很久没写博客了，这个本为课程设计，忙完了便抽空出来与大家分享一下，以便指正错误。
1、设计一个简单的聊天室程序。采用客户/服务器模式，分为客户端程序和服务器端程序。由于服务器只能支持一个客户，实际上是一个点对点通信的程序。客户端程序和服务器程序通过网络交换聊天字符串内容，并在窗口的列表框中显示。同时，实现了文件传输系统。
2、程序主界面（包含服务器端和客户端）。
3、先后点击监听和连接按钮即可建立互联。可以发送消息或传输文件。
4、其他不多说，直接上代码部分：
服务器：
public class chatServer extends JFrame implements Runnable,ActionListener{ /** * */ private static final long serialVersionUID = -4929211394401993088L; //private static final int SERVICE_PORT=13; int SERVICE_PORT; DataInputStream in; DataOutputStream out; ServerSocket server; Socket nextClient; JTextField textField,nameField,portField; JTextArea textArea,textArea2; JButton button,fButton; JFileChooser chooser; MyradioButton lisButton,disButton; ButtonGroup group; Font font = new Font("Adobe 黑体 Std",0,16); JLabel label; public chatServer() { this.setTitle("Server"); init(); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setLayout(null); this.setBounds(0, 0, 800, 500); this.setResizable(false); //this.setLocationRelativeTo(null); //this.setUndecorated(true); this.setLocation(1000,200); this.setVisible(true); } @Override public void run(){ try{ while(true){ System.out.println("Server Start!"); if(!lisButton.isSelected()) continue; textArea.append("开始监听端口"+portField.getText()+"!\n"); SERVICE_PORT=Integer.valueOf(portField.getText()).intValue(); System.out.println("1"); server=new ServerSocket(SERVICE_PORT); System.out.println("2"); nextClient = server.accept(); textArea.append("收到并接受客户端的连接请求!\n"); in=new DataInputStream(nextClient.getInputStream()); out=new DataOutputStream(nextClient.getOutputStream()); while (true){ String strUTF=in.readUTF(); if(strUTF.equals("&&close&&")) {disButton.setSelected(true);out.writeUTF("&&close&&");break;} if(strUTF.equals("&&file.start&&")) { String fileName =in.readUTF(); chooser.setSelectedFile(new File(fileName)); int returnVal=chooser.showSaveDialog(this.getContentPane()); if(returnVal==JFileChooser.APPROVE_OPTION){ FileOutputStream fos=new FileOutputStream(chooser.getSelectedFile().getAbsolutePath()); int data; while(-1!=(data= in.readInt())) { fos.write(data); } System.out.println("文件接收完毕"); textArea.append(fileName+"接收完毕!\n"); fos.close(); } } else textArea.append(strUTF+"\n"); } in.close(); out.close(); server.close(); textArea.append("连接已断开!\n"); } }catch(Exception e){} } void init(){ Container con = this.getContentPane(); label=new JLabel(); label.setBounds(0, 0, 800, 500); button=new JButton("发送消息"); button.setFont(font); button.setBounds(670,425,110,30); button.addActionListener(this); con.add(button); fButton=new JButton("选择文件"); fButton.setFont(font); fButton.setBounds(550, 425, 110, 30); fButton.addActionListener(this); con.add(fButton); textField=new JTextField(); textField.setBounds(10,375,780,40); textField.setFont(font); textField.setOpaque(false); textField.setBorder(null); textField.addKeyListener(new KeyAdapter() { public void keyPressed(KeyEvent e) { if(e.getKeyCode()==KeyEvent.VK_ENTER){ try { out.writeUTF(textField.getText()); textField.setText(""); } catch (IOException e2) {} } } }); con.add(textField); //add nameField=new JTextField(); nameField.setBounds(235, 20, 120, 25); nameField.setText("locallhost"); nameField.setFont(font); nameField.setOpaque(false); nameField.setBorder(null); con.add(nameField); portField=new JTextField(); portField.setBounds(440, 20, 120, 25); portField.setText("1000"); portField.setFont(font); portField.setOpaque(false); portField.setBorder(null); con.add(portField); lisButton=new MyradioButton("监听"); disButton=new MyradioButton("断开"); disButton.setSelected(true); lisButton.setBounds(610, 17, 85, 30); disButton.setBounds(700, 17, 85, 30); lisButton.addActionListener(this); disButton.addActionListener(this); group = new ButtonGroup(); group.add(lisButton); group.add(disButton); con.add(lisButton); con.add(disButton); // textArea=new JTextArea(); textArea.setBounds(426, 85, 347,265); textArea.setFont(font); textArea.setEditable(false); textArea.setOpaque(false); textArea.setBorder(null); con.add(textArea); JScrollPane scrollPane = new JScrollPane(textArea); scrollPane.setOpaque(false); scrollPane.setBorder(null); scrollPane.setBounds(426, 85, 347,265); con.add(scrollPane); textArea2=new JTextArea(); textArea2.setBounds(36, 85, 347,265); textArea2.setFont(font); textArea2.setEditable(false); textArea2.setOpaque(false); textArea2.setBorder(null); con.add(textArea2); JScrollPane scrollPane2 = new JScrollPane(textArea2); scrollPane2.setOpaque(false); scrollPane2.setBorder(null); scrollPane2.setBounds(36, 85, 347,265); con.add(scrollPane2); chooser=new JFileChooser(); label.setIcon(new ImageIcon("src\\chat\\icon\\sever.png")); con.add(label); } @Override public void actionPerformed(ActionEvent e) { if(e.getSource()==button) try { out.writeUTF(textField.getText()); textArea2.append(textField.getText()+"\n"); textField.setText(""); } catch (IOException e2) {} else if (e.getSource()==fButton) { try { int returnVal=chooser.showOpenDialog(this); if(returnVal==JFileChooser.APPROVE_OPTION){ String filePath = chooser.getSelectedFile().getAbsolutePath(); String fileName = chooser.getSelectedFile().getName(); out.writeUTF("&&file.start&&"); out.writeUTF(fileName); textArea.append("开始发送"+fileName+"...\n"); FileInputStream fileInputStream=new FileInputStream(filePath); int data; while(-1!=(data=fileInputStream.read())){ out.writeInt(data); } out.writeInt(data); fileInputStream.close(); System.out.println("文件已发送完毕"); textArea.append(fileName+"发送完毕!\n"); } }catch(IOException e3){} } else if(e.getSource()==disButton) { try { out.writeUTF("&&close&&"); } catch (IOException e2) {} } } } class MyradioButton extends JRadioButton{ /** * */ private static final long serialVersionUID = 1L; public MyradioButton(String type){ super(); this.setOpaque(false); setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR)); if(type.equals("监听")){ setSelectedIcon(new ImageIcon("src\\chat\\icon\\lis_1.png")); setIcon(new ImageIcon("src\\chat\\icon\\lis_0.png")); }else if (type.equals("连接")) { setSelectedIcon(new ImageIcon("src\\chat\\icon\\con_1.png")); setIcon(new ImageIcon("src\\chat\\icon\\con_0.png")); }else if (type.equals("断开")) { setSelectedIcon(new ImageIcon("src\\chat\\icon\\dis_1.png")); setIcon(new ImageIcon("src\\chat\\icon\\dis_0.png")); } } }客户端： public class chatClient extends JFrame implements Runnable,ActionListener{ /** * */ private static final long serialVersionUID = -7103711638195532808L; //private static final int SERVICE_PORT=13; int SERVICE_PORT; DataInputStream in; DataOutputStream out; ServerSocket server; Socket socket; String hostname; JTextField textField,nameField,portField; JTextArea textArea,textArea2; JButton button,fButton; JFileChooser chooser; MyradioButton conButton,disButton; ButtonGroup group; Font font = new Font("Adobe 黑体 Std",0,16); JLabel label; public chatClient(){ this.setTitle("Client"); init(); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setLayout(null); this.setBounds(0, 0, 800, 500); this.setResizable(false); // this.setLocationRelativeTo(null); // this.setUndecorated(true); this.setLocation(200, 200); this.setVisible(true); } @Override public void run() { while(true){ try{ Thread.sleep(500); if(!conButton.isSelected()) continue; SERVICE_PORT=Integer.valueOf(portField.getText()).intValue(); //hostname=nameField.getText(); socket=new Socket(hostname,SERVICE_PORT); in=new DataInputStream(socket.getInputStream()); out=new DataOutputStream(socket.getOutputStream()); textArea.append("连接服务器成功!\n"); while(true){ String strUTF=in.readUTF(); if(strUTF.equals("&&close&&")) {disButton.setSelected(true);out.writeUTF("&&close&&");break;} if(strUTF.equals("&&file.start&&")) { String fileName =in.readUTF(); chooser.setSelectedFile(new File(fileName)); int returnVal=chooser.showSaveDialog(this.getContentPane()); if(returnVal==JFileChooser.APPROVE_OPTION){ FileOutputStream fos=new FileOutputStream(chooser.getSelectedFile().getAbsolutePath()); int data; while(-1!=(data= in.readInt())) { fos.write(data); } System.out.println("文件接收完毕"); textArea.append(fileName+"接收完毕!\n"); fos.close(); } } else textArea.append(strUTF+"\n"); } in.close(); out.close(); textArea.append("连接已断开!\n"); }catch(Exception e){} } } void init(){ Container con = this.getContentPane(); label=new JLabel(); label.setBounds(0, 0, 800, 500); button=new JButton("发送消息"); button.setFont(font); button.setBounds(670,425,110,30); button.addActionListener(this); con.add(button); fButton=new JButton("选择文件"); fButton.setFont(font); fButton.setBounds(550, 425, 110, 30); fButton.addActionListener(this); con.add(fButton); textField=new JTextField(); textField.setBounds(10,375,780,40); textField.setFont(font); textField.setOpaque(false); textField.setBorder(null); textField.addKeyListener(new KeyAdapter() { public void keyPressed(KeyEvent e) { if(e.getKeyCode()==KeyEvent.VK_ENTER){ try { out.writeUTF(textField.getText()); textField.setText(""); } catch (IOException e2) {} } } }); con.add(textField); //add nameField=new JTextField(); nameField.setBounds(235, 20, 120, 25); nameField.setText("locallhost"); nameField.setFont(font); nameField.setOpaque(false); nameField.setBorder(null); con.add(nameField); portField=new JTextField(); portField.setBounds(440, 20, 120, 25); portField.setText("1000"); portField.setFont(font); portField.setOpaque(false); portField.setBorder(null); con.add(portField); conButton=new MyradioButton("连接"); disButton=new MyradioButton("断开"); disButton.setSelected(true); conButton.setBounds(610, 17, 85, 30); disButton.setBounds(700, 17, 85, 30); conButton.addActionListener(this); disButton.addActionListener(this); group = new ButtonGroup(); group.add(conButton); group.add(disButton); con.add(conButton); con.add(disButton); // textArea=new JTextArea(); textArea.setBounds(426, 85, 347,265); textArea.setFont(font); textArea.setEditable(false); textArea.setOpaque(false); textArea.setBorder(null); con.add(textArea); JScrollPane scrollPane = new JScrollPane(textArea); scrollPane.setOpaque(false); scrollPane.setBorder(null); scrollPane.setBounds(426, 85, 347,265); con.add(scrollPane); textArea2=new JTextArea(); textArea2.setBounds(36, 85, 347,265); textArea2.setFont(font); textArea2.setEditable(false); textArea2.setOpaque(false); textArea2.setBorder(null); con.add(textArea2); JScrollPane scrollPane2 = new JScrollPane(textArea2); scrollPane2.setOpaque(false); scrollPane2.setBorder(null); scrollPane2.setBounds(36, 85, 347,265); con.add(scrollPane2); chooser=new JFileChooser(); label.setIcon(new ImageIcon("src\\chat\\icon\\client.png")); con.add(label); } @Override public void actionPerformed(ActionEvent e) { if(e.getSource()==button) try { out.writeUTF(textField.getText()); textArea2.append(textField.getText()+"\n"); textField.setText(""); } catch (IOException e2) {} else if (e.getSource()==fButton) { try { int returnVal=chooser.showOpenDialog(this); if(returnVal==JFileChooser.APPROVE_OPTION){ String filePath = chooser.getSelectedFile().getAbsolutePath(); String fileName = chooser.getSelectedFile().getName(); out.writeUTF("&&file.start&&"); out.writeUTF(fileName); textArea.append("开始发送"+fileName+"...\n"); FileInputStream fileInputStream=new FileInputStream(filePath); int data; while(-1!=(data=fileInputStream.read())){ out.writeInt(data); } out.writeInt(data); fileInputStream.close(); System.out.println("文件已发送完毕"); textArea.append(fileName+"发送完毕!\n"); } }catch(IOException e3){} } else if(e.getSource()==disButton) { try { out.writeUTF("&&close&&"); } catch (IOException e2) {} } } } 为了方便调试，main直接启用服务器和客户端两个线程： public class mainTest { public static void main(String[] args) { try { for(LookAndFeelInfo info:UIManager.getInstalledLookAndFeels()){ if("Windows".equals(info.getName())) { UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (Exception e) { // TODO: handle exception } chatServer server=new chatServer(); chatClient client=new chatClient(); new Thread(server).start(); new Thread(client).start(); } }
