It's my first time coming across such pattern of code, it might be fairly familiar to advanced gurus out there:
public static class Myclass{
public static class myChildClass{
public int a =1; //this doesn't give an error although I expected it should be declared static
}
}
I can't instantiate the static inner class and I can't access the variable int a outside the class, so does this variable become private to the class? Why does java allow this instead of complaining it be declared static?
I can't instantiate the static inner class
Of course you can:
Myclass.myChildclass m = new Myclass.myChildclass();
and I can't access the variable int a outside the class
Yes you can:
System.out.println(m.a);
so does this variable become private to the class?
No, because it's not private.
Why does java allow this instead of complaining it be declared static?
I think you misunderstand what a static class is: it's merely a nested class without an implicit reference to an instance of the enclosing class that created it. There is no requirement for its members to be static.