自行实现一个简易RPC框架【转载】

原文 http://javatar.iteye.com/blog/1123915

代码结构

rpc主要类 RpcFramework.java
里面有两个方法 export 和 refer
export 相当是把服务注册进来
refer 就是引用服务了

// An highlighted block
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;

/**
 * @Author:lm
 * @Despriction:
 * @Date:2018/11/1 15:57
 */
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() {

                    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();
                }
            }
        });
    }

}

业务接口 HelloService.java

package service;

/**
 * @Author:lm
 * @Despriction:
 * @Date:2018/11/1 16:00
 */

public interface HelloService {

    String hello(String name);
}

业务接口实现类 HelloServiceImpl.java

package service.impl;

import service.HelloService;

/**
 * @Author:lm
 * @Despriction:
 * @Date:2018/11/1 16:01
 */
public class HelloServiceImpl implements HelloService {

    public String hello(String name) {
        return "hello rpc:"+name;
    }
}

服务提供者 RpcProvider.java

import service.HelloService;
import service.impl.HelloServiceImpl;

/**
 * @Author:lm
 * @Despriction:
 * @Date:2018/11/1 16:08
 */
public class RpcProvider {
    public static void main(String[] args) throws Exception{
        HelloService helloService = new HelloServiceImpl();

        RpcFramework.export(helloService,3453);

    }
}

服务消费者 RpcConsumer.java

import service.HelloService;

/**
 * @Author:lm
 * @Despriction:
 * @Date:2018/11/1 16:11
 */
public class RpcConsumer {
    public static void main(String[] args) throws Exception {
        HelloService helloService = RpcFramework.refer(HelloService.class, "127.0.0.1", 3453);
        String hello = helloService.hello("World");
        System.out.println(hello);
    }
}

运行结果