Using int as a type parameter for java.util.Dictionary

Question

When I try to declare a Dictionary as such:

private Dictionary map;

The compiler gives me the following error:

Answer 1

Java collections only allow references not primitives. You need to use the wrapper classes (in this case java.lang.Integer) to do what you are after:

private Dictionary map;

they you can do things like:

int foo = map.get("hello");

and

map.put("world", 42);

and Java uses autoboxing/unboxing to deal with the details of the conversion for you.

Here is a little description on it.