I'm reading Effective Java by Joshua Bloch. I must say its a dense and complex book. The chapter on Methods Common to all objects (chapter 3) is proving hard for me to grasp as I've been programming for less than 3 years (1 year in java). I don't quite understand the concept of overriding the clone method appropriately. Can I get a simple to follow example of implementing clone, the right way as well as the wrong way? And why failing to invoke super.clone would cause a problem? what will happen?
Thank you in advance.
You should always use super.clone(). If you don't, and say just return new MyObject(this.x);, then that works fine for instances of MyObject. But if someone extends MyObject, it's no longer possible for them to get an instance of the right class when overriding your clone method. The one thing Object.clone does that you can't do a good job of yourself is creating an instance of the right class; the rest is just copying instance fields, which is drudgework you could have done yourself if you wanted.