best way to access a parent object from a child object

Question

I am creating a population genetics simulation system in JRuby.

I have created classes such as Allele, Gene, Organism, Population.

A Population object contains multiple Organism objects (in an array), each Organism object contains multiple Genes, and so on.

Currently, it is very easy to know, for example, what Gene objects a certain Organism object has. However, if all I have is a Gene object, I do no know what Organism it belongs to.

One solution I have thought of is:

attr_accessor :name, :parent
def initialize(name, parent)
  @name = name
  @parent = parent #parent will be the parent object
end

If I do this, will @parent merely be a reference to the parent object in memory, or will it be a whole new object?

Is this the best way to do this? Is there another 'better' way of doing this?

Thanks!

Answer 1

JRuby will, as you suggest, just keep a reference to the object rather than creating a copy of it.

This is a perfectly sensible way to approach the problem. You are keeping a reference to an object you want to refer to!