Factory Pattern

package com.exmpl.factoryPattern;

public interface Animal {

       void getVoice();

}

package com.exmpl.factoryPattern;

public class Dog implements Animal {

       @Override

       public void getVoice() {

              System.out.println("Dog voice --- Bark Bark Bark Bark Bark");

       }

}

package com.exmpl.factoryPattern;

public class Cat implements Animal {

       @Override

       public void getVoice() {

              System.out.println("Cat voice --- Meow Meow Meow Meow Meow");

       }

}

package com.exmpl.factoryPattern;

public class Tiger implements Animal {

       @Override

       public void getVoice() {

              System.out.println("Tiger voice --- Growl Growl Growl Growl Growl");

       }

}

package com.exmpl.factoryPattern;

/*This is the factory class, which create specific animal based on animal type supplied.*/

public class AnimalFactory {

       final static String TIGER = "tiger";

       final static String DOG = "dog";

       final static String CAT = "cat";

       public Animal getAnimal(String animalType) {

              Animal returnAnimal = null;

              if (animalType != null) {

                     if (animalType.equalsIgnoreCase(TIGER)) {

                           returnAnimal = new Tiger();

                     } else if (animalType.equalsIgnoreCase(DOG)) {

                           returnAnimal = new Dog();

                     } else if (animalType.equalsIgnoreCase(CAT)) {

                           returnAnimal = new Cat();

                     }

              }

              return returnAnimal;

       }

}

package com.exmpl.factoryPattern;

public class ClientClass {

       public static void main(String[] args) {

              AnimalFactory animalFactory = new AnimalFactory();

              // Get tiger object from AnimalFactory and check it's voice.

              Animal animal1 = animalFactory.getAnimal("tiger");

              animal1.getVoice();

              // Get dog object from AnimalFactory and check it's voice.

              Animal animal2 = animalFactory.getAnimal("dog");

              animal2.getVoice();

              // Get cat object from AnimalFactory and check it's voice.

              Animal animal3 = animalFactory.getAnimal("cat");

              animal3.getVoice();

       }

}

Output è

Tiger voice --- Growl Growl Growl Growl Growl

Dog voice --- Bark Bark Bark Bark Bark

Cat voice --- Meow Meow Meow Meow Meow