Tech Kraft

Factory Pattern is one of the most common design patterns. In this example we will create a Factory interface, and concrete classes to implement this interface.

/*
 Class: ItemType.java
 */
 public interface ItemType{
   void doSomething();
 }

Item1.java

/*
 Class: Item1.java
 */
public class Item1 implements Factory{

@Override

public void doSomething(){

  System.out.println("My Item 1.");

}

}

Item2.java

/*
 Class: Item2.java
 */
 public class Item2 implements Factory{

@Override

public void doSomething(){

  System.out.println("My Item 2.");

}

}

Item3.java

/*
 Class: Item3.java
 */
 public class Item3 implements Factory{

@Override

public void doSomething(){

  System.out.println("My Item 3.");

}

}

ItemFactory.java

/*

Class: ItemFactory.java

*/

public class ItemFactory{

  public ItemType getItem(String itemType){

     it(itemType == null) {
        return null;
      }

      if(itemType.equalsIgnoreCase("Item1")){
         return new Item1();
      }else if(itemType.equalsIgnoreCase("Item2")){
         return new Item2();
      }else if(itemType.equalsIgnoreCase("Item3")){
         return new Item3();
      }
  return null;
  }

}

FactoryPatternDemo


public class FactoryPatternDemo{

    public static void main(String[] args) {

      ItemFactory itemFactory = new ItemFactory();

      ItemType someItem1 = itemFactory.getItem("Item1");

      someItem1.doSomething();

      ItemType someItem2 = itemFactory.getItem("Item2");

      someItem2.doSomething();

      ItemType someItem3 = itemFactory.getItem("Item3");

      someItem3.doSomething();

   }

}