.getClass();		//获取该对象中的私有属性: 使用强反射  这里使用类全称，防止和Lucene包起冲突		java.lang.reflect.Field[] reflectfields = clazz.getDeclaredFields();				//遍历字段		for (java.lang.reflect.Field field : reflectfields) {			//设置访问权限:因为字段是私有的			field.setAccessible(true);			String fieldName = field.getName();			//给其拼装成get方法			String methodName = "get" + fieldName.substring(0,1).toUpperCase() + fieldName.substring(1);						Method method = clazz.getMethod(methodName, null);			//调用方法			String returnValue = method.invoke(obj, null).toString();						document.add(new Field(fieldName, returnValue, Store.YES, Index.ANALYZED));		}						return document;	}		/**	 * document转javabean,可以使用BeanUtils组件	 * @throws Exception	 */	public static Object document2javabean(Document document,Class clazz) throws Exception{		//先获取字节码对象		Object obj = clazz.newInstance();		//获取到各个字段名		java.lang.reflect.Field[] reflectField = clazz.getDeclaredFields();		for (java.lang.reflect.Field field : reflectField) {			//设置访问权限			field.setAccessible(true);			//获取各个的字段名和值			String fieldName = field.getName();			String fieldValue = document.get(fieldName);			//使用BeanUtils组件封装对象			BeanUtils.setProperty(obj, fieldName, fieldValue);		}		return obj;	}			public static Directory getDirectory() {		return directory;	}	public static Analyzer getAnalyzer() {		return analyzer;	}	public static Version getVersion() {		return version;	}	public static MaxFieldLength getMaxFieldLength() {		return maxFieldLength;	}}

创建索引库优化

public void createIndexDB() throws Exception {	Article article = new Article(3, "好室友版", "好室友就是我，我就是好室友");	//将javabean封装成documment对象	Document document = LuceneUtil.javabean2documemt(article);	//创建IndexWriter对象	IndexWriter indexWriter = new IndexWriter(LuceneUtil.getDirectory(), LuceneUtil.getAnalyzer(), LuceneUtil.getMaxFieldLength());	//将document写入Lucene索引库	indexWriter.addDocument(document);	//关闭indexWriter	indexWriter.close();}

public void findIndexDB() throws Exception {	//存放封转结果对象的集合	List
   
     arrayList = new ArrayList
    
     ();	//准备输入的值	BufferedReader br = new BufferedReader(new InputStreamReader(System.in));	String keywords = br.readLine();		//创建IndexSearcher字符流对象	IndexSearcher indexSearcher = new IndexSearcher(LuceneUtil.getDirectory());	//创建QueryParser对象	QueryParser queryParser = new QueryParser(LuceneUtil.getVersion(), "content", LuceneUtil.getAnalyzer());	//封转输入的数据	Query query = queryParser.parse(keywords);	//使用indexSearcher查询前100条记录	TopDocs topDocs = indexSearcher.search(query, 100);	//迭代出词汇表中符合条件的编号	for (int i = 0; i < topDocs.scoreDocs.length; i++) {		//取出封装编号和分数的ScoreDoc对象		ScoreDoc scoreDoc = topDocs.scoreDocs[i];		//获取结果编号		int id = scoreDoc.doc;		//根据编号去原始记录表中查询对应的document对象		Document document = indexSearcher.doc(id);		//将docuement对象封转成javabean		Article article = (Article) LuceneUtil.document2javabean(document, Article.class);		//将对象添加到集合中		arrayList.add(article);	}		//遍历结果集合	for (Article article : arrayList) {		System.out.println(article);	}	//关闭indexSearcher流对象	indexSearcher.close();}
    
   

运行结果如下: