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I think so but searching up tutorials is allways good

If you are already started with java its better to stick with it. Otherwise you might get confused between diffrent langauges. Java is easier to make games in then C++, C++ is really hard to learn....

If you want to learn about collition, look into the Rectangle clas. And for more gameprograming tutorials look at:
The Cherno - YouTube
He has some really good 2D game programming tutorials.