利用线程池技术来实现端口扫描（TCP）

// 扫描本机
 private void getLocal()
 {
  String ip = getIP();
  String portStart = txPortStart1.getText().trim();
  String portEnd = txPortEnd1.getText().trim();
  
  if (portStart.length() == 0 || portEnd.length() == 0)
   return;
  
  int s = 0;
  int e = 0;
  
  try {
   s = Integer.valueOf(portStart);
   e = Integer.valueOf(portEnd);
  } catch (Exception ex) {
   JOptionPane.showMessageDialog(null, "端口输入有误");
   return;
  } 
  
  // 检查端口是否超出范围
  if (! (checkPort(s) && checkPort(e)))
  {
   JOptionPane.showMessageDialog(null, "端口应该大于0而小于65535");
   return;
  }
  
    
  scann(ip, s, e);
  
  runThread(); // 启动线程, 监视扫描是否已完成
 }

private String getIP()
 {
  try {
   InetAddress addr = InetAddress.getLocalHost();
      return addr.getHostAddress().toString(); // ip
  }
  catch (Exception e)
  {
   JOptionPane.showMessageDialog(null, "获取IP出错!");
  }
  return null;
 }

// 扫描单个IP
 private void scann(String ip, int startPort, int endPort)
 {
  // 将所有按钮设为不可用
  setBtnEdit(false);
  status.setText("请稍候...");

  String[] add = {ip, ""};
  table.addRow(add);
  exec = Executors.newFixedThreadPool(10);
  for (int i = startPort; i <= endPort; i++)
   exec.execute(new RunSocket(ip, i));
  exec.shutdown();
    
 }