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.

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.