判断两个服务之间是否离线

public class TelnetTest {

    @Test
    public void telnetTest(){
        long start = System.currentTimeMillis();
        boolean flag = telnet("192.1.1.132",8100,1000);
        long end = System.currentTimeMillis();

        System.out.println(flag ? "通讯正常" : "通讯异常" );
        System.out.println(String.format(" 耗时 %s ms", end - start));
    }

    private boolean telnet(String hostName, int port,int timeout){
        Socket socket = new Socket();
        boolean connected = false;
        try {
            SocketAddress address = new InetSocketAddress(hostName,port);
            socket.connect(address,timeout);
            connected = socket.isConnected();
        } catch (IOException e) {
//            System.out.println("通讯异常");
        } finally {
            try {
                socket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return connected;
    }
}