In a few months I will take some android
programming courses (Java) and a part of my postgraduate course in software development is taught in Java too, so I'm thinking about starting the SL course, my question is, is Java a good language to learn with my current knowledge?, I have heard that is somewhat complex and I should be proficient in other languages before getting into Java.
All these PL courses on SL can be taken without ANY prior knowledge in programming. They are designed to kick-start beginners off, so you'll be just fine. You can check out the FAQ for more frequently asked questions.