exercise20_1server.java

这是一个基于JAVA的网络编程的例子

// Exercise20_1Server.java: The server can communicate with
// multiple clients concurrently using the multiple threads
import java.io.*;
import java.net.*;
import java.util.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Exercise20_1Server extends JFrame {
  private JTextArea jta = new JTextArea();
  public static void main(String[] args) {
    new Exercise20_1Server();
  }
  public Exercise20_1Server() {
    getContentPane().setLayout(new BorderLayout());
    getContentPane().add(new JScrollPane(jta), BorderLayout.CENTER);
    jta.setWrapStyleWord(true);
    jta.setLineWrap(true);
    setTitle("Exercise20_1Server");
    setSize(500, 300);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setVisible(true);
    try {
      ServerSocket serverSocket = new ServerSocket(8000);
      jta.append("Exercise20_1Server started at " + new Date() + '\n');
      int clientNo = 1;
      while (true) {
         Socket connectToClient = serverSocket.accept();
        jta.append("Starting thread for client " + clientNo +
          " at " + new Date() + '\n');
        InetAddress clientInetAddress =
          connectToClient.getInetAddress();
        jta.append("Client " + clientNo + "'s host name is "
          + clientInetAddress.getHostName() + "\n");
        jta.append("Client " + clientNo + "'s IP Address is "
          + clientInetAddress.getHostAddress() + "\n");
        HandleAClient thread = new HandleAClient(connectToClient);
        thread.start();
        clientNo++;
      }
    }
    catch(IOException ex) {
      System.err.println(ex);
    }
  }
  class HandleAClient extends Thread {
    private Socket connectToClient;
    public HandleAClient(Socket socket) {
      connectToClient = socket;
    }
    public void run() {
      try {
        DataInputStream isFromClient = new DataInputStream(
          connectToClient.getInputStream());
        DataOutputStream osToClient = new DataOutputStream(
          connectToClient.getOutputStream());
        while (true) {
          double length = isFromClient.readDouble();
          double width = isFromClient.readDouble();
          double high = isFromClient.readDouble();
          double area = 2*((length * width)+(width * high)+(high * length));
          double volume = length * width * high;
          osToClient.writeDouble(area);
          osToClient.writeDouble(volume);
          jta.append("Length: " + length +
            " Width: " + width + " High: " +
            high + "\n");
          jta.append(" Area: " + area + " " +
            " Volume: " + volume + '\n');
        }
      }
      catch(IOException e) {
        System.err.println(e);
      }
    }
  }
}