Making a PLSQL call from AMImpl

Although there are various ways in which you can avoid making a PLSQL call in ADF but when working with legacy system we may need to call a procedure or function from ADF. In this post I am providing a sample method that shows how can we achieve it. Here we are trying to make a call to plsql method 'getEmployeeID' that returns employee number as string based on first name and last name.