和String达到一样的目的，节省空间

package com.test.pattern.flyweight;import java.util.Hashtable;abstract class Flyweight {    public abstract void operation();}class ConcreteFlyweight extends Flyweight {        private String str;    public ConcreteFlyweight(String str) {        this.str=str;    }    @Override    public void operation() {        System.out.println("Concrete---Flyweight: "+str);    }}//再定义一个工厂方法类class FlyweightFactory {    private Hashtable flyweights = new Hashtable();    public Flyweight getFlyweight(Object obj) {        Flyweight flyweight = (Flyweight)flyweights.get(obj);        if(flyweight == null) {            flyweight = new ConcreteFlyweight((String) obj);            flyweights.put(obj, flyweight);        }        return flyweight;    }    public int getFlyweightSize() {        return flyweights.size();    }}public class FlyweightTest {    FlyweightFactory factory = new FlyweightFactory();    Flyweight fly1,fly2,fly3,fly4,fly5;    public static void main(String[] args) {        System.out.println("The Flyweight Pattern");        FlyweightTest test = new FlyweightTest();        test.showFlyweight();    }    public FlyweightTest() {        fly1 = factory.getFlyweight("Google");        fly2 = factory.getFlyweight("Qutr");        fly3 = factory.getFlyweight("Google");        fly4 = factory.getFlyweight("Google");        fly5 = factory.getFlyweight("Google");    }    public void showFlyweight() {        fly1.operation();        fly2.operation();        fly3.operation();        fly4.operation();        fly5.operation();        int objSize = factory.getFlyweightSize();        System.out.println("objSize = " + objSize);    }}