NullPointerException but compiling?

Question

I\'m writing a simple command line game. I\'ve got many functions and all, and will only post the essential here.

Problem: The program compiles but when levelup()<

Answer 1

You get a NullPointerException because p is null. What you've done here:

Player p = new Player(nome);

is declare a local variable p. The static class variable p is untouched, so it remains null.

This is called shadowing (JLS, Section 6.4.1):

Some declarations may be shadowed in part of their scope by another declaration of the same name, in which case a simple name cannot be used to refer to the declared entity.

...

A declaration d of a type named n shadows the declarations of any other types named n that are in scope at the point where d occurs throughout the scope of d.

Remove Player, so the reference to the static class variable p is what you want:

p = new Player(nome);