import java.util.*;

//这个例子不太好

//Flyweight

interface Flyweight {

void action(int arg);

}

//ConcreteFlyweight

class FlyweightImpl implements Flyweight {

public void action(int arg) {

// TODO Auto-generated method stub

System.out.println("参数值:" + arg);

}

}

//FlyweightFactory

class FlyweightFactory {

private static Map flyweights = new HashMap();

public FlyweightFactory(String arg) {

flyweights.put(arg, new FlyweightImpl());

}

public static Flyweight getFlyweight(String key) {

if (flyweights.get(key) == null) {

flyweights.put(key, new FlyweightImpl());

}

return (Flyweight)flyweights.get(key);

}

public static int getSize() {

return flyweights.size();

}

}

//Test

public class DS11_Flyweight{

public static void main(String[] args) {

// TODO Auto-generated method stub

Flyweight fly1 = FlyweightFactory.getFlyweight("a");

fly1.action(1);

Flyweight fly2 = FlyweightFactory.getFlyweight("a");

System.out.println(fly1 == fly2);

Flyweight fly3 = FlyweightFactory.getFlyweight("b");

fly3.action(2);

Flyweight fly4 = FlyweightFactory.getFlyweight("c");

fly4.action(3);

Flyweight fly5 = FlyweightFactory.getFlyweight("d");

fly4.action(4);

System.out.println(FlyweightFactory.getSize());

}

}