socket_server.java

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class Server {
	public static final int LISTEN_PORT = 5987;

	public void listenRequest() {
		ServerSocket serverSocket = null;
		ExecutorService threadExecutor = Executors.newCachedThreadPool();
		try {
			serverSocket = new ServerSocket(LISTEN_PORT);
			System.out.println("Server listening requests...");
			while (true) {
				Socket socket = serverSocket.accept();
				threadExecutor.execute(new RequestThread(socket));
			}
		}
		catch (IOException e) {
			e.printStackTrace();
		}
		finally {
			if (threadExecutor != null)
				threadExecutor.shutdown();
			if (serverSocket != null)
				try {
					serverSocket.close();
				}
				catch (IOException e) {
					e.printStackTrace();
				}
		}
	}

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		Server server = new Server();
		server.listenRequest();
	}

	/**
	 * 處理Client端的Request執行續。
	 */
	class RequestThread implements Runnable {
		private Socket clientSocket;

		public RequestThread(Socket clientSocket) {
			this.clientSocket = clientSocket;
		}

		/* (non-Javadoc)
		 * @see java.lang.Runnable#run()
		 */
		@Override
		public void run() {
			System.out.printf("有%s連線進來!\n", clientSocket.getRemoteSocketAddress());
			DataInputStream input = null;
			DataOutputStream output = null;

			try {
				input = new DataInputStream(this.clientSocket.getInputStream());
				output = new DataOutputStream(this.clientSocket.getOutputStream());
				while (true) {
					output.writeUTF(String.format("Hi, %s!\n", clientSocket.getRemoteSocketAddress()));
					output.flush();
					// TODO 處理IO，這邊定義protocol協定！！

					break;
				}
			}
			catch (IOException e) {
				e.printStackTrace();
			}
			finally {
				try {
					if (input != null)
						input.close();
					if (output != null)
						output.close();
					if (this.clientSocket != null && !this.clientSocket.isClosed())
						this.clientSocket.close();
				}
				catch (IOException e) {
					e.printStackTrace();
				}
			}
		}
	}
}