Java使用枚舉創建單例模式

[聲明]轉自：https://juejin.im/post/5d64ca62f265da03b638bb47

public class SingletonObject7 {


    private SingletonObject7(){

    }

    /**
     * 枚舉類型是線程安全的，並且只會裝載一次
     */
    private enum Singleton{
        INSTANCE;

        private final SingletonObject7 instance;

        Singleton(){
            instance = new SingletonObject7();
        }

        private SingletonObject7 getInstance(){
            return instance;
        }
    }

    public static SingletonObject7 getInstance(){

        return Singleton.INSTANCE.getInstance();
    }
}