SAP ABAP is a nice language. You do not really need java or .net skills in abap. But you do need sql for all your table operations like reading and saving to table. Web dynpro (SAP web-based applications ) can be done in both ABAP and java, so you wont struggle as in that case you will go with java. Remember that you also may need to understand your OO concepts and classes. I hope i this answers it for you.