public class Foo {   public int a;   public Foo() { a = 3; }   public void addFive() { a += 5;} } and: public class Bar extends Foo {   public int a;   public Bar() { a = 8; }   public void addFive() { this.a += 5; } }invoked with: Foo foo = new Bar(); foo.addFive(); System.out.println("Value: " + foo.a);