享元模式(Flyweight):运用共享技术有效地支持大量细粒度的对象。
package flyweight;
/**
* 享元模式(Flyweight)
* 用户类
*/
public class User {
private String name;
public String getName() {
return name;
}
public User(String name) {
this.name = name;
}
}
package flyweight;
/**
* 享元模式(Flyweight)
* 网站抽象类
*/
public abstract class WebSite {
public abstract void use(User user);
}
package flyweight;
/**
* 享元模式(Flyweight)
* 具体网站类
*/
public class ConcreteWebSite extends WebSite {
private String name;
public ConcreteWebSite(String name) {
this.name = name;
}
@Override
public void use(User user) {
System.out.println("网站分类:" + name + " 用户:" + user.getName());
}
}
package flyweight;
import java.util.Hashtable;
/**
* 享元模式(Flyweight)
* 网站工厂类
*/
public class WebSiteFactory {
private Hashtable flyweights = new Hashtable();
// 获得网站分类
public WebSite getWebSiteCategory(String key) {
if (!flyweights.contains(key)) {
flyweights.put(key, new ConcreteWebSite(key));
}
return (WebSite) flyweights.get(key);
}
// 获得网站分类总数
public int getWebSiteCount() {
return flyweights.size();
}
}
package flyweight;
/**
* 享元模式(Flyweight)
* 客户端main方法
*/
public class Client {
public static void main(String[] args) {
WebSiteFactory f = new WebSiteFactory();
WebSite fx = f.getWebSiteCategory("产品展示");
fx.use(new User("小菜"));
WebSite fy = f.getWebSiteCategory("产品展示");
fy.use(new User("大鸟"));
WebSite fz = f.getWebSiteCategory("产品展示");
fz.use(new User("娇娇"));
WebSite fl = f.getWebSiteCategory("博客");
fl.use(new User("老顽童"));
WebSite fm = f.getWebSiteCategory("博客");
fm.use(new User("桃谷六仙"));
WebSite fn = f.getWebSiteCategory("博客");
fn.use(new User("南海鳄神"));
System.out.println("得到网站分类总数为" + f.getWebSiteCount());
}
}