没想到如此简单，RPC框架几行代码就够了

Posted 2021-04-11 IT实战联盟

https://www.toutiao.com/i6796472334665384460

10分钟给你实现一个rpc，就是这么简单，来，代码走起！

/* 
 * Copyright 2011 Alibaba.com All right reserved. This software is the 
 * confidential and proprietary information of Alibaba.com ("Confidential 
 * Information"). You shall not disclose such Confidential Information and shall 
 * use it only in accordance with the terms of the license agreement you entered 
 * into with Alibaba.com. 
 */ 
package com.alibaba.study.rpc.framework; 
 
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; 
 
/** 
 * RpcFramework 
 * 
 * @author william.liangf 
 */ 
public class RpcFramework { 
 
 /** 
 * 暴露服务 
 * 
 * @param service 服务实现 
 * @param port 服务端口 
 * @throws Exception 
 */ 
 public static void export(final Object service, int port) throws Exception { 
 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 server = new ServerSocket(port); 
 for(;;) { 
 try { 
 final Socket socket = server.accept(); 
 new Thread(new Runnable() { 
 @Override 
 public void run() { 
 try { 
 try { 
 ObjectInputStream input = new ObjectInputStream(socket.getInputStream()); 
 try { 
 String methodName = input.readUTF(); 
 Class<?>[] parameterTypes = (Class<?>[])input.readObject(); 
 Object[] arguments = (Object[])input.readObject(); 
 ObjectOutputStream output = new ObjectOutputStream(socket.getOutputStream()); 
 try { 
 Method method = service.getClass().getMethod(methodName, parameterTypes); 
 Object result = method.invoke(service, arguments); 
 output.writeObject(result); 
 } catch (Throwable t) { 
 output.writeObject(t); 
 } finally { 
 output.close(); 
 } 
 } finally { 
 input.close(); 
 } 
 } finally { 
 socket.close(); 
 } 
 } catch (Exception e) { 
 e.printStackTrace(); 
 } 
 } 
 }).start(); 
 } catch (Exception e) { 
 e.printStackTrace(); 
 } 
 } 
 } 
 
 /** 
 * 引用服务 
 * 
 * @param <T> 接口泛型 
 * @param interfaceClass 接口类型 
 * @param host 服务器主机名 
 * @param port 服务器端口 
 * @return 远程服务 
 * @throws Exception 
 */ 
 @SuppressWarnings("unchecked") 
 public static <T> T refer(final Class<T> interfaceClass, final String host, final int port) throws Exception { 
 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() { 
 public Object invoke(Object proxy, Method method, Object[] arguments) throws Throwable { 
 Socket socket = new Socket(host, port); 
 try { 
 ObjectOutputStream output = new ObjectOutputStream(socket.getOutputStream()); 
 try { 
 output.writeUTF(method.getName()); 
 output.writeObject(method.getParameterTypes()); 
 output.writeObject(arguments); 
 ObjectInputStream input = new ObjectInputStream(socket.getInputStream()); 
 try { 
 Object result = input.readObject(); 
 if (result instanceof Throwable) { 
 throw (Throwable) result; 
 } 
 return result; 
 } finally { 
 input.close(); 
 } 
 } finally { 
 output.close(); 
 } 
 } finally { 
 socket.close(); 
 } 
 } 
 }); 
 } 
 
}

定义服务接口

/* 
 * Copyright 2011 Alibaba.com All right reserved. This software is the 
 * confidential and proprietary information of Alibaba.com ("Confidential 
 * Information"). You shall not disclose such Confidential Information and shall 
 * use it only in accordance with the terms of the license agreement you entered 
 * into with Alibaba.com. 
 */ 
package com.alibaba.study.rpc.test; 
 
/** 
 * HelloService 
 * 
 * @author william.liangf 
 */ 
public interface HelloService { 
 
 String hello(String name); 
 
}

实现服务

/* 
 * Copyright 2011 Alibaba.com All right reserved. This software is the 
 * confidential and proprietary information of Alibaba.com ("Confidential 
 * Information"). You shall not disclose such Confidential Information and shall 
 * use it only in accordance with the terms of the license agreement you entered 
 * into with Alibaba.com. 
 */ 
package com.alibaba.study.rpc.test; 
 
/** 
 * HelloServiceImpl 
 * 
 * @author william.liangf 
 */ 
public class HelloServiceImpl implements HelloService { 
 
 public String hello(String name) { 
 return "Hello " + name; 
 } 
 
}

暴露服务

/* 
 * Copyright 2011 Alibaba.com All right reserved. This software is the 
 * confidential and proprietary information of Alibaba.com ("Confidential 
 * Information"). You shall not disclose such Confidential Information and shall 
 * use it only in accordance with the terms of the license agreement you entered 
 * into with Alibaba.com. 
 */ 
package com.alibaba.study.rpc.test; 
 
import com.alibaba.study.rpc.framework.RpcFramework; 
 
/** 
 * RpcProvider 
 * 
 * @author william.liangf 
 */ 
public class RpcProvider { 
 
 public static void main(String[] args) throws Exception { 
 HelloService service = new HelloServiceImpl(); 
 RpcFramework.export(service, 1234); 
 } 
 
}

引用服务

/* 
 * Copyright 2011 Alibaba.com All right reserved. This software is the 
 * confidential and proprietary information of Alibaba.com ("Confidential 
 * Information"). You shall not disclose such Confidential Information and shall 
 * use it only in accordance with the terms of the license agreement you entered 
 * into with Alibaba.com. 
 */ 
package com.alibaba.study.rpc.test; 
 
import com.alibaba.study.rpc.framework.RpcFramework; 
 
/** 
 * RpcConsumer 
 * 
 * @author william.liangf 
 */ 
public class RpcConsumer { 
 
 public static void main(String[] args) throws Exception { 
 HelloService service = RpcFramework.refer(HelloService.class, "127.0.0.1", 1234); 
 for (int i = 0; i < Integer.MAX_VALUE; i ++) { 
 String hello = service.hello("World" + i); 
 System.out.println(hello); 
 Thread.sleep(1000); 
 } 
 } 
 
}

好了，代码就在这里了，是不是非常简单，大家动手试试吧！