Question

Given two classes, creating an object of each class in one another results in StackOverflow Exception. It is a JAVA project btw.

There are multiple classes in my projects and for using the other classes, I thought i would create objects of the other class and use it.

Say i have class Main and class GUI. I have created object of GUI in MAIN and initialized it. Similarly i have created an object of MAIN in GUI and initialized it.

Now this gives me a Stack Overflow Exception as the the constructor calls are going deep into recursion.

How do i go about it?

One possible solution i can think of is making variables and methods of one class STATIC.

Any other solution? Please suggest.

Answer 1

You should be passing an instance of one of you classes into the constructor of the other class.

public class Main {
   private final GUI gui;
   Main() {
      gui = new GUI(this);
   }
}

public class GUI {
   private final Main main;
   public GUI(Main main) {
      this.main = main;
   }
}

You could also use setters instead of constructors. I don’t like this option as much, because you lose the ability to make your variables final.

public class Main {
   private GUI gui;
   Main() {
   }
   public void setGui(GUI gui) {
      this.gui = gui;
   }
}

public class GUI {
   private Main main;
   public GUI() {
   }
   public void setMain(Main main) {
      this.main = main;
   }
}

public static void main(String[] args) {
   Main main = new Main();
   GUI gui = new GUI();
   main.setGui(gui);
   gui.setMain(main);
}