Hi
Java is really a great language, and this is very useful to any application and all new series mobile phones are java compatible so I'd encourage you to learn it.

The best way to learn how to program in Java is to find yourself some resources that can teach you the basics in a way that you'll stay engaged. I've found that trying to go through online "how-to" documentation that is published by the makers of any programming language can be very dry and doesn't really lead to learning anything unless you are extremely driven.

I have a website that's geared towards the beginner programmer (it focuses on the Java programming language) and is completely free. I've had an amazing amount of positive feedback from readers, and even some who say that this site is "the one they've been looking for".

If you're interested it can be found at http://howtoprogramwithjava.com

I also published an eBook and have started a video tutorial website, but those are both paid products and I would recommend starting with some free content to get your feet wet and see if programming is your cup of tea

Hope that helps and best of luck!

If you already know another language i think perhaps writing a game is kinda the coolest way to learn. when i was in college i knew a tiny bit of java, then our final major project came along and i wanted to program a game from scratch, so i did!
http://code.google.com/p/planetdefender/ - kinda newbie code but i think writing a game really helped me get to grips with java, i wouldn't say i'm an expert now by any stretch of the imagination and primarily i program in C++ but java was fun for my final major project (stressful at times when i encounter math problems)

I think that holds in general, the only real way of learning a programming language is to read and write code with it. It does not need to be a game, but many people consider games a fun thing to create, which thus helps in to keep coding, even when you hit rough spots.

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My project: Messing about in FreeRCT, dev blog, and IRC #freerct at oftc.net