public interface Flyweight {    public void operation(String state);}public class ConcreteFlyweight implements Flyweight {    private Character intrinsicState = null;    /**     * 构造函数，内蕴状态作为参数传入     *      * @param state     */    public ConcreteFlyweight(Character state) {        this.intrinsicState = state;    }    /**     * 外蕴状态作为参数传入方法中，改变方法的行为， 但是并不改变对象的内蕴状态。     */    @Override    public void operation(String state) {        // TODO Auto-generated method stub        System.out.println("Intrinsic State = " + this.intrinsicState);        System.out.println("Extrinsic State = " + state);    }}public class FlyweightFactory {    private Map
    
      files = new HashMap
     
      ();    public Flyweight factory(Character state) {        // 先从缓存中查找对象        Flyweight fly = files.get(state);        if (fly == null) {            // 如果对象不存在则创建一个新的Flyweight对象            fly = new ConcreteFlyweight(state);            // 把这个新的Flyweight对象添加到缓存中            files.put(state, fly);        }        return fly;    }}public class Client {    public static void main(String[] args) {        // TODO Auto-generated method stub        FlyweightFactory factory = new FlyweightFactory();        Flyweight fly = factory.factory(new Character('a'));        fly.operation("First Call");        fly = factory.factory(new Character('b'));        fly.operation("Second Call");        fly = factory.factory(new Character('a'));        fly.operation("Third Call");    }}
     
    

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