1.单例模式之饿汉式

下面为两种饿汉式单例实现方式：

第一种：普通写法

package com.going.design.singleton.hungry;

/**
 * Created by renxf on 2021/1/2
 */
public class HungrySingleton {

    public static final HungrySingleton hungrySingleton = new HungrySingleton();

    private HungrySingleton(){};

    public static HungrySingleton getInstance(){
        return hungrySingleton;
    }

}

第二种：使用静态代码块

package com.going.design.singleton.hungry;

/**
 * Created by renxf on 2021/1/2
 * des:进一步优化
 */
public class HungryStaticSingleton {
    public static final HungryStaticSingleton hungrySingleton;//final 防反射攻击

    static {
        hungrySingleton = new HungryStaticSingleton();
    }
    private HungryStaticSingleton(){};

    public static HungryStaticSingleton getInstance(){
        return hungrySingleton;
    }
}

总结：

final：防止反射破坏单例

饿汉式缺点：可能会造成内存空间的浪费

标签：HungryStaticSingleton,hungrySingleton,饿汉,模式,final,static,单例,public,HungrySinglet
来源： https://blog.csdn.net/weixin_41474226/article/details/112514609