享原模式

介紹

享原模式：是結構性模式，主要用於減少創建對象的數量，以減少內存佔用和提高性能。 享元模式和原型模式的區別：原型模式爲了快速創建對象，而享原模式是爲了對象的複用

UML

實現代碼

public class FlyweightPatternDemo {
	public static void main(String[] args) {
		Shape circle = ShapeFactory.getShape("circle");
		circle.drow();
		ShapeFactory.getShape("circle");
	}
}

/**
 * 對象存儲工廠
 */
public class ShapeFactory {
	public static final Map<String,Shape> shapeMap = new HashMap<>();
	
	public static Shape getShape(String shapeName){
       Shape shape = shapeMap.get(shapeName);
       if(shape == null){
    	   if("circle".equals(shapeName)){
    		   shape = new Circle();
    		   shapeMap.put("circle", shape);
    	   }
       }
       return shape;      
	}
}

public interface Shape {
	void drow();
}

class Circle implements Shape{
	public Circle(){
		System.out.println("--- create circle ----");
	}
	@Override
	public void drow() {
		System.err.println("====circle====");
	}
}