Brtdku

I was coding my AI project in java while I ran into this problem. I first generate the environment of some game using class "Pasture". Then the intelligent agent which is written in class "Shepherd" ask's some questions from the "Pasture" class using it's public interface and then moves based on the results. Now, when certain conditions hold, the game ends and I can simply print the score and then call System.exit(0) to end the program. But, I want to start a new game when the game ends, instead of just ending the whole program. Now I need to destroy the "Shepherd" class to end the agent and then start a new game. I know that java classes has destructors. The question is:
can I call the destructor of another java class(in this case the class "Shepherd") inside another class(in this case the class "Pasture")?
and How can I write a destructor method? What is the syntax?

Thanks, everyone. I got it. I was wrong about destructors. I just thought that like c++, java also has destructors.

Now I need to destroy the "Shepherd" class to end the agent and then start a new game. I know that java classes has destructors.

You have misunderstood something fairly fundamental:

1. Java doesn't have destructors. You might be confusing destructors with finalizers. These are methods that are called after the GC has decided to delete an object. (This is an oversimplification ... but the real point is that finalizers are not relevant to this problem. In fact, there very few cases where finalizers are relevant.)




2. You can't destroy objects. Objects are destroyed by the garbage collector when they are no longer needed. More specifically, they are destroyed when they are unreachable; i.e. when they can no longer influence the execution of the program.

So what do you do?

First of all, forget about "destroying" objects. Instead think about how to prepare for the next game. There are two approaches.

1. You could implement a reset() or similar method on all "game" objects that need to be reset / reinitialized when your start a new game.




2. You could simply drop all of the relevant "game" object on the floor and create new ones. (The GC will take care of the garbage.)

Or you could use a combination of the two approaches; e.g. reset the Pasture object to its initial state and discard / recreate the Shepard, Sheep and so on.

There are no destructors in java that you can program or call. To tell the garbage collector that you are not using an object anymore you can set it to null

myObject = null;

If you have some resources that needs to be closed/freed you can of course create your own destruct method but you have to call it manually

myObject.closeResources();

myObject = null;

Or if you want to reuse an object you could have a reset method that sets the object in the same state as it was when it was first created you could make your constructor call the same method and then you do it manually.

public class MyClass {

    public MyClass() {

        this.reset();

    }

}



MyClass myObject = new MyClass();

...



myObject.reset();