Your career choice is not between Java and Data Warehousing. Your career choice is programming. From time to time, you will be asked to do things you don’t know how to do. Learn them and do them well. If you have that attitude, your career will be sucsessful. Given the medical and social security picture, you’re about 42 years from retirement. Your chances of ending up programming in Java or on data warehouse are very small. About the same as my chances of landing another Fortran II job (thats a two in Roman numerals, not an eleven). If you want your career to last, you must be flexible.
So, what to pick now? Whichever offer looks more profitable or stable.
Datawarehousing Market is hot these days. But the problem is, DW is mostly tool based. you have many tools in DW: Informatica, DataStage, Abinitio etc. If you re choosing DW, then that means you got a chance to master one of that tool. And unlike java, you don’t have too much competitors here. If you are planning for quick money, then DW is the call.
But JAVA is JAVA. If you think for long term, then java is better choice anyway. Because program writing is something that goes better everytime you compose it. JAVA is more challenging and tough. And if you will be able to have good command in java, then it will pay you better in future.
While using a tool there will be a limit, after which you don’t have much to learn. Only the DataBase will get more complex, more number of tables, more hetrogeniety. But way to do that will always be same.
My advice, run a search in big companies Microsoft, Google, Adobe etc for the requirement of JAVA , Informatica, BO. You will get the clear picture. Try to vary the min work-ex so that you can make comparisons : if you continue with JAVA for 5 yrs, or with INFORMATICA for 5 yrs , how much will it repay you.