chatserver.java

java实例 本实例是初学java的人全程学习的很好辅助材料,从最简单的入门至后面可以自己开发出一个应用程序出来

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.net.*;
public class ChatServer extends JFrame implements Runnable{
  JPanel contentPane;
  JTextField txtInput = new JTextField();
  JButton btnSend = new JButton();
  List lstMsg = new List();

  /**Construct the frame*/
  public ChatServer() {
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
    ServerListen();
  }

  /**Component initialization*/
  private void jbInit() throws Exception  {
    txtInput.setText("please input here");
    txtInput.setBounds(new Rectangle(42, 234, 196, 34));
    //setIconImage(Toolkit.getDefaultToolkit().createImage(ChatServer.class.getResource("[Your Icon]")));
    contentPane = (JPanel) this.getContentPane();
    contentPane.setLayout(null);
    this.setSize(new Dimension(400, 300));
    this.setTitle("Chat Server");
    btnSend.setText("Send");
    btnSend.setBounds(new Rectangle(268, 235, 98, 35));
    btnSend.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        btnSend_actionPerformed(e);
      }
    });
    lstMsg.setBounds(new Rectangle(42, 32, 319, 192));
    contentPane.add(txtInput, null);
    contentPane.add(btnSend, null);
    contentPane.add(lstMsg, null);
  }
  /**Overridden so we can exit when window is closed*/
	protected void processWindowEvent(WindowEvent e) {
	super.processWindowEvent(e);
		if (e.getID() == WindowEvent.WINDOW_CLOSING) {
			System.exit(0);
		}
	}

    public static void main(String[] args){
	    ChatServer server = new ChatServer();
	    server.show();
    }

    public void processMsg( String str ){
        this.lstMsg.add(str);
	}

	void btnSend_actionPerformed(ActionEvent e) {
		for( int i=0; i<clients.size(); i++){
			Connection c = (Connection) clients.get(i);
			try{
				c.sendMsg( this.txtInput.getText() );
			}catch(Exception ee){}
		}
	}

    public final static int DEFAULT_PORT = 6543;
    protected ServerSocket listen_socket;
	Thread thread;
	java.util.Vector clients;

	// Create a ServerSocket to listen for connections on;  start the thread.
    public void ServerListen() {
        try {
			listen_socket = new ServerSocket(DEFAULT_PORT);
		}catch (IOException e) {
               e.printStackTrace();
         }
        processMsg("Server: listening on port " + DEFAULT_PORT);
        clients = new java.util.Vector();
 		thread = new Thread(this);
		thread.start();
    }

	// The body of the server thread.  Loop forever, listening for and
	// accepting connections from clients. For each connection,
	// create a Connection object to handle communication through the
	// new Socket.
    public void run() {
        try {
            while(true) {
                Socket client_socket = listen_socket.accept();
                Connection c = new Connection(client_socket, this);
                clients.add( c );
                processMsg( "One Client Comes in");
            }
        }catch (IOException e) {
                 e.printStackTrace();
        }
    }
}

//This class is the thread that handles all communication with a client
class Connection extends Thread {
    protected Socket client;
    protected BufferedReader in;
	protected PrintWriter out;
	ChatServer server;

    // Initialize the streams and start the thread
    public Connection(Socket client_socket, ChatServer server_frame) {
        client = client_socket;
		server = server_frame;
        try {
            in = new BufferedReader(new InputStreamReader(client.getInputStream()));
			out = new java.io.PrintWriter(client.getOutputStream());
        }
        catch (IOException e) {
            try { client.close(); } catch (IOException e2) { ; }
            e.printStackTrace();
            return;
        }
        this.start();
    }

	// Provide the service.
	// Read a line
    public void run() {
        String line;
        StringBuffer revline;
        int len;
        try {
            for(;;) {
				// read in a line
                line = receiveMsg();
				server.processMsg( line );
                if (line == null) break;
             }
        }
        catch (IOException e) { ; }
        finally { try {client.close();} catch (IOException e2) {;} }
    }

	public  void sendMsg(String msg) throws IOException{
			out.println( msg );
			out.flush();
	}

	public  String receiveMsg()  throws IOException{
		String msg = new String();
		try {

			msg = in.readLine();
		} catch(IOException e) {
              e.printStackTrace();
		}
		return msg;
	}
}