消费者 去注册中心获取信息 然后缓存到本地 如果有生产者某个服务宕机了 会通过通知的方式告知 （订阅的方式）
微服务rpc远程调用框架中，服务的负载均衡都是采用本地负载均衡的，Spring Cloud 使用的ribbon（本地负载均衡）
如果使用Nginx，那么获取到服务信息后，请求要交给Nginx，再由Nginx进行转发实现负载均衡
本地负载均衡：本地服务从注册中心上获取服务信息列表（缓存在JVM），然后在本地使用rpc远程调用技术，比如Netty、Netty。本地负载均衡更容易实时刷新新数据。
本地效率更高呀
实现如下架构：
在玩的时候注意 不要加端口号
完整路径：/ 一定要加
pom
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.toov5.SocketForDubbo</groupId>
<artifactId>com.toov5.SocketForDubbo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>com.101tec</groupId>
<artifactId>zkclient</artifactId>
<version>0.8</version>
</dependency>
</dependencies>
</project>
服务器端
package com.toov5.SocketForDubboServer;import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;import org.I0Itec.zkclient.ZkClient;//##ServerScoekt服务端
public class ZkServerScoekt implements Runnable {
private static int port = 8080; // socket 服务启动后的所使用的 端口号
private static String parentService = "/service";
private static ZkClient zkClient = new ZkClient("192.168.91.5"); public static void main(String[] args) throws IOException {
ZkServerScoekt server = new ZkServerScoekt(port); // 构造函数传入port
regServer(); // 去zk注册
Thread thread = new Thread(server);
thread.start();
} public ZkServerScoekt(int port) {
ZkServerScoekt.port = port;
} // 注册服务
public static void regServer() {
// 先创建父节点 判断
if (!zkClient.exists(parentService)) {
// 创建父 节点
zkClient.createPersistent(parentService); // 创建父节点（持久化） } //存在就不用管了
// 创建子节点
String serverKey = parentService + "/server_" + port; // 约定了个规范
if (!zkClient.exists(serverKey)) {
zkClient.createEphemeral(serverKey, "127.0.0.1:" + port); // 临时的 上面的删除是必须的 删除一遍 在创建 保持最新的 本地获取到 进行负载均衡
} else {
zkClient.delete(serverKey);
}
} public void run() {
ServerSocket serverSocket = null;
try {
serverSocket = new ServerSocket(port);
System.out.println("Server start port:" + port);
Socket socket = null;
while (true) {
socket = serverSocket.accept();
new Thread(new ServerHandler(socket)).start();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (serverSocket != null) {
serverSocket.close();
}
} catch (Exception e2) { }
}
}}
package com.toov5.SocketForDubboServer;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;public class ServerHandler implements Runnable {
private Socket socket; public ServerHandler(Socket socket) {
this.socket = socket;
} public void run() {
BufferedReader in = null;
PrintWriter out = null;
try {
in = new BufferedReader(new InputStreamReader(this.socket.getInputStream()));
out = new PrintWriter(this.socket.getOutputStream(), true);
String body = null;
while (true) {
body = in.readLine();
if (body == null)
break;
System.out.println("Receive : " + body);
out.println("Hello, " + body);
} } catch (Exception e) {
if (in != null) {
try {
in.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
if (out != null) {
out.close();
}
if (this.socket != null) {
try {
this.socket.close();
} catch (IOException e1) {
e1.printStackTrace();
}
this.socket = null;
}
}
}
}
客户端
package com.toov5.SocketForDubboClient;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;import javax.mail.Address;import org.I0Itec.zkclient.IZkChildListener;
import org.I0Itec.zkclient.ZkClient;
import org.apache.zookeeper.data.Stat;
import org.jboss.netty.channel.StaticChannelPipeline;
import org.jboss.netty.util.internal.SystemPropertyUtil;
import org.omg.CORBA.PUBLIC_MEMBER;
import org.w3c.dom.ls.LSInput;public class ZkServerClient {
public static List<String> listServer = new ArrayList<String>();
private static ZkClient zkClient = new ZkClient("192.168.91.5");
private static String parentService = "/service"; public static void main(String[] args) {
initServer();
ZkServerClient client = new ZkServerClient();
BufferedReader console = new BufferedReader(new InputStreamReader(System.in));
while (true) {
String name;
try {
name = console.readLine();
if ("exit".equals(name)) {
System.exit(0);
}
client.send(name);
} catch (IOException e) {
e.printStackTrace();
}
}
} // 注册所有server
public static void initServer() {
// 读取所有节点 信息
List<String> children = zkClient.getChildren(parentService);
getChildren(zkClient, children);
zkClient.subscribeChildChanges(parentService, new IZkChildListener() {
public void handleChildChange(String parentPath, List<String> currentChilds) throws Exception {
System.out.println("注册中心服务列表信息有变化");
getChildren(zkClient, currentChilds);//如果监听到有变化了 就要重新读取哦
}
}); } public static void getChildren(ZkClient zkClient, List<String> children) {
listServer.clear();
for (String ch : children) {
String serverAddr = zkClient.readData(parentService + "/" + ch); // 拿到服务地址
listServer.add(serverAddr);
}
System.out.println("服务接口地址"+listServer.toString());
} // 请求总数
private static int reqCount = 1;
// //服务个数
// private static int serverCount = 0; //初始值是0 // 获取当前server信息
public static String getServer() {
int index = reqCount % listServer.size();
String address = listServer.get(index);
System.out.println("客户端请求服务器" + address);
reqCount++;
return address;
} public void send(String name) { String server = ZkServerClient.getServer();
String[] cfg = server.split(":"); Socket socket = null;
BufferedReader in = null;
PrintWriter out = null;
try {
socket = new Socket(cfg[0], Integer.parseInt(cfg[1]));
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
out = new PrintWriter(socket.getOutputStream(), true); out.println(name);
while (true) {
String resp = in.readLine();
if (resp == null)
break;
else if (resp.length() > 0) {
System.out.println("Receive : " + resp);
break;
}
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (out != null) {
out.close();
}
if (in != null) {
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
客户端去获取下面的 地址信息 就好办了：
运行结果
动态的哦
