elasticsearch 口水篇（3）java客户端 – Jest

elasticsearch有丰富的客户端，java客户端有Jest。其原文介绍如下：

Jest is a Java HTTP Rest client for ElasticSearch.It is actively developed and tested by Searchly.

A sample Java application using Jest can be found on GitHub https://github.com/searchbox-io/java-jest-sample.

[http://www.searchly.com/documentation/developer-api-guide/java-jest/]

下面我们做一个很简单的实例，以下几个功能：

1）批量添加1000个user对象；

2）通过id进行查询；

3）通过name进行查询；

user对象定义：

package com.fox.c1;import io.searchbox.annotations.JestId;/**
 * @author huangfox
 * @date 2014年1月22日 下午5:31:52
 *
 */
public class User {
@JestId
private Long id;
private String name;
private int age;public Long getId() {
return id;
}public void setId(Long id) {
this.id = id;
}public String getName() {
return name;
}public void setName(String name) {
this.name = name;
}public int getAge() {
return age;
}public void setAge(int age) {
this.age = age;
}}

简单实现一个工厂类，用来获得JestHttpClient，如下：

package com.fox.c1;import io.searchbox.client.JestClientFactory;
import io.searchbox.client.config.HttpClientConfig;
import io.searchbox.client.http.JestHttpClient;/**
 * @author huangfox
 * @date 2014年1月22日 下午5:16:15
 *
 */
public class ESFactory {
private static JestHttpClient client;private ESFactory() {}public synchronized static JestHttpClient getClient() {
if (client == null) {
JestClientFactory factory = new JestClientFactory();
factory.setHttpClientConfig(new HttpClientConfig.Builder(
"http://localhost:9200").multiThreaded(true).build());
client = (JestHttpClient) factory.getObject();
}
return client;
}public static void main(String[] args) {
JestHttpClient client = ESFactory.getClient();
System.out.println(client.getAsyncClient());
System.out.println(client.getServers());
client.shutdownClient();
}
}

测试类：

package com.fox.c1;import io.searchbox.client.JestResult;
import io.searchbox.client.http.JestHttpClient;
import io.searchbox.core.Get;
import io.searchbox.core.Index;
import io.searchbox.core.Search;
import io.searchbox.indices.CreateIndex;
import io.searchbox.indices.DeleteIndex;import java.io.IOException;import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.builder.SearchSourceBuilder;/**
 * @author huangfox
 * @date 2014年1月22日 下午5:32:20
 *
 */
public class ESTest {private JestHttpClient client = ESFactory.getClient();/**
 * indexing
 *
 * @param indexName
 */
public void index(String indexName) {
try {
// drop
DeleteIndex dIndex = new DeleteIndex(new DeleteIndex.Builder(
indexName));
client.execute(dIndex);
// create
CreateIndex cIndex = new CreateIndex(new CreateIndex.Builder(
indexName));
client.execute(cIndex);
// add doc
for (int i = 0; i < 1000; i++) {User user = new User();
user.setId(new Long(i));
user.setName("huang fox " + i);
user.setAge(i % 100);
Index index = new Index.Builder(user).index(indexName)
.type(indexName).build();
client.execute(index);
}
//
client.shutdownClient();
} catch (IOException e) {
e.printStackTrace();
}
}/**
 * getting by id
 *
 * @param indexName
 * @param query
 */
public void get(String indexName, String query) {
Get get = new Get.Builder(indexName, query).build();
try {
JestResult rs = client.execute(get);
System.out.println(rs.getJsonString());
//
client.shutdownClient();
} catch (IOException e) {
e.printStackTrace();
}
}/**
 * query
 *
 * @param query
 */
public void search(String query) {
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
searchSourceBuilder.query(QueryBuilders.queryString(query));
searchSourceBuilder.field("name");
Search search = new Search.Builder(searchSourceBuilder.toString())
.build();
try {
JestResult rs = client.execute(search);
System.out.println(rs.getJsonString());
//
client.shutdownClient();
} catch (IOException e) {
e.printStackTrace();
}
}public static void main(String[] args) {
ESTest t = new ESTest();
String indexName = "user";
// indexing
t.index(indexName);
// getting by id
t.get(indexName, "2");
// query
String query = "fox";
t.search(query);
}}

index 批量添加建议使用bulk，效率高(减少通讯次数)：

public void indexBulk(String indexName) {
try {
// drop
DeleteIndex dIndex = new DeleteIndex(new DeleteIndex.Builder(
indexName));
client.execute(dIndex);
// create
CreateIndex cIndex = new CreateIndex(new CreateIndex.Builder(
indexName));
client.execute(cIndex);
// add doc
Bulk.Builder bulkBuilder = new Bulk.Builder();
for (int i = 0; i < 1000; i++) {User user = new User();
user.setId(new Long(i));
user.setName("huang fox " + i);
user.setAge(i % 100);
Index index = new Index.Builder(user).index(indexName)
.type(indexName).build();
bulkBuilder.addAction(index);
}
client.execute(bulkBuilder.build());
//
client.shutdownClient();
} catch (IOException e) {
e.printStackTrace();
}
}