I do Java programming and recently started learning Python via the official documentation. I see that we can dynamically add data attributes to an instance object unlike in Java:
class House:
pass
my_house = House()
my_house.number = 40
my_house.rooms = 8
my_house.garden = 1
My question is, in what situations is this feature used? What are the advantages and disadvantages compared to the way it is done in Java?
It can also be used when dynamically creating classes; see for instance this tutorial:
http://onlamp.com/pub/a/python/2003/04/17/metaclasses.html?page=1
or this one on Mix-ins, a programming technique that uses this capability to provide better encapsulation and modularity to object oriented code:
http://www.linuxjournal.com/article/4540
The first tutorial uses setattr(classname, "propertyname", value) instead of the classname.property = value syntax, but they are the same.
It's not often done from outside of the class unless the object is being used as a bucket of sorts. It's done an awful lot inside __init__() of course, to provide values to attributes that will be used elsewhere.
Oh, and speaking of Java...
