topic Static Methods in Application Development and Automation Discussions

Static Methods

arpitgoyal — Wed, 18 Jun 2008 08:04:11 GMT

Why are static methods defined in super class cant be reimplemented in sub-classes?

Any workaround for this?

Regards,

Arpit.

Re: Static Methods

Former Member — Wed, 18 Jun 2008 09:32:55 GMT

Hi Aprit ,

So as to avoid method overidding.

Static method::::

It is a class method

Accessed using class name.method name

For using static methods, creation of instance is not necessary

A static method can only access other static data and methods. It cannot access non-static members

Now if you go implementing it in subclass this has to be done before implementing

HIDDING :

See if a sublcass defines a class method (static method) with the same signature as a class method in the super class the method in the subclass Hides the one in super-class

Hiddding a static method of a super class looks like overidiing an instance method of a superclass.When you overide an instance method we'll have the runtime polymorphism but when we do it with static method there is no runtime.

cheers

Mohinder Singh Chauhan

Re: Static Methods

Former Member — Wed, 18 Jun 2008 09:36:47 GMT

Hi,

Static Methods are Class Specific and not instance specific. Therefore whether it a parent class or the child class the definition of the method cannot be different. Such methods do not need the instance of the class.

I am not able to clearly understand your requirement. I am not sure of the Work around but you can have a static method in your class that can be called. Here you can decide to call either the super class or have your own implementation.

Regards,

Saurabh

Re: Static Methods

Former Member — Thu, 19 Jun 2008 04:01:02 GMT

Hi,

There is only one static component per program context. To summarize:

Static Components and Inheritance

• A class that defines a public or protected static attribute shares this attribute

with all its subclasses

• Static methods cannot be redefined

Static methods cannot be abstract because they cannot be redefined.

Re: Static Methods

joerg_wegener — Thu, 19 Jun 2008 12:24:07 GMT

Hello,

as was described by the other posters on this thread, the fact that static methods cannot be overridden is a design decision underlying ABAP Objects.

If you want to inherit from an ABAP class in the standard, I don't have a solution. If you are free to change things because they are in your own coding, I can propose a workaround.

What you can do is to change your class so that the static methods become instance methods of a singleton. Object creation can be done in the class constructor. Now you can inherit from the singleton class and override methods normally.

Hope this helps

Joerg