Regarding DOJ (Date of Joining)?
DOJ will be the first day of joining. The day you officially get integrated with wipro. Why it is getting delayed, there could be many reasons from lot internal allocation to business scope. Don’t worry abt doj. When the HR sent you a mail that you are selected for wipro and do the Medical test and blah blah blah, you got selected. The DOJ and the place to join will be intimated later. But try to explore oppurtunities in meantime on software/ testing domains which will be helpful when u enter into trainings. Now regarding trainings, It is not sure that you will be placed in the language you are taught in college. So be open for the oppurtunities. Training will be a peice of cake if you are open for oppurtunities. There is nothing called impossible so be open.