How To Test Internet Connection Using Java

It is very often required to test the internet connection for performing some operations. If there is no internet connection established, then alternative logic will be executed. Java provides useful classes in java.net package for connecting to the internet. Here I written a very simple example to test if your system is connected to internet.

If you look at the below example, I have created URL object for connecting to www.google.com . It always returns the response code 200 if there is internet connection available. Of no internet connection, it would throw and exception.

InternetConnectionExample.ajav

[code lang=”java”]
package javabeat.net.core;

import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.UnknownHostException;

public class InternetConnectionExample {
public static void main(String[] args) throws UnknownHostException,
IOException {
try {
try {
URL url = new URL("http://www.google.com");
System.out.println(url.getHost());
HttpURLConnection con = (HttpURLConnection) url
.openConnection();
con.connect();
if (con.getResponseCode() == 200){
System.out.println("Connection established!!");
}
} catch (Exception exception) {
System.out.println("No Connection");
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
[/code]