检测本机网络端口能不能用以下程序？

[asymmetric]

String ip="127.0.0.1";
for(int port=1;port<50;port++)
{
try{
Socket s=new Socket(ip,port);
System.out.println("端口"+port+"打开着");
s.close();
}catch(Exception e){System.out.println("端口"+port+"打开着");}
}
套接字构造函数什么情况下抛出什么异常？

[haisenmai]

好办法， ServerSocket 也可以把
我试了个 80端口 提示被使用
package csdn.dec;

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;

public class PortInUser {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
try {
ServerSocket ss = new ServerSocket(80);
} catch (IOException e) {
// TODO Auto-generated catch block
System.out.println("Port in use ");
}

try {
Socket s = new Socket("127.0.0.1",80);
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
System.out.println("ss Port in use ");
}
}

}