全栈开发知识库

单例的最佳实现方式

public class Singleton {
    // Private constructor prevents instantiation from other classes
    private Singleton() { }

    /**
    * SingletonHolder is loaded on the first execution of Singleton.getInstance() 
    * or the first access to SingletonHolder.INSTANCE, not before.
    */
    private static class SingletonHolder { 
            public static final Singleton INSTANCE = new Singleton();
    }

    public static Singleton getInstance() {
            return SingletonHolder.INSTANCE;
    }
}

  • 邮箱 :charon.chui@gmail.com
  • Good Luck!