Checking Host Reachability/Availability in Android

Question

Ive been trying to do what i thought would be a simple reachability of host test at the beginning of my apps internet ventures, but documentation isnt helping and neither ar

Answer 1

Try this one:

boolean reachable = false;

try {
    reachable = InetAddress.getByName("www.example.com").isReachable(2000);
} catch (IOException e) {
    e.printStackTrace();
    reachable = false;
}

if (reachable) { 
    // do your work here 
} 

But this could fail even if the web server is up and running perfectly because of the way how isReachable(int timeout) is implemented:

Test whether that address is reachable. Best effort is made by the implementation to try to reach the host, but firewalls and server configuration may block requests resulting in a unreachable status while some specific ports may be accessible. A typical implementation will use ICMP ECHO REQUESTs if the privilege can be obtained, otherwise it will try to establish a TCP connection on port 7 (Echo) of the destination host.