Questions About Learning Java

So basically, I've played with the thought learning Java caused by the fact that it has become one of the most desired programming languages out there. Increasing job offers and so on.
And I feel like "that's a thing I want to do". Now, my questions to this is:

1. Do you know good ways, sources or maybe websites too, which I could use for learning?
   
2. How do I stick to the learning process without getting bored?