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Thread: Inner class initialization and declaration

  1. #1
    Junior Member
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    Aug 2011
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    Default Inner class initialization and declaration


    When I do some coding on an existing project, I see some code like below inside a java method,

    class_name newClass = new class_name(){
    implementation of class_name...

    can anyone explain me what it is and what is purpose of doing this?


  2. #2
    Super Moderator Sean4u's Avatar
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    Jul 2011
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    Default Re: Inner class initialization and declaration

    It's an anonymous inner class. Sometimes you need a bare minimum of functionality that fulfils an interface and will only be instantiated once. GUI click-handlers are a perfect example. Usually every clickable control has a unique function - it would be a pain in the bum to write separate classes for each of them and offers a redundant facility: the option to instantiate more than one click-handling object.

  3. #3
    Crazy Cat Lady KevinWorkman's Avatar
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    Default Re: Inner class initialization and declaration

    Additionally, here's some recommended reading:
    JavaRanch Campfire - Getting in Touch with your Inner Class
    Anonymous inner classClass DefinitionJava Tutorial
    How to Ask Questions the Smart Way
    Static Void Games - GameDev tutorials, free Java and JavaScript hosting!
    Static Void Games forum - Come say hello!

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