Question

java怎么连接到elastic search集群

Answer 1

package cn.test;

import java.net.InetAddress;
import java.net.UnknownHostException;

import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.action.search.SearchType;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.InetSocketTransportAddress;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
public class ElkTest {
// private static final String CLUSTER_NAME = "cluster_name";
public static final String CLUSTER_NAME = "elasticsearch"; //实例名称
private static final String IP = "127.0.0.1";
//private static final String IP = "192.168.0.29";
private static final int PORT = 9300; //端口
//1.设置集群名称：默认是elasticsearch，并设置client.transport.sniff为true，使客户端嗅探整个集群状态，把集群中的其他机器IP加入到客户端中
/*
//对ES1.6有效
private static Settings settings = ImmutableSettings
.settingsBuilder()
.put("cluster.name",CLUSTER_NAME)
.put("client.transport.sniff", true)
.build();
*/
//对ES2.0有效
private static Settings settings = Settings
.settingsBuilder()
.put("cluster.name",CLUSTER_NAME)
.put("client.transport.sniff", true)
.build();
//创建私有对象
private static TransportClient client;

//反射机制创建单例的TransportClient对象 ES1.6版本
// static {
// try {
// Class<?> clazz = Class.forName(TransportClient.class.getName());
// Constructor<?> constructor = clazz.getDeclaredConstructor(Settings.class);
// constructor.setAccessible(true);
// client = (TransportClient) constructor.newInstance(settings);
// client.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName(IP), PORT));
// } catch (Exception e) {
// e.printStackTrace();
// }
// }

//ES2.0版本
static {
try {
client = TransportClient.builder().settings(settings).build()
.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName(IP), PORT));
} catch (UnknownHostException e) {
e.printStackTrace();
}
}

//取得实例
public static synchronized TransportClient getTransportClient(){
return client;
}

//为集群添加新的节点
public static synchronized void addNode(String name){
try {
client.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName(name),9300));
} catch (UnknownHostException e) {
e.printStackTrace();
}
}

//删除集群中的某个节点
public static synchronized void removeNode(String name){
try {
client.removeTransportAddress(new InetSocketTransportAddress(InetAddress.getByName(name),9300));
} catch (UnknownHostException e) {
e.printStackTrace();
}
}
public static void main(String args[]){
String index="logstash-2016.02.16";
String type="logs";
SearchResponse response=ElkTest.getTransportClient().prepareSearch(index)//设置要查询的索引(index)
.setSearchType(SearchType.DFS_QUERY_THEN_FETCH)
.setTypes(type)//设置type, 这个在建立索引的时候同时设置了, 或者可以使用head工具查看
.setQuery(QueryBuilders.matchQuery("message", "Accept")) //在这里"message"是要查询的field,"Accept"是要查询的内容
.setFrom(0)
.setSize(10)
.setExplain(true)
.execute()
.actionGet();
for(SearchHit hit:response.getHits()){
System.out.println(hit.getSourceAsString());
}
}
}