I am using apache commons dbcp connection pooling libraries in my application.
can any body tell me whether it is any way problematic to use these libraries in my application legally , i.e in terms of license .
Does my product also becomes open when i use these libraries according to GNU public license ...
The GPL is not the same thing as the Apache license. If you're not sure of the differences, then you should really read them (and possibly start with their respective Wikipedia pages). But no - the Apache license does not force your application's source code to be open.