resolved this in Eclipse by clicking on Windows>Preferences>Java>Installed JREs>Edit and changing the JRE Home to C:\Program Files\Java\jdk1.7.0_10.
post back if this works.
i tried to run it. it seems there is a bug in testng plz try to change the version and run again.
Thank you Ashish the problem has been solved .. If anyone is facing the same problem here please Go to Eclipse >Help>Eclipse marketPlace> type "TestNg" in search bar then update... then go to Window>Preference>TestNG, and uncheck the "Use Project TestNg jars" >OK.