我写的一个简单的聊天程序（加传送文件）

package javanet; import java.awt.*; import javax.swing.*; import javax.swing.DefaultComboBoxModel; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.net.*; import java.io.*; import java.awt.event.KeyEvent; import java.awt.event.KeyAdapter; import java.awt.event.WindowEvent; import java.awt.event.WindowAdapter; public class Talk extends JFrame implements Runnable{ JOptionPane prompt=new JOptionPane(); DatagramSocket socket; DatagramPacket packet; DatagramSocket sendsocket; byte buf[]=new byte[512]; InetAddress addr=null; String words; DefaultComboBoxModel model=new DefaultComboBoxModel(); JScrollPane jScrollPane1 = new JScrollPane(); JTextArea jTextArea1 = new JTextArea(); JScrollPane jScrollPane2 = new JScrollPane(); JTextArea jTextArea2 = new JTextArea(); JLabel jLabel1 = new JLabel(); ImageIcon icon=new ImageIcon(Talk.class.getResource("1.jpg")); JButton jButton1 = new JButton(); JButton jButton2 = new JButton(); JComboBox jComboBox1 = new JComboBox(); Object tempaddr; int i=0; JLabel jLabel2 = new JLabel(); boolean flag=true; public Talk() { try { jbInit(); } catch(BindException er){prompt.showMessageDialog(this,"端口被占用,不用开启服务","错误",0);jButton1.setEnabled(false);} catch (Exception exception) { exception.printStackTrace(); } } private void jbInit() throws Exception { setSize(new Dimension(410,370)); this.addWindowListener(new Talk_this_windowAdapter(this)); getContentPane().setLayout(null); jScrollPane1.setBounds(new Rectangle(20, 10, 360, 140)); jTextArea1.setEditable(false); jScrollPane2.setBounds(new Rectangle(20, 180, 360, 100)); jTextArea2.setText(""); jTextArea2.addKeyListener(new Talk_jTextArea2_keyAdapter(this)); jLabel1.setIcon(icon); jLabel1.setBounds(new Rectangle(0, 150, 410, 30)); jButton1.setBounds(new Rectangle(223, 291, 67, 29)); jButton1.setFont(new java.awt.Font("Dialog", Font.BOLD, 14)); jButton1.setText("发送"); jButton1.addActionListener(new Talk_jButton1_actionAdapter(this)); jButton2.setBounds(new Rectangle(303, 291, 67, 29)); jButton2.setFont(new java.awt.Font("Dialog", Font.BOLD, 14)); jButton2.setText("关闭"); jButton2.addActionListener(new Talk_jButton2_actionAdapter(this)); jComboBox1.setEditable(true); jComboBox1.setBounds(new Rectangle(86, 291, 91, 29)); jComboBox1.setModel(model); jLabel2.setFont(new java.awt.Font("Dialog", Font.PLAIN, 13)); jLabel2.setText("发送地址:"); jLabel2.setBounds(new Rectangle(24, 291, 60, 29)); this.getContentPane().add(jScrollPane1); this.getContentPane().add(jScrollPane2); this.getContentPane().add(jLabel1); this.getContentPane().add(jButton2); this.getContentPane().add(jButton1); this.getContentPane().add(jLabel2); this.getContentPane().add(jComboBox1); jScrollPane2.getViewport().add(jTextArea2); jScrollPane1.getViewport().add(jTextArea1); jScrollPane1.setWheelScrollingEnabled(true); jScrollPane1.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED ); socket=new DatagramSocket(8181); new Thread(this).start(); this.setResizable(false); setTitle("Press the KeyBoard,let the world listen to your voice!"); Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); Dimension frameSize = this.getSize(); if (frameSize.height > screenSize.height) { frameSize.height = screenSize.height; } if (frameSize.width > screenSize.width) { frameSize.width = screenSize.width; } this.setLocation( (screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2); } public void run() { while(flag) { try { jTextArea2.grabFocus(); packet = new DatagramPacket(buf, buf.length); socket.receive(packet); tempaddr=packet.getAddress().toString(); jTextArea1.setText(jTextArea1.getText()+"\n"+new getTime().time+" "+tempaddr+"对你说:\n"+new String(packet.getData())); if(model.getIndexOf(tempaddr)==-1) { model.addElement(tempaddr.toString().replaceAll("/","")); setTitle("新用户"+tempaddr+"向你发来消息"); } } catch (IOException ex) {} } } public void send() { try { addr=InetAddress.getByName(jComboBox1.getSelectedItem().toString()); words=jTextArea2.getText(); if(words.length()==0){return;} sendsocket = new DatagramSocket(); packet=new DatagramPacket(words.getBytes(),words.getBytes().length,addr,8181); sendsocket.send(packet); jTextArea2.setText(""); jTextArea1.setText(jTextArea1.getText()+"\n"+new getTime().time+" "+"你对 "+addr+"说:\n"+words); } catch (Exception ex) {prompt.showMessageDialog(this,"未能发送消息到指定主机","发送失败",0);} } public void jButton1_actionPerformed(ActionEvent e) { send(); } public void jButton2_actionPerformed(ActionEvent e) { flag=false; this.dispose(); try{socket.close();}catch(Exception er){} } public void jTextArea2_keyPressed(KeyEvent e) { if (e.isShiftDown() && e.getKeyCode() == KeyEvent.VK_ENTER) { send(); } } public void this_windowClosing(WindowEvent e) { jButton2_actionPerformed((ActionEvent)jButton2.getAction()); } } class Talk_this_windowAdapter extends WindowAdapter { private Talk adaptee; Talk_this_windowAdapter(Talk adaptee) { this.adaptee = adaptee; } public void windowClosing(WindowEvent e) { adaptee.this_windowClosing(e); } } class Talk_jTextArea2_keyAdapter extends KeyAdapter { private Talk adaptee; Talk_jTextArea2_keyAdapter(Talk adaptee) { this.adaptee = adaptee; } public void keyPressed(KeyEvent e) { adaptee.jTextArea2_keyPressed(e); } } class Talk_jButton2_actionAdapter implements ActionListener { private Talk adaptee; Talk_jButton2_actionAdapter(Talk adaptee) { this.adaptee = adaptee; } public void actionPerformed(ActionEvent e) { adaptee.jButton2_actionPerformed(e); } } class Talk_jButton1_actionAdapter implements ActionListener { private Talk adaptee; Talk_jButton1_actionAdapter(Talk adaptee) { this.adaptee = adaptee; } public void actionPerformed(ActionEvent e) { adaptee.jButton1_actionPerformed(e); } }