一个最简单的 RPC 程序

一个最简单的 RPC 程序.

Service 接口

public interface Service {
	String sayHello(String name);
	
	String sayJoke();
}

Service 实现类

public class ServiceImpl implements Service {
	@Override
	public String sayHello(String name) {
		return "Hello " + name;
	}

	@Override
	public String sayJoke() {
		return "一姐姐半夜打黑车回家,开了后门后,想还是记下车牌吧,于是关门绕到车位看了一眼,结果车开跑了。姐姐心想司机心虚了,还好没坐这车。于是继续等,十分钟后,那黑车又绕回来停在姐姐身边摇下车窗说：你怎么没上来啊,我听关车门以为你上来了,问你去哪儿,一回头没人,这大半夜的吓死我了...(转)";
	}
}

Server 端

@SuppressWarnings("rawtypes")
public class Server {

	private final Logger logger = LoggerFactory.getLogger(Server.class);

	private final Map<Class, Object> serviceMap = new ConcurrentHashMap<>();

	public void start(int port) {
		ServerRunnable pr = new ServerRunnable(port);
		pr.start();
		logger.info("Publisher start!");
	}

	public <T> void publishService(Class<T> service, T impl) {
		serviceMap.put(service, impl);
	}

	private class ServerRunnable extends Thread {

		private int port;
		private ServerSocket ss = null;

		public ServerRunnable(int port) {
			this.port = port;
		}

		@Override
		public void run() {

			try {
				ss = new ServerSocket(port);
			} catch (IOException e) {
				logger.error("", e);
			}

			while (true) {
				Socket s = null;
				try {
					logger.info("accept");
					s = ss.accept();
				} catch (IOException e) {
					logger.error("", e);
				}

				ServerHandler handler = new ServerHandler(s, serviceMap);
				handler.start();
			}
		}
	}

	private class ServerHandler extends Thread {

		private Socket s;

		public ServerHandler(Socket s, Map<Class, Object> serviceMap) {
			this.s = s;
		}

		@Override
		public void run() {

			ObjectInputStream ois = null;
			ObjectOutputStream oos = null;
			try {
				// 主要的逻辑在这了,
				ois = new ObjectInputStream(s.getInputStream());
				Class service = (Class) ois.readObject();
				Object serviceImpl = serviceMap.get(service);
				if (serviceImpl != null) {
					String methodName = ois.readUTF();
					Class[] parameterTypes = (Class[]) ois.readObject();
					Object[] args = (Object[]) ois.readObject();

					Method method = serviceImpl.getClass().getMethod(methodName, parameterTypes);
					Object result = method.invoke(serviceImpl, args);

					oos = new ObjectOutputStream(s.getOutputStream());
					oos.writeObject(result);
					oos.flush();
					logger.info("RPC handle finish");
				} else {
					logger.warn("Service implement not found!");
				}

			} catch (Exception e) {
				logger.error("", e);
			} finally {
				if (ois != null) {
					try {
						ois.close();
					} catch (IOException e) {
					}
				}

				if (oos != null) {
					try {
						oos.close();
					} catch (IOException e) {
					}
				}

				if (s != null) {
					try {
						s.close();
					} catch (IOException e) {
					}
				}
			}
		}
	}

	public static void main(String[] args) {
		Server server = new Server();
		server.start(10001);
		server.publishService(Service.class, new ServiceImpl());
	}
}

Client 端

public class Client {

	private static final Logger logger = LoggerFactory.getLogger(Client.class);

	@SuppressWarnings("unchecked")
	public <T> T getProxy(final String host, final int port, Class<T> service) {

		InvocationHandlerImpl<T> handler = new InvocationHandlerImpl<T>(service, host, port);
		Object proxy = Proxy.newProxyInstance(this.getClass().getClassLoader(), new Class[] { Service.class }, handler);

		return (T) proxy;
	}

	private class InvocationHandlerImpl<T> implements InvocationHandler {

		private Class<T> service;
		private String host;
		private int port;

		public InvocationHandlerImpl(Class<T> service, String host, int port) {
			super();
			this.service = service;
			this.host = host;
			this.port = port;
		}

		@Override
		public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
			Socket s = null;
			ObjectInputStream ois = null;
			ObjectOutputStream oos = null;
			try {
				s = new Socket(host, port);
				oos = new ObjectOutputStream(s.getOutputStream());
				oos.writeObject(service);
				oos.writeUTF(method.getName());
				oos.writeObject(method.getParameterTypes());
				oos.writeObject(args);
				oos.flush();

				ois = new ObjectInputStream(s.getInputStream());
				return ois.readObject();
			} catch (Exception e) {
				logger.error("", e);
				return null;
			} finally {
				if (ois != null) {
					try {
						ois.close();
					} catch (IOException e) {
					}
				}
				if (oos != null) {
					try {
						oos.close();
					} catch (IOException e) {
					}
				}
				if (s != null) {
					try {
						s.close();
					} catch (IOException e) {
					}
				}
			}
		}
	}

	public static void main(String[] args) {
		Client c = new Client();
		Service service = c.getProxy("localhost", 10001, Service.class);

		System.out.println( service.sayHello("World"));
		System.out.println( service.sayJoke());

	}
}