设计模式--结构型--享元模式

设计模式--结构型--享元模式：

针对案例，咖啡馆卖咖啡，咖啡品种20种类以下，订单可能有500个  没必要生成500个对象

package com.xy;

public interface FlyWeight {
	void sell();
}

package com.xy;

public class FlyWeightImpl implements FlyWeight {

	public String coffeeName;

	public FlyWeightImpl(String coffeeName) {
		this.coffeeName = coffeeName;
	}

	@Override
	public void sell() {
		// TODO Auto-generated method stub
		System.out.println("销售出的咖啡是：" + coffeeName);
	}

}

package com.xy;

import java.util.HashMap;
import java.util.Map;

public class CoffeeFactory {
	
	private static Map coffees= new HashMap<String, FlyWeight>();
	
	public FlyWeight getCoffee(String name){
		FlyWeight coffee = (FlyWeight) coffees.get(name);
		if(null==coffee){
			coffee =new FlyWeightImpl(name);
			coffees.put(name, coffee);
		}
		
		return coffee;
	}
	
	
	
	public static void main(String[] args) {
		CoffeeFactory factory = new CoffeeFactory();
		factory.getCoffee("摩卡").sell();
		factory.getCoffee("摩卡").sell();
		
	}
	
	
}

销售出的咖啡是：摩卡
销售出的咖啡是：摩卡