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inheritanceMystery

Author: Marty Stepp (on 2020/04/16)

Assume that the following classes have been defined: 

        public class D extends C {
            public void method1() {
                System.out.println("d 1");
            }
        }

        public class C {
            public void method1() {
                System.out.println("c 1");
            }

            public void method2() {
                System.out.println("c 2");
            }

            public String toString() {
                return "c";
            }
        }

        public class A extends C {
            public void method1() {
                System.out.println("a 1");
            }

            public String toString() {
                return "a";
            }
        }

        public class B extends A {
            public void method2() {
                System.out.println("b 2");
            }
        }

Consider the following code fragment: 

        C[] elements = {new B(), new C(), new A(), new D()};
        for (int i = 0; i < elements.length; i++) {
            System.out.println(elements[i]);
            elements[i].method1();
            elements[i].method2();
            System.out.println();
        }

What output is produced by this code? Write the output as a series of 3-line columns in order from left to right (do not label columns or rows).

elements[0]: B
elements[1]: C
elements[2]: A
elements[3]: D

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