This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
This forum is for career questions. You are in the right place!
Why Java specifically? Some programming/scripting language will be helpful. Different tools use different languages. When Java developers automate testing, we tend to use Selenium or another tool with Java integration. When a QA show uses automation for testing, they use tools like QTP or TestComplete. I think your best bet is to see if you can automate some of the manual tests you are doing now. Even if it means offering to do it in your free time or as a side project. Or automate testing something public to get experience with a tool. Once you've worked with one automation language/tool, it will be easier to use others.