to identify internet connection

[sachin kataria]

hi,
in my application, i have to identify that system (computer) is connected to internet or not..

i try URL class but that is giving my exception:

java.net.UnknownHostException: www.google.com

i also give proxy settings using command,
java -Dhttp.proxyHost=linuxserver test

but that is giving me exception...

so, how i can identify that internet connection is there or not ....??

pls help me.

[Chengwei Lee]

Check out these codes.