Decorator_Pattern_Exemple

import java.util.*;
import java.lang.*;
import java.io.*;

class Ideone
{
    public interface Bolo {
        public String obterNome();
        public double obterCusto();
        public String obterIngredientes();
    }

    public static class BoloSimples implements Bolo {
        @Override
        public String obterNome() {
            return "Bolo";
        }

        @Override
        public double obterCusto() {
            return 15;
        }

        @Override
        public String obterIngredientes() {
            return "Massa de Bolo";
        }
    }

    public static abstract class BoloDecorator implements Bolo {
        protected final Bolo decBolo;

        public BoloDecorator(Bolo b) {
            this.decBolo = b;
        }

        public String obterNome() {
            return decBolo.obterNome();
        }

        public double obterCusto() {
            return decBolo.obterCusto();
        }

        public String obterIngredientes() {
            return decBolo.obterIngredientes();
        }
    }

    static class BoloChocolate extends BoloDecorator {

        public BoloChocolate(Bolo b) {
            super(b);
        }

        public String obterNome() {
            return super.obterNome() + " Chocolate";
        }

        public double obterCusto() {
            return super.obterCusto() + 3.5;
        }

        public String obterIngredientes() {
            return super.obterIngredientes() + ", Chocolate";
        }
    }

    static class BoloSprinkles extends BoloDecorator {

        public BoloSprinkles(Bolo b) {
            super(b);
        }

        public String obterNome() {
            return super.obterNome() + " Sprinkles";
        }

        public double obterCusto() {
            return super.obterCusto() + 1;
        }

        public String obterIngredientes() {
            return super.obterIngredientes() + ", Sprinkles";
        }
    }

    public static void printInfo(Bolo b) {
        System.out.println("Nome: " + b.obterNome() + "\nCusto: " + b.obterCusto() + "\nIngredientes: " + b.obterIngredientes() + "\n---------------------------");
    }

    public static void main (String[] args)
    {
        Bolo b = new BoloSimples();
        printInfo(b);

        b = new BoloChocolate(b);
        printInfo(b);

        b = new BoloSprinkles(b);
        printInfo(b);

        b = new BoloSimples();
        b = new BoloSprinkles(b);
        printInfo(b);
    }
}