Java通过Socket和动态代理实现简易RPC框架

本文转自Dubbo作者梁飞大神的CSDN(https://javatar.iteye.com/blog/1123915),代码简洁,五脏俱全.

1.首先实现RpcFramework,实现服务的暴露与引用功能.

 package com.zxd.dubbo.learning.rpc.framework;

 import java.io.IOException;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.lang.reflect.InvocationHandler;
 import java.lang.reflect.Method;
 import java.lang.reflect.Proxy;
 import java.net.ServerSocket;
 import java.net.Socket;

 /**
  * @Project DubboLearning
  * @Package com.zxd.dubbo.learning.rpc.framework
  * @Author：zouxiaodong
  * @Description:
  * @Date:Created in 14:32 2018/10/24.
  */
 public class RpcFramework {

     /**
      * @FileName RpcFramework.java
      * @ClassName RpcFramework
      * @MethodName export
      * @Desc 暴露服务
      * @author zouxiaodong
      * @date 2018/10/24 15:06
      * @Params [service 服务实现, port 服务端口]
      * @return void
      */
     public static void export(final Object service,int port) throws IOException {
         if(service == null){
             throw new IllegalArgumentException("service instance == null");
         }
         if(port < 0 || port > 65535){
             throw new IllegalArgumentException("Invalid port " + port);
         }
         System.out.println("Export service :" + service.getClass().getName() + " on port " + port);
         ServerSocket serverSocket = new ServerSocket(port);
         while (true){
             try {
                 final Socket socket = serverSocket.accept();
                 new Thread(new Runnable() {
                     @Override
                     public void run() {
                         ObjectInputStream input = null;
                         ObjectOutputStream output = null;
                         try {
                             input = new ObjectInputStream(socket.getInputStream());
                             String methodName = input.readUTF();
                             Class<?>[] parameterTypes = (Class<?>[]) input.readObject();
                             Object[] arguments = (Object[]) input.readObject();
                             output = new ObjectOutputStream(socket.getOutputStream());
                             Method method = service.getClass().getMethod(methodName,parameterTypes);
                             Object result = method.invoke(service,arguments);
                             output.writeObject(result);
                         } catch (Exception e) {
                             System.err.println("1."+e.getMessage());
                         }finally {
                             try {
                                 if(output != null){
                                     output.close();
                                 }
                                 if(input != null){
                                     input.close();
                                 }
                                 if(socket != null){
                                     socket.close();
                                 }
                             } catch (IOException e) {
                                 System.err.println("2."+e.getMessage());
                             }
                         }
                     }
                 }).start();
             }catch (Exception e){

             }
         }
     }

     /**
      * @FileName RpcFramework.java
      * @ClassName RpcFramework
      * @MethodName refer
      * @Desc 引用服务
      * @author zouxiaodong
      * @date 2018/10/24 15:32
      * @Params [interfaceClass 接口类型, host 服务器主机名, port 服务器端口]
      * @return T 远程服务
      */
     public static <T> T refer(final Class<T> interfaceClass,final String host,final int port){
         if(interfaceClass == null){
             throw new IllegalArgumentException("Interface class == null");
         }
         if(!interfaceClass.isInterface()){
             throw new IllegalArgumentException("The " + interfaceClass.getName() + " must be interface class!");
         }
         if (host == null || host.length() == 0) {
             throw new IllegalArgumentException("Host == null!");
         }
         if (port <= 0 || port > 65535) {
             throw new IllegalArgumentException("Invalid port " + port);
         }
         System.out.println("Get remote service " + interfaceClass.getName() + " from server " + host + ":" + port);
         return (T)Proxy.newProxyInstance(interfaceClass.getClassLoader(), new Class<?>[]{interfaceClass}, new InvocationHandler() {
             @Override
             public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                 Socket socket = new Socket(host,port);
                 ObjectOutputStream output = new ObjectOutputStream(socket.getOutputStream());
                 output.writeUTF(method.getName());
                 output.writeObject(method.getParameterTypes());
                 output.writeObject(args);
                 ObjectInputStream input = new ObjectInputStream(socket.getInputStream());
                 try {
                     Object result = input.readObject();
                     if(result instanceof Throwable){
                         throw  (Throwable)result;
                     }
                     return result;
                 }finally {
                     input.close();
                     output.close();
                     socket.close();
                 }
             }
         });
     }
 }

2.编写接口HelloService.java与实现类HelloServiceImpl.java

 package com.zxd.dubbo.learning.rpc.framework;

 /**
  * @Project DubboLearning
  * @Package com.zxd.dubbo.learning.rpc.framework.api
  * @Author：zouxiaodong
  * @Description:
  * @Date:Created in 15:50 2018/10/24.
  */
 public interface HelloService {
     String hello(String name);
 }

 package com.zxd.dubbo.learning.rpc.framework;

 /**
  * @Project DubboLearning
  * @Package com.zxd.dubbo.learning.rpc.framework.impl
  * @Author：zouxiaodong
  * @Description:
  * @Date:Created in 15:51 2018/10/24.
  */
 public class HelloServiceImpl implements HelloService {
     @Override
     public String hello(String name) {
         return "Hello "+name;
     }
 }

3.编写提供者(暴露服务)

 package com.zxd.dubbo.learning.rpc.framework;

 import java.io.IOException;

 /**
  * @Project DubboLearning
  * @Package com.zxd.dubbo.learning.rpc.framework
  * @Author：zouxiaodong
  * @Description:
  * @Date:Created in 15:54 2018/10/24.
  */
 public class RpcProvider {
     public static void main(String[] args) throws IOException {
         HelloService helloService = new HelloServiceImpl();
         RpcFramework.export(helloService,12345);
     }
 }

4.编写消费者(引用服务)

 package com.zxd.dubbo.learning.rpc.framework;

 /**
  * @Project DubboLearning
  * @Package com.zxd.dubbo.learning.rpc.framework
  * @Author：zouxiaodong
  * @Description:
  * @Date:Created in 15:55 2018/10/24.
  */
 public class RpcConsumer {
     public static void main(String[] args){
         HelloService helloService = RpcFramework.refer(HelloService.class,"127.0.0.1",12345);
         String result = helloService.hello("CoderZZ");
         System.out.println(result);
     }
 }