一个简单的RPC框架

一个简单的RPC框架

实现原理：动态代理 + socket

框架代码：

package com.yunsheng.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;public class RpcFramework {    /**     * 对外暴露服务     *      * @author <a href="mailto:[e-mail]">shengyun</a>     * @since 2016年9月1日     * @param service     * @param port     * @throws Exception     */    public static void export(final Object service, int port) throws Exception {        if (null == service) {            throw new IllegalArgumentException("service is 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);        for (;;) {            // 匿名内部类只能引用外部的final变量            final Socket socket = serverSocket.accept();            new Thread(new Runnable() {                @Override                public void run() {                    ObjectInputStream ois = null;                    try {                        ois = new ObjectInputStream(socket.getInputStream());                        try {                            // 拿到入参                            String methodName = ois.readUTF();                            Class<?>[] parameterTypes = (Class<?>[]) ois.readObject();                            Object[] arguments = (Object[]) ois.readObject();                            ObjectOutputStream oos = new ObjectOutputStream(socket.getOutputStream());                            try {                                // 反射调用                                Method method = service.getClass().getMethod(methodName, parameterTypes);                                Object result = method.invoke(service, arguments);                                oos.writeObject(result);                            } catch (Exception e) {                                oos.writeObject(e);                            } finally {                                oos.close();                            }                        } catch (ClassNotFoundException e) {                            e.printStackTrace();                        }                    } catch (IOException e) {                        e.printStackTrace();                    } finally {                        if (null != ois) {                            try {                                ois.close();                            } catch (IOException e) {                                e.printStackTrace();                            }                        }                        try {                            socket.close();                        } catch (IOException e) {                            e.printStackTrace();                        }                    }                }            }).start();        }    }    /**     * 引用服务     *      * @author <a href="mailto:[e-mail]">shengyun</a>     * @since 2016年9月1日     * @param interfaceName     * @param host     * @param port     * @return     * @throws Exception     */    public static <T> T refer(final Class<T> interfaceClass, final String host, final int port) throws Exception {        if (null == interfaceClass) {            throw new Exception("interfaceClass can not be null");        }        if (!interfaceClass.isInterface()) {            throw new Exception(interfaceClass.getName() + " is not interface");        }        if (null == host || host.length() == 0) {            throw new Exception("host is null");        }        if (port < 0 || port > 65535) {            throw new Exception("invalid port");        }        System.out.println("Get remote service " + interfaceClass.getName() + "from: " + host + " " + port);        // 根据传入的接口生成动态代理类        Object instance = 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);                        try {                            ObjectOutputStream oos = new ObjectOutputStream(socket.getOutputStream());                            // 两边参数的读写必须匹配                            oos.writeUTF(method.getName());                            oos.writeObject(method.getParameterTypes());                            oos.writeObject(args);                            // 一般的动态代理代码中，我们会在invoke里调用真实对象。                            // 通过socket传递参数去执行，拿到结果                            // 这就是一个简单的rpc实现                            ObjectInputStream ois = new ObjectInputStream(socket.getInputStream());                            try {                                Object result = ois.readObject();                                if (result instanceof Throwable) {                                    throw (Throwable) result;                                }                                return result;                            } finally {                                ois.close();                                oos.close();                            }                        } finally {                            socket.close();                        }                    }                });        return (T) instance;    }}

测试代码：

package com.yunsheng.rpc.framework.test;public interface HelloService {    String Hello(String name);}

package com.yunsheng.rpc.framework.test;public class HelloServiceImpl implements HelloService {    @Override    public String Hello(String name) {        return "Hello " + name;    }}

package com.yunsheng.rpc.framework.test;import com.yunsheng.rpc.framework.RpcFramework;public class RpcProvider {    public static void main(String[] args) throws Exception {        HelloService service = new HelloServiceImpl();        RpcFramework.export(service, 1234);    }}

package com.yunsheng.rpc.framework.test;import com.yunsheng.rpc.framework.RpcFramework;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<10 ;i++)        {            String result = service.Hello("yunsheng "+ i);            System.out.println(result);            Thread.sleep(1000);        }    }}