Treemaps

[sandraW]

TreeMap(Integer,Integer> treeMap = new TreeMap<Integer,Integer>();

What exactly does this line of code do, casting??

[crikey]

The object "TreeMap" expects two integers as parameters. I don't have experience with TreeMap's, but with HashMaps, when you insert data into them, you place two integers to abide by the parametrized object.

[Tolls]

Nonsense.
Or at least a misunderstanding of what a Map is.

Maps (all Maps) map a Key to a Value. What that code above is doing is declaring treeMap as of type TreeMap<Integer, Integer>, the first being the class of the key and the second being the class of the value. It is also initialising it (the stuff on the right hand side).

The <..> stuff is all to do with generics.

[Lil_Aziz1]

The code above does nothing but give you a compilation error because it is a typo.

TreeMap(Integer,Integer> treeMap = new TreeMap<Integer,Integer>();

should be:

TreeMap<Integer,Integer> treeMap = new TreeMap<Integer,Integer>();

[Tolls]

Picky picky...;)