What is the role of the data types inside of < > in Java? [duplicate]

Question

Possible Duplicate:
Java Generics

To be more specific, whats the role of the <String> in the following line of code?

private List<String> item = new ArrayList<String>();

Answer 1

Mainly to allow the compiler to raise an error if you don't insert the right kind of data into the list or if you expect data of the wrong type from the list at the moment of extraction

But see the generics tutorial for an explanation: http://java.sun.com/j2se/1.5.0/docs/guide/language/generics.html