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Thread: static method in super class

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    Default static method in super class

    Suppose class A has many subclasses B, C, D,... (the names can be very irregular).
    Is there a way to implement a mathod

    public static newInstance(String xml)

    in class A such that when I say
    B.newInstance(anXml), the method in A will be invoked and returns an object of type B,
    while C.newInstance(aValue) will invoke the same method but returns an object of type C?

    Thanks for your help


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    Default Re: static method in super class

    Have you tried writing a simple test case and see what happens?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: static method in super class

    Quote Originally Posted by Norm View Post
    Have you tried writing a simple test case and see what happens?
    No. I don't know how. I used to program with ObjectC (cocoa), it's not hard doing such thing with
    ObjectC. And I'd like to port code to Java

    I heard that I need reflection functionalities in Java to do that.

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    Default Re: static method in super class

    Why are you trying to use a static method?
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: static method in super class

    Quote Originally Posted by Norm View Post
    Why are you trying to use a static method?
    Because I don't assume an object of type B (C, D,...) exists. I think any method creating objects is static...

    The reason I'd like to do things that way is that if I put newInstance method in each subclass, they look very similar and yet it's a big method, the resulting code will be very hard to maintain, and also ugly.

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    Default Re: static method in super class

    I think any method creating objects is static...
    You should do some research on static in java. Here's a page in the tutorial.
    Understanding Instance and Class Members (The Java™ Tutorials > Learning the Java Language > Classes and Objects)

    Instances of a class are created with the new statement.
    If you don't understand my answer, don't ignore it, ask a question.

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