// polymorphism/Frog.java // (c)2016 MindView LLC: see Copyright.txt // We make no guarantees that this code is fit for any purpose. // Visit http://mindviewinc.com/Books/OnJava/ for more book information. // Cleanup and inheritance // {java polymorphism.Frog} package polymorphism; class Characteristic { private String s; Characteristic(String s) { this.s = s; System.out.println("Creating Characteristic " + s); } protected void dispose() { System.out.println("disposing Characteristic " + s); } } class Description { private String s; Description(String s) { this.s = s; System.out.println("Creating Description " + s); } protected void dispose() { System.out.println("disposing Description " + s); } } class LivingCreature { private Characteristic p = new Characteristic("is alive"); private Description t = new Description("Basic Living Creature"); LivingCreature() { System.out.println("LivingCreature()"); } protected void dispose() { System.out.println("LivingCreature dispose"); t.dispose(); p.dispose(); } } class Animal extends LivingCreature { private Characteristic p = new Characteristic("has heart"); private Description t = new Description("Animal not Vegetable"); Animal() { System.out.println("Animal()"); } @Override protected void dispose() { System.out.println("Animal dispose"); t.dispose(); p.dispose(); super.dispose(); } } class Amphibian extends Animal { private Characteristic p = new Characteristic("can live in water"); private Description t = new Description("Both water and land"); Amphibian() { System.out.println("Amphibian()"); } @Override protected void dispose() { System.out.println("Amphibian dispose"); t.dispose(); p.dispose(); super.dispose(); } } public class Frog extends Amphibian { private Characteristic p = new Characteristic("Croaks"); private Description t = new Description("Eats Bugs"); public Frog() { System.out.println("Frog()"); } @Override protected void dispose() { System.out.println("Frog dispose"); t.dispose(); p.dispose(); super.dispose(); } public static void main(String[] args) { Frog frog = new Frog(); System.out.println("Bye!"); frog.dispose(); } } /* Output: Creating Characteristic is alive Creating Description Basic Living Creature LivingCreature() Creating Characteristic has heart Creating Description Animal not Vegetable Animal() Creating Characteristic can live in water Creating Description Both water and land Amphibian() Creating Characteristic Croaks Creating Description Eats Bugs Frog() Bye! Frog dispose disposing Description Eats Bugs disposing Characteristic Croaks Amphibian dispose disposing Description Both water and land disposing Characteristic can live in water Animal dispose disposing Description Animal not Vegetable disposing Characteristic has heart LivingCreature dispose disposing Description Basic Living Creature disposing Characteristic is alive */