Can an object remove itself? How?

Question

I\'m trying to write a simple ball game, and there\'s several turns (ie., ball lives). The ball \"dies\" when it passes the bottom border of the screen. What I have so far w

Answer 1

It is possible to create a method in which the ball removes itself, but it's a bad thing to do. In order to remove itself from the screen, the Ball must have a reference to the screen. This creates a circular chain of references (Ball has a reference to screen, screen has a reference to Ball) which is going to make your design more complicated and your testing much more complicated.

Suicide is fine - the screen tells the ball to die, and the ball dies. But this is about removal of a relationship, not dying. The thing maintaining the relationship is the screen, and so it should be the thing doing the removal.

Also remember that the two do not necessarily have to happen together. The screen might want to keep a dead ball around for some reason, and it might want to remove a ball that isn't dead. Even if that doesn't happen in your app right now, allow for the possibility.