Both are for different purposes, but I suggest if you're currently studying C++, then you might a well upgrade to Java. Java is somewhat similar to C++ and C, so if you know any of those two, you will have quite an easy time learning java. Java also takes out some of the things in C++ that often caused errors, like the pointers. Java is also platform independent, meaning it could work on any platform, unlike wherein C and C++, it basically works only in the platform you wrote it on (i.e. 32 or 64 bit).