Java checking internet connection on Linux issue

Question

I need to check internet connection, so I write this small class:

import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Timer;
import java.util.TimerTask;

public class TestConnection {
    public boolean isInternetAccessed() {
        try {
            URL url = new URL("http://www.google.com");
            HttpURLConnection con = (HttpURLConnection) url.openConnection();
            con.setConnectTimeout(4000);
            con.connect();

            if (con.getResponseCode() == 200) {
                return true;
            } else {
                return false;
            }
        } catch (Exception exception) {
            System.out.println("No Connection");
            return false;
        } 
    }
    public static void main(String[] args) {
        Timer timer = new Timer();
        int period = 10000;
        timer.scheduleAtFixedRate(new TimerTask() {
            TestConnection internetCheck = new TestConnection();

            public void run() {
                try {
                    System.out.println("Starting..................");
                    System.out.println("Internet Status: " + internetCheck.isInternetAccessed());
                    System.out.println("Sleeping..................");
                } catch (Exception ex) {
                    ex.printStackTrace();
                }
            }
        }, 0, period);
    }

}

This program running fine in Java 1.7 on Window machine. But in Linux, it have problem: If I disconnect this machine from internet, and run this program, after that I connect this machine to Internet, and the program always said cannot connect.

Any help?

Answer 1

The Programs works correctly in Linux Environment too. Please check your environment issue if there is any. No problem with the code