What does <ClassName> represent in Java?

I'm new to Java development and I would like to know what does this statment represent:

private A开发者_JAVA技巧rrayList<Drawable> images;

to new images ArrayList, with this Drawable something?

Thanks to all.

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These are generics. images is an ArrayList containing Drawable instances. You must always put Drawables (or subclasses of Drawable) inside the images list and you will always get Drawables back.