Does the Java ClassLoader load inner classes?

Question

If I have a inner class declaration such as:

Class A {
    public static class B {
    }
}

followed by:

Class impl         


        

Answer 1

A ClassLoader will not load a class, unless it was requested (e.g. using loadClass). While loading a class, a ClassLoader will request referenced classes.

As your class A does not reference A.B, A.B will not be loaded, whether it is static or not. (To be honest, A does reference A.B, but not in a manner causing the ClassLoader to load A.B.)

If you add a field of type A.B or use the type A.B in another way (e.g. as a method return type), it will actually be referenced in A.class and therefore be loaded.