I am facing some challenges in Eclipse please help me. from last 5 years I am using visual studio but due to my academic requirement I am learning java and recently I installed eclipse in my machine and when I am modifying some code and trying to execute the test case, eclipse throwing classnotfoundexception. In visual studio, I used to rebuild or build it but here I am not able to find anything like that. attached images of the exception.
P.S. I did google it before asking question here but did not got any solution for my problem.