The following abstract class don't have any abstract method?

Question

Mage_Catalog_Block_Product_Abstract

this class don't have any abstract method, what is the use of declaring this class as abstract?

is there any coding standard/genetic involved?

Answer 1

In order to have an abstract class, you don't need to have abstract methods in it. you can just declare it abstract.
On the other hand, if you have an abstract method in it, the class HAS TO BE abstract.
In this case, that specific class is not meant to be instantiated. That's why is declared as abstract.
It is used only as a parent class that holds common logic for other classes that get to be instantiated.