Thread: where to put list of objects method OOP

First scenario:

The Person class represents a single person. Why should it have to keep track of every Person which has been instantiated? It shouldn't. Different people are going to be instantiated for different reasons and there doesn't need to be a "master list" accessible from the Person class. There are technical implications on why it shouldn't (not unsolvable, just unnecessary problems to have to think about), but the above is the main reasons.

Second scenario:

A WorkCenter's representation may contain a list of People who work there. In this case it is perfectly valid for it to keep track of what people are related to a given WorkCenter and a getPeople() method is a great way to retrieve the list of workers.

It depends on what your application is doing. In general I don't think it's useful to have a list of every instance created of a particular class. It plays havoc on memory management systems because the garbage collector has no idea when a particular instance is ready to be destroyed.

Wherever people are being used should keep track of what people instances they are interacting with (similar to case 2).

What problem are you trying to solve that would involve keeping a global list of people instances? There may be a better way to structure your program to avoid it.