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programming of compositions (UML) example: forest - obelix - Mar-24-2019
Hi all,
I'd like to code down a correct structured example of some UML class compositions.
For now I suggest to use a "Forest" as example. But I am struggling how de correct class designs have to be.
Master class: Forest : exists 1 time
Children class 1: tree(s) : exists n times below
Children class 2 which is below class 1: Branch(es) : exists n times
[Forest]<>----[Tree]<>----[Branch]
So we have 3 different classes and all depend from its upper class. When upper class is destroyed, the children die.
My first question: do I need to design a "class in class" modell?
RE: programming of compositions (UML) example: forest - Yoriz - Mar-24-2019
class Branch:
pass
class Tree:
def __init__(self, branches):
self.branches = branches
class Forest:
def __init__(self, trees):
self.trees = trees
tree1 = Tree([Branch(), Branch()])
tree2 = Tree([Branch(), Branch()])
forest = Forest([tree1, tree2])
RE: programming of compositions (UML) example: forest - obelix - Mar-24-2019
Thanks !
OK, it means i put a list in the arguments of that class instances.
But what, when I dont know the number of trees resp. branches?
I 'd like to have a addTree resp. addBranch method in the classes.
Not sure if this is the correct way
RE: programming of compositions (UML) example: forest - Yoriz - Mar-24-2019
Yes just add a method to add items for example
class Tree:
def __init__(self, branches=None):
self.branches = branches or []
def add_branch(self, branch):
self.branches.append(branch)