RPC框架几行代码就够了

转自;http://javatar.iteye.com/blog/1123915

原理, 
服务器启动了一个线程监听 Socket 端口, 
有Socket访问了, 反序列化解析出
调用哪个Service 哪个 方法, 以及传入的 参数,
再用Socket 写回去.

客户端 利用 Jdk 的Proxy 生成了一个代理类,
在创建 Proxy 时建立与服务器的Socket连接.
调用 Proxy 的方法时, 向服务器发送数据, 等待结果返回.

核心就是socket和动态代理

package com.jiepu;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() {@Overridepublic 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();}}});}}

package com.jiepu;import com.jiepu.test.HelloService;import com.jiepu.test.HelloServiceImpl;//核心就是socket和动态代理public class RpcProvider {public static void main(String[] args) throws Exception {HelloService service = new HelloServiceImpl();RpcFramework.export(service, 1234);}}

package com.jiepu.client;import com.jiepu.RpcFramework;import com.jiepu.test.HelloService; 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);                        System.out.println(service.getStudent());            Thread.sleep(1000);        }    }}

package com.jiepu.test;public interface HelloService {     String hello(String name);        Student getStudent();     }

package com.jiepu.test;public interface HelloService {     String hello(String name);        Student getStudent();     }

package com.jiepu.test;public class HelloServiceImpl implements HelloService {     public String hello(String name) {        return "Hello " + name;    }@Overridepublic Student getStudent() {return new Student(120, "xxxx", "背景");} }