如果大量对象只是某些细节不同,则可将这些不同抽离到外部,将相同的作为共享.那些不同的可作为参数传递.
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| package flyweight;
public class User {
private String name;
public User(String name) {
this.name = name;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
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| package flyweight;
public abstract class Website {
public abstract void option(User user);
}
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| package flyweight;
public class ConcreteWebsite extends Website {
private String type;
public ConcreteWebsite(String type) {
this.type = type;
}
@Override
public void option(User user) {
System.out.println("网站类型: " + type + ", 用户: " + user.getName());
}
}
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| package flyweight;
import java.util.concurrent.ConcurrentHashMap;
public class WebsiteFactory {
private ConcurrentHashMap<String, ConcreteWebsite> webs = new ConcurrentHashMap<>(5);
public ConcreteWebsite getWebsite(String type) {
if (webs.get(type) == null)
webs.put(type, new ConcreteWebsite(type));
return webs.get(type);
}
public int capacity() {
return webs.size();
}
}
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| package flyweight;
public class Main {
public static void main(String[] args) {
WebsiteFactory factory = new WebsiteFactory();
User 小明 = new User("小明");
ConcreteWebsite blog = factory.getWebsite("博客");
blog.option(小明);
User 小红 = new User("小红");
ConcreteWebsite community = factory.getWebsite("社区");
community.option(小红);
User 如花 = new User("如花");
ConcreteWebsite blog2 = factory.getWebsite("博客");
blog2.option(如花);
System.out.println(factory.capacity());
}
}
|
