1. Builder-Entwurfsmuster
2. Vorteil von Builder DP
3. Verwendung von Builder DP
4. UML von Builder DP
5. Beispiel für Builder DP

Builder Pattern sagt das „Ein komplexes Objekt aus einfachen Objekten schrittweise konstruieren“

Es wird hauptsächlich verwendet, wenn ein Objekt nicht in einem einzigen Schritt erstellt werden kann, wie z. B. bei der Deserialisierung eines komplexen Objekts.

Vorteil des Builder-Entwurfsmusters

Die Hauptvorteile von Builder Pattern sind folgende:

• Es sorgt für eine klare Trennung zwischen der Konstruktion und der Darstellung eines Objekts.
• Es bietet eine bessere Kontrolle über den Bauprozess.
• Es unterstützt die Änderung der internen Darstellung von Objekten.

Beispiel für UML für Builder-Muster

Beispiel eines Builder-Entwurfsmusters

Um ein einfaches Beispiel für ein Builder-Entwurfsmuster zu erstellen, müssen Sie die folgenden sechs Schritte ausführen.

1. Erstellen Sie eine Verpackungsschnittstelle
2. Erstellen Sie zwei abstrakte Klassen „CD“ und „Unternehmen“.
3. Erstellen Sie zwei Implementierungsklassen von Unternehmen: Sony und Samsung
4. Erstellen Sie die CDType-Klasse
5. Erstellen Sie die CDBuilder-Klasse
6. Erstellen Sie die BuilderDemo-Klasse

1) Erstellen Sie eine Verpackungsschnittstelle

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

2) Erstellen Sie zwei abstrakte Klassen „CD“ und „Unternehmen“.

Erstellen Sie eine abstrakte Klassen-CD, die die Packing-Schnittstelle implementiert.

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

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

3) Erstellen Sie zwei Implementierungsklassen von Unternehmen: Sony und 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) Erstellen Sie die CDType-Klasse

 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) Erstellen Sie die CDBuilder-Klasse

 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) Erstellen Sie die BuilderDemo-Klasse

 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(); } } 

Ausgabe des obigen Beispiels

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

Ein weiteres Beispiel aus der Praxis für Builder Pattern

UML für Builder-Muster:

Wir erwägen einen Business Case von Pizza Hut wo wir verschiedene Pizzasorten und Kaltgetränke bekommen können.

Pizza Es kann entweder eine vegetarische Pizza oder eine nicht-vegetarische Pizza verschiedener Art sein (wie Käsepizza, Zwiebelpizza, Masala-Pizza usw.) und ist in 4 Größen erhältlich, d. h. klein, mittel, groß, extragroß.

Kaltes Getränk Es gibt verschiedene Arten (wie Pepsi, Coke, Dew, Sprite, Fanta, Maaza, Limca, Thums-up usw.) und es gibt sie in den drei Größen klein, mittel und groß.

Beispiel aus der Praxis eines Builder-Musters

Sehen wir uns Schritt für Schritt das reale Beispiel des Builder Design Pattern an.

Schritt 1: Erstellen Sie ein Schnittstellenelement, das Pizza und Kaltgetränke darstellt.

Java-Bool zum String

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

Schritt 2: Erstellen Sie eine abstrakte Klasse Pizza, die in die Schnittstelle Item implementiert wird.

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

Schritt 3: Erstellen Sie eine abstrakte Klasse ColdDrink, die in die Schnittstelle Item implementiert wird.

Wählen Sie aus mehreren Tabellen in SQL aus

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

Schritt 4: Erstellen Sie eine abstrakte Klasse VegPizza, die auf die abstrakte Klasse Pizza erweitert wird.

 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. 

Schritt 5: Erstellen Sie eine abstrakte Klasse NonVegPizza, die auf die abstrakte Klasse Pizza erweitert wird.

 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. 

Schritt 6: Erstellen Sie nun konkrete Unterklassen SmallCheezePizza, MediumCheezePizza, LargeCheezePizza und ExtraLargeCheezePizza, die sich auf die abstrakte Klasse VegPizza erweitern.

 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. 

Schritt 7: Erstellen Sie nun auf ähnliche Weise konkrete Unterklassen SmallOnionPizza, MediumOnionPizza, LargeOnionPizza und ExtraLargeOnionPizza, die sich auf die abstrakte Klasse VegPizza erweitern.

 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 

Schritt 8: Erstellen Sie nun auf ähnliche Weise konkrete Unterklassen SmallMasalaPizza, MediumMasalaPizza, LargeMasalaPizza und ExtraLargeMasalaPizza, die sich auf die abstrakte Klasse VegPizza erstrecken.

 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 

Schritt 9: Erstellen Sie nun konkrete Unterklassen SmallNonVegPizza, MediumNonVegPizza, LargeNonVegPizza und ExtraLargeNonVegPizza, die sich auf die abstrakte Klasse NonVegPizza erweitern.

 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 

Schritt 10: Erstellen Sie nun zwei abstrakte Klassen Pepsi und Coke, die die abstrakte Klasse ColdDrink erweitern.

 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 

Schritt 12: Erstellen Sie nun konkrete Unterklassen SmallCoke, MediumCoke und LargeCoke, die sich auf die abstrakte Klasse Coke erweitern.

 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>  

Schritt 14: Erstellen Sie eine OrderBuilder-Klasse, die für die Erstellung der Objekte der OrderedItems-Klasse verantwortlich ist.

 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 

Schritt 15: Erstellen Sie eine BuilderDemo-Klasse, die die OrderBuilder-Klasse verwendet.

 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 

Ausgabe