NestedClassesTest

NestedClassesTest

package ocp;

/** Static methods of hierarchy classes are called on the reference variable type. */
public class NestedClassTest {

	/** Nested classes need to be static in order to define static methods (Nested class, not Inner) */
	static class A {
		public void parentMethod() {
			System.out.println("parent method");
		}
		public static void someMethod() {
			System.out.println("A method");
		}
	}

	static class B extends A {
		public static void someMethod() {
			System.out.println("B method");
		}
	}

	static class C extends B {
		public static void someMethod() {
			System.out.println("C method");
		}
	}

	public static void main(String args[]) {
		C c = new C();
		c.someMethod();
		c.parentMethod();
		B b = c;
		b.someMethod();
		b.parentMethod();
		A a = b;
		a.someMethod();
		a.parentMethod();
	}
}

Output:
C method
parent method
B method
parent method
A method
parent method