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Thread: How to access derived class field values?

  1. #1
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    Default How to access derived class field values?

    Hi there.
    I want to access derived class field values. I can access field names with my code but for the values Its necessary to create a class instance.
    I don't know how to do. look at my code:
    for (Field f : getClass().getDeclaredFields()){
    	fieldNames += f.getName()+",";
    }
    How to access values?


  2. #2
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    Default Re: How to access derived class field values?

    I have no idea what you are asking. Please elaborate and maybe provide some more code or create a SSCCE.
    Improving the world one idiot at a time!

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    Default Re: How to access derived class field values?

    Quote Originally Posted by Junky View Post
    I have no idea what you are asking. Please elaborate and maybe provide some more code or create a SSCCE.
    public class a{
      // here I want to read the value of name or f1 or f2 or every other field values from derived classes
    }
    public class b extends a{
      public string name;
    }
    public class c extends a{
      public string f1;
      public string f2;
    }

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    Default Re: How to access derived class field values?

    No! That is absolutely the wrong way to go about it. A parent class should be stand alone. By that I mean that if the child class did not exist then the parent class should be able to compile and execute. If you think you need the parent class to have access to instances of the child class then you have a bad design.
    Improving the world one idiot at a time!

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    Default Re: How to access derived class field values?

    Quote Originally Posted by Junky View Post
    No! That is absolutely the wrong way to go about it. A parent class should be stand alone. By that I mean that if the child class did not exist then the parent class should be able to compile and execute. If you think you need the parent class to have access to instances of the child class then you have a bad design.
    No man! it's the best idea which I've implemented in dot net.
    In dot net I can do this, I just want to know how to do it in Java.

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    Default Re: How to access derived class field values?

    You ask for advice and when you don't hear what you want you just ignore it!
    Improving the world one idiot at a time!

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    Default Re: How to access derived class field values?

    Quote Originally Posted by Junky View Post
    You ask for advice and when you don't hear what you want you just ignore it!
    I don't need advice, I just need solution!

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    Default Re: How to access derived class field values?

    I don't need advice, I just need solution!
    That's one of the better quotes I've heard! Thanks for brightening my day, even though it may have left me a tiny bit sadder (but just for you).

  9. The Following User Says Thank You to GregBrannon For This Useful Post:

    Kewish (October 2nd, 2013)

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    Default Re: How to access derived class field values?

    Quote Originally Posted by GregBrannon View Post
    That's one of the better quotes I've heard! Thanks for brightening my day, even though it may have left me a tiny bit sadder (but just for you).
    Come on, cheer up! The OP also uses a hammer to screw

  11. The Following User Says Thank You to PhHein For This Useful Post:

    Kewish (October 2nd, 2013)

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