Lucene4.10使用教程(三)：lucene的增删改查
万丈高楼平地起，在看完helloLucene的demo后，我们可以看下Lucene的增删改查，下面是详细代码。
其中：Store.YES表示将索引并且存储，Store.NO表示索引但不存储
在Lucene中使用评分来确定文档的重要度和优先级。评分越高，表示文档优先级越高，进行排序显示的时候显示的位置越靠前。在Lucene4.10中，无法对整个文档进行评分，不过可以通过对文档中各个Field的评分来提高整个文档的评分，评分可以使用doc.setBoost()来设定。
package com.johnny.lucene01.index;
import java.io.File;
import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.IntField;
import org.apache.lucene.document.LongField;
import org.apache.lucene.document.StringField;
import org.apache.lucene.document.Field.Store;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.CorruptIndexException;
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.IndexableField;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Version;
/**
* @author Johnny
* @date 2015-01-04
* @description:
* 依赖jar:Lucene-core，Lucene-analysis（使用标准分词器做测试），Lucene-queryParser
* 作用：索引操作
*/
public class IndexUtil {
private static Version Lucene_Version = Version.LUCENE_4_10_2;
private String[] ids = {"1","2","3","4","5","6"};
private String[] emails = {"[email protected]","[email protected]","[email protected]","[email protected]","[email protected]","[email protected]"};
private String[] contents = {
"welcome to visited the space,I like book",
"hello boy, I like pingpeng ball",
"my name is cc I like game",
"I like football",
"I like football and I like basketball too",
"I like movie and swim"
};
private Date[] dates = null;
private int[] attachs = {2,3,1,4,5,5};
private String[] names = {"zhangsan","lisi","john","jetty","mike","jake"};
private Directory directory = null;
private Map<String,Float> scores = new HashMap<String,Float>();
private DirectoryReader reader = null;
IndexWriter writer = null;
private void setDates() {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
try {
dates = new Date[ids.length];
dates[0] = sdf.parse("2010-02-19");
dates[1] = sdf.parse("2012-01-11");
dates[2] = sdf.parse("2011-09-19");
dates[3] = sdf.parse("2010-12-22");
dates[4] = sdf.parse("2012-01-01");
dates[5] = sdf.parse("2011-05-19");
} catch (ParseException e) {
e.printStackTrace();
}
}
//数据初始化
public IndexUtil(){
setDates();
scores.put("itat.org",2.0f);//设定评分
scores.put("zttc.edu", 1.5f);
try {
directory = FSDirectory.open(new File("/Users/ChinaMWorld/Desktop/index/"));
} catch (IOException e) {
e.printStackTrace();
}
//directory = new RAMDirectory();//创建内存索引
//index();
}
/**建立索引**/
public void index() {
IndexWriter writer = null;
try {
writer = new IndexWriter(directory,new IndexWriterConfig(Lucene_Version, new StandardAnalyzer()));
//writer.deleteAll();
Document doc = null;
for(int i=0;i<ids.length;i++) {
doc = new Document();
doc.add(new StringField("id",ids[i],Store.YES));
doc.add(new StringField("email", emails[i],Store.YES));
doc.add(new TextField("content", contents[i], Store.NO));
doc.add(new StringField("name",names[i], Store.YES));
//存储数字
doc.add(new IntField("attach",attachs[i], Store.YES));
//存储日期
doc.add(new LongField("date", dates[i].getTime(), Store.YES));
String et = emails[i].substring(emails[i].lastIndexOf("@")+1);
System.out.println(et);
/**
* 在Lucene4.x中，只能给域加权，不能给文档加权，如果要提高文档的加权，需要给
* 文档的每个域进行加权
* StringField field = new StringField("newScore", "test", Store.NO);
* field.setBoost(2.0f);//设置评分
* **/
writer.addDocument(doc);
}
} catch (IOException e) {
e.printStackTrace();
} finally{
try{
if(writer!=null) writer.close();
}catch(Exception ex){
ex.printStackTrace();
}
}
}
/***查询**/
public void query() {
try {
IndexReader reader = DirectoryReader.open(directory);;
//通过reader可以有效的获取到文档的数量
System.out.println("numDocs:"+reader.numDocs());
System.out.println("maxDocs:"+reader.maxDoc());
System.out.println("deleteDocs:"+reader.numDeletedDocs());
reader.close();
} catch (CorruptIndexException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
/**删除**/
public void delete(){
IndexWriter writer =null;
try{
writer = new IndexWriter(directory, new IndexWriterConfig(Lucene_Version, new StandardAnalyzer()));
//参数是一个选项，可以是一个Query，也可以是一个term，term是一个精确查找的值
//此时删除的文档并不会被完全删除，而是存储在一个回收站中的，可以恢复
writer.deleteDocuments(new Term("id", "1"));
writer.commit();
}catch(Exception e){
e.printStackTrace();
}finally{
try {
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**索引合并/优化**/
public void merge(){
//会将索引合并为2段，这两段中的被删除的数据会被清空
//特别注意：此处Lucene在3.5之后不建议使用，因为会消耗大量的开销，
//Lucene会根据情况自动处理的
//将多份索引合并可以使用writer.addIndexes(d1,d2);//传入各自的Diretory或者IndexReader进行合并
IndexWriter writer =null;
try{
writer = new IndexWriter(directory, new IndexWriterConfig(Lucene_Version, new StandardAnalyzer()));
writer.forceMerge(2);
}catch(Exception e){
e.printStackTrace();
}finally{
try {
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/** 强制删除 **/
public void forceDelete(){
IndexWriter writer =null;
try{
writer = new IndexWriter(directory, new IndexWriterConfig(Lucene_Version, new StandardAnalyzer()));
writer.forceMergeDeletes();
}catch(Exception e){
e.printStackTrace();
}finally{
try {
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**修改**/
public void update(){
IndexWriter writer =null;
try{
writer = new IndexWriter(directory, new IndexWriterConfig(Lucene_Version, new StandardAnalyzer()));
Document doc = new Document();
/*
* Lucene并没有提供更新，这里的更新操作其实是如下两个操作的合集
* 先删除之后再添加
*/
doc.add(new StringField("id", "21", Store.YES));
doc.add(new TextField("email", "aa.bb@s", Store.YES));
doc.add(new TextField("content", "update content like", Store.NO));
doc.add(new StringField("name", "jackson", Store.YES));
writer.updateDocument(new Term("id","1"), doc);
}catch(Exception e){
e.printStackTrace();
}finally{
try {
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**实现近实时查询，不关闭reader，但是Index有变化时，重新获取reader **/
public IndexSearcher getSearcher() {
try {
if(reader==null) {
reader = DirectoryReader.open(directory);
} else {
DirectoryReader tr = DirectoryReader.openIfChanged(reader) ;
if(tr!=null) {
reader.close();
reader = tr;
}
}
return new IndexSearcher(reader);
} catch (CorruptIndexException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
/** 查询 **/
public void search(){
try {
IndexSearcher search = getSearcher();
TermQuery query = new TermQuery(new Term("content","like"));
TopDocs tds = search.search(query, 10);
for(ScoreDoc sd:tds.scoreDocs){
Document doc = search.doc(sd.doc);
System.out.println(doc.get("id")+"---->"+
doc.get("name")+"["+doc.get("email")+"]-->"+doc.get("id")+","+
doc.get("attach")+","+doc.get("date")+"," +doc.getValues("email")[0]);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}