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Thread: Subclassing Singleton class

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    Default Subclassing Singleton class

    When i googled with "Subclassing Singleton class" string, many of the blogs said, we cannot extend the Singleton class as the constructor is private. But when i tried it in eclipse, i am able to subclass a singleton class. Would like to know whether can we subclass a singleton class technically?? If yes, will it not create many instances of Singleton class?

    My singleton class
    class SingletonClass {

    private static SingletonClass singletonObject;
    /** A private Constructor prevents any other class from instantiating. */
    private SingletonClass() {
    // Optional Code
    }
    public static synchronized SingletonClass getSingletonObject() {
    if (singletonObject == null) {
    singletonObject = new SingletonClass();
    }
    return singletonObject;
    }
    public Object clone() throws CloneNotSupportedException {
    throw new CloneNotSupportedException();
    }
    }


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    Default Re: Subclassing Singleton class

    What happens when you try to compile and execute the testing code?

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    Default Re: Subclassing Singleton class

    There was a small mistake in my singleton class. You r rite, it gives compiler error "Implicit super constructor SingletonClass() is not visible for default constructor. Must define an explicit constructor".
    Thanks for ur help.

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