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Old 01-02-2008, 07:46 PM
eva eva is offline
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Overiding an abstract method
I tried to override an abstract method in a child class but complier complains and does not allow me to do this. Is it a rule or I am making some mistake?

Code:
public class Jupiter { public static void extractUsers() { } } public class Moon extends Jupiter { public void extractUsers() { } }
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Old 01-02-2008, 07:59 PM
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Your code didn't compile for me either, but the following did:
Code:
public class Jupiter { public static void extractUsers() { System.out.println("Superclass output"); } } public class Moon extends Jupiter { public static void extractUsers() { System.out.println("Subclass output"); } }
You can't override a static method as you did above, but the above code I posted does work. I'm not sure about your abstract method because I don't see one.

EDIT: see here for great info on the matter.

Last edited by CaptainMorgan : 01-02-2008 at 08:11 PM.
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Old 01-02-2008, 08:43 PM
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Abstract method
Hello, eva.

An abstract method can only be declared in an abstract class. Also, when you "override" an abstract method it is actually called implementing that method. Remember that an abstract method cannot do anything by itself.

Code:
public abstract class Jupiter { public abstract void extractUsers() { System.out.println("Superclass output"); } }
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Old 01-02-2008, 08:48 PM
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Quote:
Originally Posted by eva View Post
I tried to override an abstract method in a child class but complier complains and does not allow me to do this. Is it a rule or I am making some mistake?

Code:
public class Jupiter { public static void extractUsers() { } } public class Moon extends Jupiter { public void extractUsers() { } }
- PEACE
Method in Moon is hiding the static in implementation that is illegal. Try again with static in the extract user .. hope it helps .. tim is right for the abstract thing ..
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Old 01-03-2008, 10:30 AM
eva eva is offline
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Hi everyone,

Thanks for the explanation. I now realize that my code was horribly wrong. I learned a lot of things though.

Chao.
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Old 01-03-2008, 05:29 PM
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Quote:
Originally Posted by eva View Post
Hi everyone,

Thanks for the explanation. I now realize that my code was horribly wrong. I learned a lot of things though.

Chao.

Better to have tried and learned a lot, than not tried and learned nothing!

Glad you figured it out.
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