Inheriting from an abstract class

Hi all,
I'm using a certain graphics package and I need to modify a functionality of one of its classes called, say, PlainAxis. For this purpose I define a class MyAxis that derives from the class Axis which is the base class for PlainAxis as well. The Axis class is abstract; it has two abstract methods - draw() and copy(). I provide these two methods in MyAxis, so, it can be instantiated. Still I get the following error message during the compilation:
MyAxis should be declared abstract; it does not define draw() in Axis
Here is the command I'm executing (sgt.jar contains classes of the graphics package I'm using):
javac -g -classpath .:./sgt.jar *.java -d .
What am I doing wrong? Why does this error occure for the draw() method only?
Thank you for the help!

You probably didn't define draw() with the exactsame
method signatureBelieve me I did :) This was the first thing I
checked when I saw this error for the first time...
Any other suggestions? :)The possibilities that I can think of are (most of these have already been suggested):
1. you didn't define draw with the correct signature
2. you're not extending the class you think you're extending
3. you're not compiling the class you think you're compiling
4. there's a bug in your compiler
I'd say 3 is extremely unlikely. So without seeing your code, we can only guess, but I would guess #1.

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Say I have interface A and class B.
Now I creating class C extands B implements A
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bestam wrote:
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For example, if you were defining a few shapes and wanted common behavior to be available, you might define it as an interface:
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In the main class at runtime,I will be getting the
class name[B or C or D] to be instantiated. Also
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,but i want
want to know what is the differnece between a
interface and an abstract class with all the abstract
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Inheriting from an abstract class

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