Why doesn't Java autoboxing extend to method invocations of methods of the autoboxed types?

Question

I want to convert a primitive to a string, and I tried:

myInt.toString();

This fails with the error:

int cannot be derefere         


        

Answer 1

Java autoboxing/unboxing doesn't go to the extent to allow you to dereference a primitive, so your compiler prevents it. Your compiler still knows myInt as a primitive. There's a paper about this issue at jcp.org.

Autoboxing is mainly useful during assignment or parameter passing -- allowing you to pass a primitive as an object (or vice versa), or assign a primitive to an object (or vice versa).

So unfortunately, you would have to do it like this: (kudos Patrick, I switched to your way)

Integer.toString(myInt);