IT industry is still now growing at a notable pace. You have to be the best programmer/manager to make faster prospect. If you have selected your career path in java, my friend your work has become harder. It's my observation that most of the class A IT comapnies are saturated with Java programmers. And core Java skill is not really enough to attract attention of peers and supervisors.
So what should you learn along with core Java? I personally believe that no other language has got such a vast range of compitable platforms like Java. Starting from a micro-wave oven and mp4 players to enterprise banking systems, telephony networks - Java is used everywhere. So your first work will be to choose a correct Java platform like JAVA SE or JAVA EE. Based on your choice you can finalize which are the related technologies/tools you should learn.