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Thread: quick question - new keyword

  1. #1
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    Default quick question - new keyword

    hi all, quick question here. dont recall seeing this in suns java tutorial.


    SwingUtilities.invokeLater(new Runnable() [B]{
    public void run() {
    new SwingDemo();
    }
    }[/B]);

    What exactly happens with the block following new's call to the constructor? Is this some sort of way of overriding the class' default implementation of the method "on the spot"? Just looking for a quick explanation for the syntax rule behind the bold block above.


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    Default Re: quick question - new keyword

    Whoops, I wasn't aware that Runnable was an interface that defined only one method. This leads me to another question:

    What happens when you try to instantiate an interface? Does it create an Object object which implements the interface?

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    Default Re: quick question - new keyword

    This is what's called an "anonymous class". basically, it's a class that has know name. It can be created from any abstract class or interface.

    You cannot directly create an abstract class or an interface. You must have either a class that extends it or implements it (respectively for class or interface).

  4. The Following User Says Thank You to helloworld922 For This Useful Post:

    bbr201 (July 19th, 2010)

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