prototypePattern.java

import java.util.Hashtable;
public abstract class Shape implements Cloneable {
   
   private String id;
   protected String type;
   
   abstract void draw();
   
   public String getType(){
      return type;
   }
   
   public String getId() {
      return id;
   }
   
   public void setId(String id) {
      this.id = id;
   }
   
   public Object clone() {
      Object clone = null;
      
      try {
         clone = super.clone();
         
      } catch (CloneNotSupportedException e) {
         e.printStackTrace();
      }
      
      return clone;
   }
}
public class Rectangle extends Shape {

   public Rectangle(){
     type = "Rectangle";
   }

   @Override
   public void draw() {
      System.out.println("Inside Rectangle::draw() method.");
   }
}
public class Square extends Shape {

   public Square(){
     type = "Square";
   }

   @Override
   public void draw() {
      System.out.println("Inside Square::draw() method.");
   }
}
public class Circle extends Shape {

   public Circle(){
     type = "Circle";
   }

   @Override
   public void draw() {
      System.out.println("Inside Circle::draw() method.");
   }
}
public class ShapeCache {
	
   private static Hashtable<String, Shape> shapeMap  = new Hashtable<String, Shape>();

   public static Shape getShape(String shapeId) {
      Shape cachedShape = shapeMap.get(shapeId);
      return (Shape) cachedShape.clone();
   }

   // Her Shape için veritabanı sorgusu çalıştığını varsay ve objeleri oluştur
   // shapeMap.put(shapeKey, shape);
   // Örneğin, 3 adet shape objesi oluşturduk
   
   public static void loadCache() {
      Circle circle = new Circle();
      circle.setId("1");
      shapeMap.put(circle.getId(),circle);

      Square square = new Square();
      square.setId("2");
      shapeMap.put(square.getId(),square);

      Rectangle rectangle = new Rectangle();
      rectangle.setId("3");
      shapeMap.put(rectangle.getId(), rectangle);
   }
}
public class PrototypePatternDemo {
   public static void main(String[] args) {
      ShapeCache.loadCache();
      Shape clonedShape = (Shape) ShapeCache.getShape("1");
      System.out.println("Shape : " + clonedShape.getType());
      Shape clonedShape2 = (Shape) ShapeCache.getShape("2");
      System.out.println("Shape : " + clonedShape2.getType());
      Shape clonedShape3 = (Shape) ShapeCache.getShape("3");
      System.out.println("Shape : " + clonedShape3.getType());
   }
}