FlyweightFactory.java

package com.cheng.zenofdesignpatterns.patterns.flyweight.common;

import java.util.HashMap;

/**
 * 享元工厂
 * 构造一个池日容器，同时提供从池中获得对象的方法
 */
public class FlyweightFactory {

	// 定义一个池容器
	private static  HashMap<String,Flyweight> pool= new HashMap<String,Flyweight>();
	
	// 享元工厂
	public static Flyweight getFlyweight(String Extrinsic){
		// 需要返回的对象
		Flyweight flyweight = null;
		// 在池中没有改对象
		if(pool.containsKey(Extrinsic)){
			flyweight = pool.get(Extrinsic);
		}else{
			// 根据外部状态创建享元对象
			flyweight = new ConcreteFlyweight1(Extrinsic);
			// 放置到池中
			pool.put(Extrinsic, flyweight);
		}
		return flyweight;
	}

}