1. Patrón de diseño de constructor
2. Ventaja del constructor DP
3. Uso de Builder DP
4. UML del constructor DP
5. Ejemplo de constructor DP

El patrón constructor dice que 'construir un objeto complejo a partir de objetos simples utilizando un enfoque paso a paso'

Se utiliza principalmente cuando el objeto no se puede crear en un solo paso, como en la deserialización de un objeto complejo.

Ventaja del patrón de diseño del constructor

Las principales ventajas de Builder Pattern son las siguientes:

• Proporciona una clara separación entre la construcción y la representación de un objeto.
• Proporciona un mejor control sobre el proceso de construcción.
• Admite cambiar la representación interna de los objetos.

UML para ejemplo de patrón de construcción

Ejemplo de patrón de diseño de constructor

Para crear un ejemplo simple de un patrón de diseño de constructor, debe seguir los siguientes 6 pasos.

1. Crear interfaz de embalaje
2. Crear 2 clases abstractas CD y compañía.
3. Crear 2 clases de implementación de empresa: Sony y Samsung.
4. Crear la clase CDType
5. Crear la clase CDBuilder
6. Crea la clase BuilderDemo

1) Crear interfaz de embalaje

 public interface Packing { public String pack(); public int price(); } 

2) Crear 2 CD de clases abstractas y compañía.

Cree un CD de clase abstracta que implementará la interfaz Packing.

 public abstract class CD implements Packing{ public abstract String pack(); } 

 public abstract class Company extends CD{ public abstract int price(); } 

3) Cree 2 clases de implementación de empresa: Sony y Samsung.

 public class Sony extends Company{ @Override public int price(){ return 20; } @Override public String pack(){ return 'Sony CD'; } }//End of the Sony class. 

 public class Samsung extends Company { @Override public int price(){ return 15; } @Override public String pack(){ return 'Samsung CD'; } }//End of the Samsung class. 

4) Crea la clase CDType

 import java.util.ArrayList; import java.util.List; public class CDType { private List items=new ArrayList(); public void addItem(Packing packs) { items.add(packs); } public void getCost(){ for (Packing packs : items) { packs.price(); } } public void showItems(){ for (Packing packing : items){ System.out.print('CD name : '+packing.pack()); System.out.println(', Price : '+packing.price()); } } }//End of the CDType class. 

5) Crea la clase CDBuilder

 public class CDBuilder { public CDType buildSonyCD(){ CDType cds=new CDType(); cds.addItem(new Sony()); return cds; } public CDType buildSamsungCD(){ CDType cds=new CDType(); cds.addItem(new Samsung()); return cds; } }// End of the CDBuilder class. 

6) Crea la clase BuilderDemo

 public class BuilderDemo{ public static void main(String args[]){ CDBuilder cdBuilder=new CDBuilder(); CDType cdType1=cdBuilder.buildSonyCD(); cdType1.showItems(); CDType cdType2=cdBuilder.buildSamsungCD(); cdType2.showItems(); } } 

Salida del ejemplo anterior

 CD name : Sony CD, Price : 20 CD name : Samsung CD, Price : 15 

Otro ejemplo del mundo real de Builder Pattern

UML para patrón constructor:

Estamos considerando un caso de negocio de Pizza Hut donde podremos conseguir diferentes variedades de pizza y bebida fría.

Pizza Puede ser una pizza vegetariana o una pizza no vegetariana de varios tipos (como pizza de queso, pizza de cebolla, pizza masala, etc.) y será de 4 tamaños, es decir, pequeña, mediana, grande y extragrande.

Bebida fría pueden ser de varios tipos (como Pepsi, Coke, Dew, Sprite, Fanta, Maaza, Limca, Thums-up etc.) y serán de 3 tamaños pequeño, mediano, grande.

Ejemplo del mundo real de patrón de construcción

Veamos el ejemplo del mundo real paso a paso de Builder Design Pattern.

doble a cadena java

Paso 1: Cree un elemento de interfaz que represente la pizza y la bebida fría.

 public interface Item { public String name(); public String size(); public float price(); }// End of the interface Item. 

Paso 2: Cree una clase abstracta Pizza que se implementará en la interfaz Item.

 public abstract class Pizza implements Item{ @Override public abstract float price(); } 

Paso 3: Cree una clase abstracta ColdDrink que se implementará en la interfaz Item.

 public abstract class ColdDrink implements Item{ @Override public abstract float price(); } 

Etapa 4: Cree una clase abstracta VegPizza que se extenderá a la clase abstracta Pizza.

 public abstract class VegPizza extends Pizza{ @Override public abstract float price(); @Override public abstract String name(); @Override public abstract String size(); }// End of the abstract class VegPizza. 

Paso 5: Cree una clase abstracta NonVegPizza que se extenderá a la clase abstracta Pizza.

 public abstract class NonVegPizza extends Pizza{ @Override public abstract float price(); @Override public abstract String name(); @Override public abstract String size(); }// End of the abstract class NonVegPizza. 

Paso 6: Ahora, cree subclases concretas SmallCheezePizza, MediumCheezePizza, LargeCheezePizza, ExtraLargeCheezePizza que se extenderán a la clase abstracta VegPizza.

 public class SmallCheezePizza extends VegPizza{ @Override public float price() { return 170.0f; } @Override public String name() { return 'Cheeze Pizza'; } @Override public String size() { return 'Small size'; } }// End of the SmallCheezePizza class. 

 public class MediumCheezePizza extends VegPizza{ @Override public float price() { return 220.f; } @Override public String name() { return &apos;Cheeze Pizza&apos;; } @Override public String size() { return &apos;Medium Size&apos;; } }// End of the MediumCheezePizza class. File: LargeCheezePizza.java <pre> public class LargeCheezePizza extends VegPizza{ @Override public float price() { return 260.0f; } @Override public String name() { return &apos;Cheeze Pizza&apos;; } @Override public String size() { return &apos;Large Size&apos;; } }// End of the LargeCheezePizza class. </pre> File: ExtraLargeCheezePizza.java <pre> public class ExtraLargeCheezePizza extends VegPizza{ @Override public float price() { return 300.f; } @Override public String name() { return &apos;Cheeze Pizza&apos;; } @Override public String size() { return &apos;Extra-Large Size&apos;; } }// End of the ExtraLargeCheezePizza class. </pre> <p>Step 7: <b>Now, similarly create concrete sub-classes SmallOnionPizza, MediumOnionPizza, LargeOnionPizza, ExtraLargeOnionPizza that will extend to the abstract class VegPizza.</b> </p> File: SmallOnionPizza.java <pre> public class SmallOnionPizza extends VegPizza { @Override public float price() { return 120.0f; } @Override public String name() { return &apos;Onion Pizza&apos;; } @Override public String size() { return &apos;Small Size&apos;; } }// End of the SmallOnionPizza class. </pre> File: MediumOnionPizza.java <pre> public class MediumOnionPizza extends VegPizza { @Override public float price() { return 150.0f; } @Override public String name() { return &apos;Onion Pizza&apos;; } @Override public String size() { return &apos;Medium Size&apos;; } }// End of the MediumOnionPizza class. </pre> File: LargeOnionPizza.java <pre> public class LargeOnionPizza extends VegPizza{ @Override public float price() { return 180.0f; } @Override public String name() { return &apos;Onion Pizza&apos;; } @Override public String size() { return &apos;Large size&apos;; } }// End of the LargeOnionPizza class. </pre> File: ExtraLargeOnionPizza.java <pre> public class ExtraLargeOnionPizza extends VegPizza { @Override public float price() { return 200.0f; } @Override public String name() { return &apos;Onion Pizza&apos;; } @Override public String size() { return &apos;Extra-Large Size&apos;; } }// End of the ExtraLargeOnionPizza class </pre> <p>Step 8: <b>Now, similarly create concrete sub-classes SmallMasalaPizza, MediumMasalaPizza, LargeMasalaPizza, ExtraLargeMasalaPizza that will extend to the abstract class VegPizza.</b> </p> File: SmallMasalaPizza.java <pre> public class SmallMasalaPizza extends VegPizza{ @Override public float price() { return 100.0f; } @Override public String name() { return &apos;Masala Pizza&apos;; } @Override public String size() { return &apos;Samll Size&apos;; } }// End of the SmallMasalaPizza class </pre> File: MediumMasalaPizza.java <pre> public class MediumMasalaPizza extends VegPizza { @Override public float price() { return 120.0f; } @Override public String name() { return &apos;Masala Pizza&apos;; } @Override public String size() { return &apos;Medium Size&apos;; } </pre> File: LargeMasalaPizza.java <pre> public class LargeMasalaPizza extends VegPizza{ @Override public float price() { return 150.0f; } @Override public String name() { return &apos;Masala Pizza&apos;; } @Override public String size() { return &apos;Large Size&apos;; } } //End of the LargeMasalaPizza class </pre> File: ExtraLargeMasalaPizza.java <pre> public class ExtraLargeMasalaPizza extends VegPizza { @Override public float price() { return 180.0f; } @Override public String name() { return &apos;Masala Pizza&apos;; } @Override public String size() { return &apos;Extra-Large Size&apos;; } }// End of the ExtraLargeMasalaPizza class </pre> <p>Step 9: <b>Now, create concrete sub-classes SmallNonVegPizza, MediumNonVegPizza, LargeNonVegPizza, ExtraLargeNonVegPizza that will extend to the abstract class NonVegPizza.</b> </p> File: SmallNonVegPizza.java <pre> public class SmallNonVegPizza extends NonVegPizza { @Override public float price() { return 180.0f; } @Override public String name() { return &apos;Non-Veg Pizza&apos;; } @Override public String size() { return &apos;Samll Size&apos;; } }// End of the SmallNonVegPizza class </pre> File: MediumNonVegPizza.java <pre> public class MediumNonVegPizza extends NonVegPizza{ @Override public float price() { return 200.0f; } @Override public String name() { return &apos;Non-Veg Pizza&apos;; } @Override public String size() { return &apos;Medium Size&apos;; } </pre> File: LargeNonVegPizza.java <pre> public class LargeNonVegPizza extends NonVegPizza{ @Override public float price() { return 220.0f; } @Override public String name() { return &apos;Non-Veg Pizza&apos;; } @Override public String size() { return &apos;Large Size&apos;; } }// End of the LargeNonVegPizza class </pre> File: ExtraLargeNonVegPizza.java <pre> public class ExtraLargeNonVegPizza extends NonVegPizza { @Override public float price() { return 250.0f; } @Override public String name() { return &apos;Non-Veg Pizza&apos;; } @Override public String size() { return &apos;Extra-Large Size&apos;; } } // End of the ExtraLargeNonVegPizza class </pre> <p>Step 10: <b>Now, create two abstract classes Pepsi and Coke that will extend abstract class ColdDrink. </b> </p> File: Pepsi.java <pre> public abstract class Pepsi extends ColdDrink { @Override public abstract String name(); @Override public abstract String size(); @Override public abstract float price(); }// End of the Pepsi class </pre> File: Coke.java <pre> public abstract class Coke extends ColdDrink { @Override public abstract String name(); @Override public abstract String size(); @Override public abstract float price(); }// End of the Coke class <p>Step 11: <b>Now, create concrete sub-classes SmallPepsi, MediumPepsi, LargePepsi that will extend to the abstract class Pepsi.</b> </p> File: SmallPepsi.java <pre> public class SmallPepsi extends Pepsi{ @Override public String name() { return &apos;300 ml Pepsi&apos;; } @Override public float price() { return 25.0f; } @Override public String size() { return &apos;Small Size&apos;; } }// End of the SmallPepsi class </pre> File: MediumPepsi.java <pre> public class MediumPepsi extends Pepsi { @Override public String name() { return &apos;500 ml Pepsi&apos;; } @Override public String size() { return &apos;Medium Size&apos;; } @Override public float price() { return 35.0f; } }// End of the MediumPepsi class </pre> File: LargePepsi.java <pre> public class LargePepsi extends Pepsi{ @Override public String name() { return &apos;750 ml Pepsi&apos;; } @Override public String size() { return &apos;Large Size&apos;; } @Override public float price() { return 50.0f; } }// End of the LargePepsi class </pre> <p>Step 12: <b>Now, create concrete sub-classes SmallCoke, MediumCoke, LargeCoke that will extend to the abstract class Coke.</b> </p> File: SmallCoke.java <pre> public class SmallCoke extends Coke{ @Override public String name() { return &apos;300 ml Coke&apos;; } @Override public String size() { return &apos;Small Size&apos;; } @Override public float price() { return 25.0f; } }// End of the SmallCoke class </pre> File: MediumCoke.java <pre> public class MediumCoke extends Coke{ @Override public String name() { return &apos;500 ml Coke&apos;; } @Override public String size() { return &apos;Medium Size&apos;; } @Override public float price() { return 35.0f; } }// End of the MediumCoke class </pre> File: LargeCoke.java <pre> public class LargeCoke extends Coke { @Override public String name() { return &apos;750 ml Coke&apos;; } @Override public String size() { return &apos;Large Size&apos;; } @Override public float price() { return 50.0f; } }// End of the LargeCoke class <p>Step 13: <b>Create an OrderedItems class that are having Item objects defined above.</b> </p> File: OrderedItems.java <pre> import java.util.ArrayList; import java.util.List; public class OrderedItems { List items=new ArrayList(); public void addItems(Item item){ items.add(item); } public float getCost(){ float cost=0.0f; for (Item item : items) { cost+=item.price(); } return cost; } public void showItems(){ for (Item item : items) { System.out.println(&apos;Item is:&apos; +item.name()); System.out.println(&apos;Size is:&apos; +item.size()); System.out.println(&apos;Price is: &apos; +item.price()); } } }// End of the OrderedItems class </pre> <p>Step 14: <b>Create an OrderBuilder class that will be responsible to create the objects of OrderedItems class.</b> </p> File: OrdereBuilder.java <pre> import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class OrderBuilder { public OrderedItems preparePizza() throws IOException{ OrderedItems itemsOrder=new OrderedItems(); BufferedReader br =new BufferedReader(new InputStreamReader(System.in)); System.out.println(&apos; Enter the choice of Pizza &apos;); System.out.println(&apos;============================&apos;); System.out.println(&apos; 1. Veg-Pizza &apos;); System.out.println(&apos; 2. Non-Veg Pizza &apos;); System.out.println(&apos; 3. Exit &apos;); System.out.println(&apos;============================&apos;); int pizzaandcolddrinkchoice=Integer.parseInt(br.readLine()); switch(pizzaandcolddrinkchoice) { case 1:{ System.out.println(&apos;You ordered Veg Pizza&apos;); System.out.println(&apos;

&apos;); System.out.println(&apos; Enter the types of Veg-Pizza &apos;); System.out.println(&apos;------------------------------&apos;); System.out.println(&apos; 1.Cheeze Pizza &apos;); System.out.println(&apos; 2.Onion Pizza &apos;); System.out.println(&apos; 3.Masala Pizza &apos;); System.out.println(&apos; 4.Exit &apos;); System.out.println(&apos;------------------------------&apos;); int vegpizzachoice=Integer.parseInt(br.readLine()); switch(vegpizzachoice) { case 1: { System.out.println(&apos;You ordered Cheeze Pizza&apos;); System.out.println(&apos;Enter the cheeze pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Cheeze Pizza &apos;); System.out.println(&apos; 2. Medium Cheeze Pizza &apos;); System.out.println(&apos; 3. Large Cheeze Pizza &apos;); System.out.println(&apos; 4. Extra-Large Cheeze Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int cheezepizzasize=Integer.parseInt(br.readLine()); switch(cheezepizzasize) { case 1: itemsOrder.addItems(new SmallCheezePizza()); break; case 2: itemsOrder.addItems(new MediumCheezePizza()); break; case 3: itemsOrder.addItems(new LargeCheezePizza()); break; case 4: itemsOrder.addItems(new ExtraLargeCheezePizza()); break; case 2: { System.out.println(&apos;You ordered Onion Pizza&apos;); System.out.println(&apos;Enter the Onion pizza size&apos;); System.out.println(&apos;----------------------------------&apos;); System.out.println(&apos; 1. Small Onion Pizza &apos;); System.out.println(&apos; 2. Medium Onion Pizza &apos;); System.out.println(&apos; 3. Large Onion Pizza &apos;); System.out.println(&apos; 4. Extra-Large Onion Pizza &apos;); System.out.println(&apos;----------------------------------&apos;); int onionpizzasize=Integer.parseInt(br.readLine()); switch(onionpizzasize) { case 1: itemsOrder.addItems(new SmallOnionPizza()); break; case 2: itemsOrder.addItems(new MediumOnionPizza()); break; case 3: itemsOrder.addItems(new LargeOnionPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeOnionPizza()); break; } } break; case 3: { System.out.println(&apos;You ordered Masala Pizza&apos;); System.out.println(&apos;Enter the Masala pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Masala Pizza &apos;); System.out.println(&apos; 2. Medium Masala Pizza &apos;); System.out.println(&apos; 3. Large Masala Pizza &apos;); System.out.println(&apos; 4. Extra-Large Masala Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int masalapizzasize=Integer.parseInt(br.readLine()); switch(masalapizzasize) { case 1: itemsOrder.addItems(new SmallMasalaPizza()); break; case 2: itemsOrder.addItems(new MediumMasalaPizza()); break; case 3: itemsOrder.addItems(new LargeMasalaPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeMasalaPizza()); break; } } break; } } break;// Veg- pizza choice completed. case 2: { System.out.println(&apos;You ordered Non-Veg Pizza&apos;); System.out.println(&apos;

&apos;); System.out.println(&apos;Enter the Non-Veg pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Non-Veg Pizza &apos;); System.out.println(&apos; 2. Medium Non-Veg Pizza &apos;); System.out.println(&apos; 3. Large Non-Veg Pizza &apos;); System.out.println(&apos; 4. Extra-Large Non-Veg Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int nonvegpizzasize=Integer.parseInt(br.readLine()); switch(nonvegpizzasize) { case 1: itemsOrder.addItems(new SmallNonVegPizza()); break; case 2: itemsOrder.addItems(new MediumNonVegPizza()); break; case 3: itemsOrder.addItems(new LargeNonVegPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeNonVegPizza()); break; } } break; default: { break; } }//end of main Switch //continued?.. System.out.println(&apos; Enter the choice of ColdDrink &apos;); System.out.println(&apos;============================&apos;); System.out.println(&apos; 1. Pepsi &apos;); System.out.println(&apos; 2. Coke &apos;); System.out.println(&apos; 3. Exit &apos;); System.out.println(&apos;============================&apos;); int coldDrink=Integer.parseInt(br.readLine()); switch (coldDrink) { case 1: { System.out.println(&apos;You ordered Pepsi &apos;); System.out.println(&apos;Enter the Pepsi Size &apos;); System.out.println(&apos;------------------------&apos;); System.out.println(&apos; 1. Small Pepsi &apos;); System.out.println(&apos; 2. Medium Pepsi &apos;); System.out.println(&apos; 3. Large Pepsi &apos;); System.out.println(&apos;------------------------&apos;); int pepsisize=Integer.parseInt(br.readLine()); switch(pepsisize) { case 1: itemsOrder.addItems(new SmallPepsi()); break; case 2: itemsOrder.addItems(new MediumPepsi()); break; case 3: itemsOrder.addItems(new LargePepsi()); break; } } break; case 2: { System.out.println(&apos;You ordered Coke&apos;); System.out.println(&apos;Enter the Coke Size&apos;); System.out.println(&apos;------------------------&apos;); System.out.println(&apos; 1. Small Coke &apos;); System.out.println(&apos; 2. Medium Coke &apos;); System.out.println(&apos; 3. Large Coke &apos;); System.out.println(&apos; 4. Extra-Large Coke &apos;); System.out.println(&apos;------------------------&apos;); int cokesize=Integer.parseInt(br.readLine()); switch(cokesize) { case 1: itemsOrder.addItems(new SmallCoke()); break; case 2: itemsOrder.addItems(new MediumCoke()); break; case 3: itemsOrder.addItems(new LargeCoke()); break; } } break; default: { break; } }//End of the Cold-Drink switch return itemsOrder; } //End of the preparePizza() method </pre> <p>Step 15: <b>Create a BuilderDemo class that will use the OrderBuilder class.</b> </p> File: Prototype.java <pre> import java.io.IOException; public class BuilderDemo { public static void main(String[] args) throws IOException { // TODO code application logic here OrderBuilder builder=new OrderBuilder(); OrderedItems orderedItems=builder.preparePizza(); orderedItems.showItems(); System.out.println(&apos;
&apos;); System.out.println(&apos;Total Cost : &apos;+ orderedItems.getCost()); } }// End of the BuilderDemo class </pre> <hr> download this Builder Pattern Example <h4>Output</h4>  </pre></pre>

 public class ExtraLargeCheezePizza extends VegPizza{ @Override public float price() { return 300.f; } @Override public String name() { return 'Cheeze Pizza'; } @Override public String size() { return 'Extra-Large Size'; } }// End of the ExtraLargeCheezePizza class. 

Paso 7: Ahora, cree de manera similar subclases concretas SmallOnionPizza, MediumOnionPizza, LargeOnionPizza, ExtraLargeOnionPizza que se extenderán a la clase abstracta VegPizza.

 public class SmallOnionPizza extends VegPizza { @Override public float price() { return 120.0f; } @Override public String name() { return 'Onion Pizza'; } @Override public String size() { return 'Small Size'; } }// End of the SmallOnionPizza class. 

 public class MediumOnionPizza extends VegPizza { @Override public float price() { return 150.0f; } @Override public String name() { return 'Onion Pizza'; } @Override public String size() { return 'Medium Size'; } }// End of the MediumOnionPizza class. 

 public class LargeOnionPizza extends VegPizza{ @Override public float price() { return 180.0f; } @Override public String name() { return 'Onion Pizza'; } @Override public String size() { return 'Large size'; } }// End of the LargeOnionPizza class. 

 public class ExtraLargeOnionPizza extends VegPizza { @Override public float price() { return 200.0f; } @Override public String name() { return 'Onion Pizza'; } @Override public String size() { return 'Extra-Large Size'; } }// End of the ExtraLargeOnionPizza class 

Paso 8: Ahora, cree de manera similar subclases concretas SmallMasalaPizza, MediumMasalaPizza, LargeMasalaPizza, ExtraLargeMasalaPizza que se extenderán a la clase abstracta VegPizza.

 public class SmallMasalaPizza extends VegPizza{ @Override public float price() { return 100.0f; } @Override public String name() { return 'Masala Pizza'; } @Override public String size() { return 'Samll Size'; } }// End of the SmallMasalaPizza class 

 public class MediumMasalaPizza extends VegPizza { @Override public float price() { return 120.0f; } @Override public String name() { return 'Masala Pizza'; } @Override public String size() { return 'Medium Size'; } 

 public class LargeMasalaPizza extends VegPizza{ @Override public float price() { return 150.0f; } @Override public String name() { return 'Masala Pizza'; } @Override public String size() { return 'Large Size'; } } //End of the LargeMasalaPizza class 

 public class ExtraLargeMasalaPizza extends VegPizza { @Override public float price() { return 180.0f; } @Override public String name() { return 'Masala Pizza'; } @Override public String size() { return 'Extra-Large Size'; } }// End of the ExtraLargeMasalaPizza class 

Paso 9: Ahora, cree subclases concretas SmallNonVegPizza, MediumNonVegPizza, LargeNonVegPizza, ExtraLargeNonVegPizza que se extenderán a la clase abstracta NonVegPizza.

 public class SmallNonVegPizza extends NonVegPizza { @Override public float price() { return 180.0f; } @Override public String name() { return 'Non-Veg Pizza'; } @Override public String size() { return 'Samll Size'; } }// End of the SmallNonVegPizza class 

 public class MediumNonVegPizza extends NonVegPizza{ @Override public float price() { return 200.0f; } @Override public String name() { return 'Non-Veg Pizza'; } @Override public String size() { return 'Medium Size'; } 

 public class LargeNonVegPizza extends NonVegPizza{ @Override public float price() { return 220.0f; } @Override public String name() { return 'Non-Veg Pizza'; } @Override public String size() { return 'Large Size'; } }// End of the LargeNonVegPizza class 

 public class ExtraLargeNonVegPizza extends NonVegPizza { @Override public float price() { return 250.0f; } @Override public String name() { return 'Non-Veg Pizza'; } @Override public String size() { return 'Extra-Large Size'; } } // End of the ExtraLargeNonVegPizza class 

Paso 10: Ahora, cree dos clases abstractas, Pepsi y Coca-Cola, que ampliarán la clase abstracta ColdDrink.

 public abstract class Pepsi extends ColdDrink { @Override public abstract String name(); @Override public abstract String size(); @Override public abstract float price(); }// End of the Pepsi class 

 public abstract class Coke extends ColdDrink { @Override public abstract String name(); @Override public abstract String size(); @Override public abstract float price(); }// End of the Coke class <p>Step 11: <b>Now, create concrete sub-classes SmallPepsi, MediumPepsi, LargePepsi that will extend to the abstract class Pepsi.</b> </p> File: SmallPepsi.java <pre> public class SmallPepsi extends Pepsi{ @Override public String name() { return &apos;300 ml Pepsi&apos;; } @Override public float price() { return 25.0f; } @Override public String size() { return &apos;Small Size&apos;; } }// End of the SmallPepsi class </pre> File: MediumPepsi.java <pre> public class MediumPepsi extends Pepsi { @Override public String name() { return &apos;500 ml Pepsi&apos;; } @Override public String size() { return &apos;Medium Size&apos;; } @Override public float price() { return 35.0f; } }// End of the MediumPepsi class </pre> File: LargePepsi.java <pre> public class LargePepsi extends Pepsi{ @Override public String name() { return &apos;750 ml Pepsi&apos;; } @Override public String size() { return &apos;Large Size&apos;; } @Override public float price() { return 50.0f; } }// End of the LargePepsi class </pre> <p>Step 12: <b>Now, create concrete sub-classes SmallCoke, MediumCoke, LargeCoke that will extend to the abstract class Coke.</b> </p> File: SmallCoke.java <pre> public class SmallCoke extends Coke{ @Override public String name() { return &apos;300 ml Coke&apos;; } @Override public String size() { return &apos;Small Size&apos;; } @Override public float price() { return 25.0f; } }// End of the SmallCoke class </pre> File: MediumCoke.java <pre> public class MediumCoke extends Coke{ @Override public String name() { return &apos;500 ml Coke&apos;; } @Override public String size() { return &apos;Medium Size&apos;; } @Override public float price() { return 35.0f; } }// End of the MediumCoke class </pre> File: LargeCoke.java <pre> public class LargeCoke extends Coke { @Override public String name() { return &apos;750 ml Coke&apos;; } @Override public String size() { return &apos;Large Size&apos;; } @Override public float price() { return 50.0f; } }// End of the LargeCoke class <p>Step 13: <b>Create an OrderedItems class that are having Item objects defined above.</b> </p> File: OrderedItems.java <pre> import java.util.ArrayList; import java.util.List; public class OrderedItems { List items=new ArrayList(); public void addItems(Item item){ items.add(item); } public float getCost(){ float cost=0.0f; for (Item item : items) { cost+=item.price(); } return cost; } public void showItems(){ for (Item item : items) { System.out.println(&apos;Item is:&apos; +item.name()); System.out.println(&apos;Size is:&apos; +item.size()); System.out.println(&apos;Price is: &apos; +item.price()); } } }// End of the OrderedItems class </pre> <p>Step 14: <b>Create an OrderBuilder class that will be responsible to create the objects of OrderedItems class.</b> </p> File: OrdereBuilder.java <pre> import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class OrderBuilder { public OrderedItems preparePizza() throws IOException{ OrderedItems itemsOrder=new OrderedItems(); BufferedReader br =new BufferedReader(new InputStreamReader(System.in)); System.out.println(&apos; Enter the choice of Pizza &apos;); System.out.println(&apos;============================&apos;); System.out.println(&apos; 1. Veg-Pizza &apos;); System.out.println(&apos; 2. Non-Veg Pizza &apos;); System.out.println(&apos; 3. Exit &apos;); System.out.println(&apos;============================&apos;); int pizzaandcolddrinkchoice=Integer.parseInt(br.readLine()); switch(pizzaandcolddrinkchoice) { case 1:{ System.out.println(&apos;You ordered Veg Pizza&apos;); System.out.println(&apos;

&apos;); System.out.println(&apos; Enter the types of Veg-Pizza &apos;); System.out.println(&apos;------------------------------&apos;); System.out.println(&apos; 1.Cheeze Pizza &apos;); System.out.println(&apos; 2.Onion Pizza &apos;); System.out.println(&apos; 3.Masala Pizza &apos;); System.out.println(&apos; 4.Exit &apos;); System.out.println(&apos;------------------------------&apos;); int vegpizzachoice=Integer.parseInt(br.readLine()); switch(vegpizzachoice) { case 1: { System.out.println(&apos;You ordered Cheeze Pizza&apos;); System.out.println(&apos;Enter the cheeze pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Cheeze Pizza &apos;); System.out.println(&apos; 2. Medium Cheeze Pizza &apos;); System.out.println(&apos; 3. Large Cheeze Pizza &apos;); System.out.println(&apos; 4. Extra-Large Cheeze Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int cheezepizzasize=Integer.parseInt(br.readLine()); switch(cheezepizzasize) { case 1: itemsOrder.addItems(new SmallCheezePizza()); break; case 2: itemsOrder.addItems(new MediumCheezePizza()); break; case 3: itemsOrder.addItems(new LargeCheezePizza()); break; case 4: itemsOrder.addItems(new ExtraLargeCheezePizza()); break; case 2: { System.out.println(&apos;You ordered Onion Pizza&apos;); System.out.println(&apos;Enter the Onion pizza size&apos;); System.out.println(&apos;----------------------------------&apos;); System.out.println(&apos; 1. Small Onion Pizza &apos;); System.out.println(&apos; 2. Medium Onion Pizza &apos;); System.out.println(&apos; 3. Large Onion Pizza &apos;); System.out.println(&apos; 4. Extra-Large Onion Pizza &apos;); System.out.println(&apos;----------------------------------&apos;); int onionpizzasize=Integer.parseInt(br.readLine()); switch(onionpizzasize) { case 1: itemsOrder.addItems(new SmallOnionPizza()); break; case 2: itemsOrder.addItems(new MediumOnionPizza()); break; case 3: itemsOrder.addItems(new LargeOnionPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeOnionPizza()); break; } } break; case 3: { System.out.println(&apos;You ordered Masala Pizza&apos;); System.out.println(&apos;Enter the Masala pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Masala Pizza &apos;); System.out.println(&apos; 2. Medium Masala Pizza &apos;); System.out.println(&apos; 3. Large Masala Pizza &apos;); System.out.println(&apos; 4. Extra-Large Masala Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int masalapizzasize=Integer.parseInt(br.readLine()); switch(masalapizzasize) { case 1: itemsOrder.addItems(new SmallMasalaPizza()); break; case 2: itemsOrder.addItems(new MediumMasalaPizza()); break; case 3: itemsOrder.addItems(new LargeMasalaPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeMasalaPizza()); break; } } break; } } break;// Veg- pizza choice completed. case 2: { System.out.println(&apos;You ordered Non-Veg Pizza&apos;); System.out.println(&apos;

&apos;); System.out.println(&apos;Enter the Non-Veg pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Non-Veg Pizza &apos;); System.out.println(&apos; 2. Medium Non-Veg Pizza &apos;); System.out.println(&apos; 3. Large Non-Veg Pizza &apos;); System.out.println(&apos; 4. Extra-Large Non-Veg Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int nonvegpizzasize=Integer.parseInt(br.readLine()); switch(nonvegpizzasize) { case 1: itemsOrder.addItems(new SmallNonVegPizza()); break; case 2: itemsOrder.addItems(new MediumNonVegPizza()); break; case 3: itemsOrder.addItems(new LargeNonVegPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeNonVegPizza()); break; } } break; default: { break; } }//end of main Switch //continued?.. System.out.println(&apos; Enter the choice of ColdDrink &apos;); System.out.println(&apos;============================&apos;); System.out.println(&apos; 1. Pepsi &apos;); System.out.println(&apos; 2. Coke &apos;); System.out.println(&apos; 3. Exit &apos;); System.out.println(&apos;============================&apos;); int coldDrink=Integer.parseInt(br.readLine()); switch (coldDrink) { case 1: { System.out.println(&apos;You ordered Pepsi &apos;); System.out.println(&apos;Enter the Pepsi Size &apos;); System.out.println(&apos;------------------------&apos;); System.out.println(&apos; 1. Small Pepsi &apos;); System.out.println(&apos; 2. Medium Pepsi &apos;); System.out.println(&apos; 3. Large Pepsi &apos;); System.out.println(&apos;------------------------&apos;); int pepsisize=Integer.parseInt(br.readLine()); switch(pepsisize) { case 1: itemsOrder.addItems(new SmallPepsi()); break; case 2: itemsOrder.addItems(new MediumPepsi()); break; case 3: itemsOrder.addItems(new LargePepsi()); break; } } break; case 2: { System.out.println(&apos;You ordered Coke&apos;); System.out.println(&apos;Enter the Coke Size&apos;); System.out.println(&apos;------------------------&apos;); System.out.println(&apos; 1. Small Coke &apos;); System.out.println(&apos; 2. Medium Coke &apos;); System.out.println(&apos; 3. Large Coke &apos;); System.out.println(&apos; 4. Extra-Large Coke &apos;); System.out.println(&apos;------------------------&apos;); int cokesize=Integer.parseInt(br.readLine()); switch(cokesize) { case 1: itemsOrder.addItems(new SmallCoke()); break; case 2: itemsOrder.addItems(new MediumCoke()); break; case 3: itemsOrder.addItems(new LargeCoke()); break; } } break; default: { break; } }//End of the Cold-Drink switch return itemsOrder; } //End of the preparePizza() method </pre> <p>Step 15: <b>Create a BuilderDemo class that will use the OrderBuilder class.</b> </p> File: Prototype.java <pre> import java.io.IOException; public class BuilderDemo { public static void main(String[] args) throws IOException { // TODO code application logic here OrderBuilder builder=new OrderBuilder(); OrderedItems orderedItems=builder.preparePizza(); orderedItems.showItems(); System.out.println(&apos;
&apos;); System.out.println(&apos;Total Cost : &apos;+ orderedItems.getCost()); } }// End of the BuilderDemo class </pre> <hr> download this Builder Pattern Example <h4>Output</h4>  </pre>

 public class MediumPepsi extends Pepsi { @Override public String name() { return '500 ml Pepsi'; } @Override public String size() { return 'Medium Size'; } @Override public float price() { return 35.0f; } }// End of the MediumPepsi class 

 public class LargePepsi extends Pepsi{ @Override public String name() { return '750 ml Pepsi'; } @Override public String size() { return 'Large Size'; } @Override public float price() { return 50.0f; } }// End of the LargePepsi class 

Paso 12: Ahora, cree subclases concretas SmallCoke, MediumCoke, LargeCoke que se extenderán a la clase abstracta Coke.

 public class SmallCoke extends Coke{ @Override public String name() { return '300 ml Coke'; } @Override public String size() { return 'Small Size'; } @Override public float price() { return 25.0f; } }// End of the SmallCoke class 

 public class MediumCoke extends Coke{ @Override public String name() { return '500 ml Coke'; } @Override public String size() { return 'Medium Size'; } @Override public float price() { return 35.0f; } }// End of the MediumCoke class 

 public class LargeCoke extends Coke { @Override public String name() { return &apos;750 ml Coke&apos;; } @Override public String size() { return &apos;Large Size&apos;; } @Override public float price() { return 50.0f; } }// End of the LargeCoke class <p>Step 13: <b>Create an OrderedItems class that are having Item objects defined above.</b> </p> File: OrderedItems.java <pre> import java.util.ArrayList; import java.util.List; public class OrderedItems { List items=new ArrayList(); public void addItems(Item item){ items.add(item); } public float getCost(){ float cost=0.0f; for (Item item : items) { cost+=item.price(); } return cost; } public void showItems(){ for (Item item : items) { System.out.println(&apos;Item is:&apos; +item.name()); System.out.println(&apos;Size is:&apos; +item.size()); System.out.println(&apos;Price is: &apos; +item.price()); } } }// End of the OrderedItems class </pre> <p>Step 14: <b>Create an OrderBuilder class that will be responsible to create the objects of OrderedItems class.</b> </p> File: OrdereBuilder.java <pre> import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class OrderBuilder { public OrderedItems preparePizza() throws IOException{ OrderedItems itemsOrder=new OrderedItems(); BufferedReader br =new BufferedReader(new InputStreamReader(System.in)); System.out.println(&apos; Enter the choice of Pizza &apos;); System.out.println(&apos;============================&apos;); System.out.println(&apos; 1. Veg-Pizza &apos;); System.out.println(&apos; 2. Non-Veg Pizza &apos;); System.out.println(&apos; 3. Exit &apos;); System.out.println(&apos;============================&apos;); int pizzaandcolddrinkchoice=Integer.parseInt(br.readLine()); switch(pizzaandcolddrinkchoice) { case 1:{ System.out.println(&apos;You ordered Veg Pizza&apos;); System.out.println(&apos;

&apos;); System.out.println(&apos; Enter the types of Veg-Pizza &apos;); System.out.println(&apos;------------------------------&apos;); System.out.println(&apos; 1.Cheeze Pizza &apos;); System.out.println(&apos; 2.Onion Pizza &apos;); System.out.println(&apos; 3.Masala Pizza &apos;); System.out.println(&apos; 4.Exit &apos;); System.out.println(&apos;------------------------------&apos;); int vegpizzachoice=Integer.parseInt(br.readLine()); switch(vegpizzachoice) { case 1: { System.out.println(&apos;You ordered Cheeze Pizza&apos;); System.out.println(&apos;Enter the cheeze pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Cheeze Pizza &apos;); System.out.println(&apos; 2. Medium Cheeze Pizza &apos;); System.out.println(&apos; 3. Large Cheeze Pizza &apos;); System.out.println(&apos; 4. Extra-Large Cheeze Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int cheezepizzasize=Integer.parseInt(br.readLine()); switch(cheezepizzasize) { case 1: itemsOrder.addItems(new SmallCheezePizza()); break; case 2: itemsOrder.addItems(new MediumCheezePizza()); break; case 3: itemsOrder.addItems(new LargeCheezePizza()); break; case 4: itemsOrder.addItems(new ExtraLargeCheezePizza()); break; case 2: { System.out.println(&apos;You ordered Onion Pizza&apos;); System.out.println(&apos;Enter the Onion pizza size&apos;); System.out.println(&apos;----------------------------------&apos;); System.out.println(&apos; 1. Small Onion Pizza &apos;); System.out.println(&apos; 2. Medium Onion Pizza &apos;); System.out.println(&apos; 3. Large Onion Pizza &apos;); System.out.println(&apos; 4. Extra-Large Onion Pizza &apos;); System.out.println(&apos;----------------------------------&apos;); int onionpizzasize=Integer.parseInt(br.readLine()); switch(onionpizzasize) { case 1: itemsOrder.addItems(new SmallOnionPizza()); break; case 2: itemsOrder.addItems(new MediumOnionPizza()); break; case 3: itemsOrder.addItems(new LargeOnionPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeOnionPizza()); break; } } break; case 3: { System.out.println(&apos;You ordered Masala Pizza&apos;); System.out.println(&apos;Enter the Masala pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Masala Pizza &apos;); System.out.println(&apos; 2. Medium Masala Pizza &apos;); System.out.println(&apos; 3. Large Masala Pizza &apos;); System.out.println(&apos; 4. Extra-Large Masala Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int masalapizzasize=Integer.parseInt(br.readLine()); switch(masalapizzasize) { case 1: itemsOrder.addItems(new SmallMasalaPizza()); break; case 2: itemsOrder.addItems(new MediumMasalaPizza()); break; case 3: itemsOrder.addItems(new LargeMasalaPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeMasalaPizza()); break; } } break; } } break;// Veg- pizza choice completed. case 2: { System.out.println(&apos;You ordered Non-Veg Pizza&apos;); System.out.println(&apos;

&apos;); System.out.println(&apos;Enter the Non-Veg pizza size&apos;); System.out.println(&apos;------------------------------------&apos;); System.out.println(&apos; 1. Small Non-Veg Pizza &apos;); System.out.println(&apos; 2. Medium Non-Veg Pizza &apos;); System.out.println(&apos; 3. Large Non-Veg Pizza &apos;); System.out.println(&apos; 4. Extra-Large Non-Veg Pizza &apos;); System.out.println(&apos;------------------------------------&apos;); int nonvegpizzasize=Integer.parseInt(br.readLine()); switch(nonvegpizzasize) { case 1: itemsOrder.addItems(new SmallNonVegPizza()); break; case 2: itemsOrder.addItems(new MediumNonVegPizza()); break; case 3: itemsOrder.addItems(new LargeNonVegPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeNonVegPizza()); break; } } break; default: { break; } }//end of main Switch //continued?.. System.out.println(&apos; Enter the choice of ColdDrink &apos;); System.out.println(&apos;============================&apos;); System.out.println(&apos; 1. Pepsi &apos;); System.out.println(&apos; 2. Coke &apos;); System.out.println(&apos; 3. Exit &apos;); System.out.println(&apos;============================&apos;); int coldDrink=Integer.parseInt(br.readLine()); switch (coldDrink) { case 1: { System.out.println(&apos;You ordered Pepsi &apos;); System.out.println(&apos;Enter the Pepsi Size &apos;); System.out.println(&apos;------------------------&apos;); System.out.println(&apos; 1. Small Pepsi &apos;); System.out.println(&apos; 2. Medium Pepsi &apos;); System.out.println(&apos; 3. Large Pepsi &apos;); System.out.println(&apos;------------------------&apos;); int pepsisize=Integer.parseInt(br.readLine()); switch(pepsisize) { case 1: itemsOrder.addItems(new SmallPepsi()); break; case 2: itemsOrder.addItems(new MediumPepsi()); break; case 3: itemsOrder.addItems(new LargePepsi()); break; } } break; case 2: { System.out.println(&apos;You ordered Coke&apos;); System.out.println(&apos;Enter the Coke Size&apos;); System.out.println(&apos;------------------------&apos;); System.out.println(&apos; 1. Small Coke &apos;); System.out.println(&apos; 2. Medium Coke &apos;); System.out.println(&apos; 3. Large Coke &apos;); System.out.println(&apos; 4. Extra-Large Coke &apos;); System.out.println(&apos;------------------------&apos;); int cokesize=Integer.parseInt(br.readLine()); switch(cokesize) { case 1: itemsOrder.addItems(new SmallCoke()); break; case 2: itemsOrder.addItems(new MediumCoke()); break; case 3: itemsOrder.addItems(new LargeCoke()); break; } } break; default: { break; } }//End of the Cold-Drink switch return itemsOrder; } //End of the preparePizza() method </pre> <p>Step 15: <b>Create a BuilderDemo class that will use the OrderBuilder class.</b> </p> File: Prototype.java <pre> import java.io.IOException; public class BuilderDemo { public static void main(String[] args) throws IOException { // TODO code application logic here OrderBuilder builder=new OrderBuilder(); OrderedItems orderedItems=builder.preparePizza(); orderedItems.showItems(); System.out.println(&apos;
&apos;); System.out.println(&apos;Total Cost : &apos;+ orderedItems.getCost()); } }// End of the BuilderDemo class </pre> <hr> download this Builder Pattern Example <h4>Output</h4>  

Paso 14: Cree una clase OrderBuilder que será responsable de crear los objetos de la clase OrderedItems.

 import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class OrderBuilder { public OrderedItems preparePizza() throws IOException{ OrderedItems itemsOrder=new OrderedItems(); BufferedReader br =new BufferedReader(new InputStreamReader(System.in)); System.out.println(' Enter the choice of Pizza '); System.out.println('============================'); System.out.println(' 1. Veg-Pizza '); System.out.println(' 2. Non-Veg Pizza '); System.out.println(' 3. Exit '); System.out.println('============================'); int pizzaandcolddrinkchoice=Integer.parseInt(br.readLine()); switch(pizzaandcolddrinkchoice) { case 1:{ System.out.println('You ordered Veg Pizza'); System.out.println('

'); System.out.println(' Enter the types of Veg-Pizza '); System.out.println('------------------------------'); System.out.println(' 1.Cheeze Pizza '); System.out.println(' 2.Onion Pizza '); System.out.println(' 3.Masala Pizza '); System.out.println(' 4.Exit '); System.out.println('------------------------------'); int vegpizzachoice=Integer.parseInt(br.readLine()); switch(vegpizzachoice) { case 1: { System.out.println('You ordered Cheeze Pizza'); System.out.println('Enter the cheeze pizza size'); System.out.println('------------------------------------'); System.out.println(' 1. Small Cheeze Pizza '); System.out.println(' 2. Medium Cheeze Pizza '); System.out.println(' 3. Large Cheeze Pizza '); System.out.println(' 4. Extra-Large Cheeze Pizza '); System.out.println('------------------------------------'); int cheezepizzasize=Integer.parseInt(br.readLine()); switch(cheezepizzasize) { case 1: itemsOrder.addItems(new SmallCheezePizza()); break; case 2: itemsOrder.addItems(new MediumCheezePizza()); break; case 3: itemsOrder.addItems(new LargeCheezePizza()); break; case 4: itemsOrder.addItems(new ExtraLargeCheezePizza()); break; case 2: { System.out.println('You ordered Onion Pizza'); System.out.println('Enter the Onion pizza size'); System.out.println('----------------------------------'); System.out.println(' 1. Small Onion Pizza '); System.out.println(' 2. Medium Onion Pizza '); System.out.println(' 3. Large Onion Pizza '); System.out.println(' 4. Extra-Large Onion Pizza '); System.out.println('----------------------------------'); int onionpizzasize=Integer.parseInt(br.readLine()); switch(onionpizzasize) { case 1: itemsOrder.addItems(new SmallOnionPizza()); break; case 2: itemsOrder.addItems(new MediumOnionPizza()); break; case 3: itemsOrder.addItems(new LargeOnionPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeOnionPizza()); break; } } break; case 3: { System.out.println('You ordered Masala Pizza'); System.out.println('Enter the Masala pizza size'); System.out.println('------------------------------------'); System.out.println(' 1. Small Masala Pizza '); System.out.println(' 2. Medium Masala Pizza '); System.out.println(' 3. Large Masala Pizza '); System.out.println(' 4. Extra-Large Masala Pizza '); System.out.println('------------------------------------'); int masalapizzasize=Integer.parseInt(br.readLine()); switch(masalapizzasize) { case 1: itemsOrder.addItems(new SmallMasalaPizza()); break; case 2: itemsOrder.addItems(new MediumMasalaPizza()); break; case 3: itemsOrder.addItems(new LargeMasalaPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeMasalaPizza()); break; } } break; } } break;// Veg- pizza choice completed. case 2: { System.out.println('You ordered Non-Veg Pizza'); System.out.println('

'); System.out.println('Enter the Non-Veg pizza size'); System.out.println('------------------------------------'); System.out.println(' 1. Small Non-Veg Pizza '); System.out.println(' 2. Medium Non-Veg Pizza '); System.out.println(' 3. Large Non-Veg Pizza '); System.out.println(' 4. Extra-Large Non-Veg Pizza '); System.out.println('------------------------------------'); int nonvegpizzasize=Integer.parseInt(br.readLine()); switch(nonvegpizzasize) { case 1: itemsOrder.addItems(new SmallNonVegPizza()); break; case 2: itemsOrder.addItems(new MediumNonVegPizza()); break; case 3: itemsOrder.addItems(new LargeNonVegPizza()); break; case 4: itemsOrder.addItems(new ExtraLargeNonVegPizza()); break; } } break; default: { break; } }//end of main Switch //continued?.. System.out.println(' Enter the choice of ColdDrink '); System.out.println('============================'); System.out.println(' 1. Pepsi '); System.out.println(' 2. Coke '); System.out.println(' 3. Exit '); System.out.println('============================'); int coldDrink=Integer.parseInt(br.readLine()); switch (coldDrink) { case 1: { System.out.println('You ordered Pepsi '); System.out.println('Enter the Pepsi Size '); System.out.println('------------------------'); System.out.println(' 1. Small Pepsi '); System.out.println(' 2. Medium Pepsi '); System.out.println(' 3. Large Pepsi '); System.out.println('------------------------'); int pepsisize=Integer.parseInt(br.readLine()); switch(pepsisize) { case 1: itemsOrder.addItems(new SmallPepsi()); break; case 2: itemsOrder.addItems(new MediumPepsi()); break; case 3: itemsOrder.addItems(new LargePepsi()); break; } } break; case 2: { System.out.println('You ordered Coke'); System.out.println('Enter the Coke Size'); System.out.println('------------------------'); System.out.println(' 1. Small Coke '); System.out.println(' 2. Medium Coke '); System.out.println(' 3. Large Coke '); System.out.println(' 4. Extra-Large Coke '); System.out.println('------------------------'); int cokesize=Integer.parseInt(br.readLine()); switch(cokesize) { case 1: itemsOrder.addItems(new SmallCoke()); break; case 2: itemsOrder.addItems(new MediumCoke()); break; case 3: itemsOrder.addItems(new LargeCoke()); break; } } break; default: { break; } }//End of the Cold-Drink switch return itemsOrder; } //End of the preparePizza() method 

Paso 15: Cree una clase BuilderDemo que utilizará la clase OrderBuilder.

 import java.io.IOException; public class BuilderDemo { public static void main(String[] args) throws IOException { // TODO code application logic here OrderBuilder builder=new OrderBuilder(); OrderedItems orderedItems=builder.preparePizza(); orderedItems.showItems(); System.out.println('
'); System.out.println('Total Cost : '+ orderedItems.getCost()); } }// End of the BuilderDemo class 

Producción