Home/ Questions/Q 8928193
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-15T08:22:50+00:00

Lets say we have an object (A), which should execute a method of another

  • 0

Lets say we have an object (A), which should execute a method of another object (B) which is not in the scope of the object (A) itself, nor it is in the scope of its members.

The overcome this problem I might one of the following methods:

  • Store a reference to the object with in any object that might use it, might led to a memory leak

  • Create getters for any object that I might need to use and use them like that (which is probably not the best practice).

    anObject.getABC().getDEF().getHIG().DoSomething();

  • Define some of the object as a single tone, this might be a good solution but whenever I use a libery overrding it might be a pain, its subclasses wont work with the over ridden one.

  • static members, probably the worst way.

My question: What is the best way to do it, and what should be taken into consideration, while maintain object oriented code?

(The questions refers to general OOP, however I prefer code examples in JAVA)

Examples:

  • users clicks something on the menu this should affect something that is not related to the menu nor anything closely related to it.for

  • A class that has a consume method which should free its memory should access objects that might hold is reference but not directly related to it.For instance, there is a car object which is drawn on a canvas should delete itself from it and from array that hold a list of cars that doesn’t have any relational to the GUI thread.

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    The Law of Demeter says: Don’t talk to strangers.

    If A needs to call a method of B, then B should be a direct dependency of A. If B is in fact not a direct dependency of A, but is a transitive dependency, i.e. A depends on C, which depends on D, which depends on B, then A should call a method of C, which would call a method of D, which would call the method of B:

    A --> C --> D --> B

    Reading your examples, it looks like you’re looking for the Observable/Observer method. For example: when you click on a menu, the menu should just call a method of its observers (or listeners, in Swing/AWT terminology), which are instances of an interface. The listener would register itself to the menu, in order to be notified of a menu click.

    • 0