Meaning in this Line

Im creating an Itemized Map Overlay for my map used in an app im creating. In a tutorial that I am following it uses the following lines:

public class CustomItemizedOverlay extends ItemizedOverlay<OverlayItem>
{
...
private ArrayList<OverlayItem> mapOverlays = new ArrayList<OverlayItem>();
...
}

My question is this; what does the brackets par开发者_开发知识库t actually mean? It that passed as a parameter to the ItemizedOverlay class? Does the <> brackets actually mean 'instanceof'? Im just looking for a-bit of clarity and understanding of the code Im trying to use so I can manipulate it better later.

Cheers

Brackets < and > are used for generic types, see page for more details.

ArrayList < T > is a generic class that can be an array list over various classes.

ArrayList < OverlayItem > is an array list over OverlayItem