TCP的RPC

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RPC就是远程方法调用(Remote Process Call ),包含了客户端和服务端，涉及了对象的序列化传输。

1.服务端启动，注册远程调用的类
2.客户端发送请求信息包含类、方法、参数的一些信息、序列化传输
3.服务端获取信息然后执行，并返回结果，序列化返回执行结果

动态代理 序列化和反序列化

 public  class ServiceTask implements Runnable {
        Socket clent = null;
 
        public ServiceTask(Socket client) {
            this.clent = client;
        }
 
        public void run() {
            ObjectInputStream input = null;
            ObjectOutputStream output = null;
            try {
                // 2.将客户端发送的码流反序列化成对象，反射调用服务实现者，获取执行结果
                input = new ObjectInputStream(clent.getInputStream());
                String serviceName = input.readUTF();
                String methodName = input.readUTF();
                Class<?>[] parameterTypes = (Class<?>[]) input.readObject();
                Object[] arguments = (Object[]) input.readObject();
                Class serviceClass = serviceRegistry.get(serviceName);
                if (serviceClass == null) {
                    throw new ClassNotFoundException(serviceName + " not found");
                }
                Method method = serviceClass.getMethod(methodName, parameterTypes);
                Object result = method.invoke(serviceClass.newInstance(), arguments);
 
                // 3.将执行结果反序列化，通过socket发送给客户端
                output = new ObjectOutputStream(clent.getOutputStream());
                output.writeObject(result);
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (output != null) {
                    try {
                        output.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if (input != null) {
                    try {
                        input.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if (clent != null) {
                    try {
                        clent.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
 
        }
    }

public class RPCClient <T> {
    public static <T> T getRemoteProxyObj(final Class<?> serviceInterface, final InetSocketAddress addr) {
        // 1.将本地的接口调用转换成JDK的动态代理，在动态代理中实现接口的远程调用
        return (T) Proxy.newProxyInstance(serviceInterface.getClassLoader(), new Class<?>[]{serviceInterface},
                new InvocationHandler() {
                    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                        Socket socket = null;
                        ObjectOutputStream output = null;
                        ObjectInputStream input = null;
                        try {
                            // 2.创建Socket客户端，根据指定地址连接远程服务提供者
                            socket = new Socket();
                            socket.connect(addr);
 
                            // 3.将远程服务调用所需的接口类、方法名、参数列表等编码后发送给服务提供者
                            output = new ObjectOutputStream(socket.getOutputStream());
                            output.writeUTF(serviceInterface.getName());
                            output.writeUTF(method.getName());
                            output.writeObject(method.getParameterTypes());
                            output.writeObject(args);
 
                            // 4.同步阻塞等待服务器返回应答，获取应答后返回
                            input = new ObjectInputStream(socket.getInputStream());
                            return input.readObject();
                        } finally {
                            if (socket != null) socket.close();
                            if (output != null) output.close();
                            if (input != null) input.close();
                        }
                    }
                });
    }
}

public class RPCTest {
	public static void main(String[] args) throws IOException {
        new Thread(new Runnable() {
            public void run() {
                try {
                    Server serviceServer = new ServiceCenter(8088);
					//服务注册
                    serviceServer.register(SayHelloService.class, SayHelloServiceImpl.class);
                    serviceServer.start();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }).start();
		//代理模式
        SayHelloService service = RPCClient.getRemoteProxyObj(SayHelloService.class, new InetSocketAddress("localhost", 8088));
        System.out.println(service.sayHello("hello"));
    }

转载于:https://my.oschina.net/findurl/blog/1834717