frame setVisible(false) and dispose() can not kill the process

Question

I have following scenario (2 classes)

Frame1(next button)
Frame2(prev button, close button)
Frame1 opened (instance 1)
to go Frame1 - Frame2 (frame1.setVisible(false) and frame2.setVisible(true)) (instance 2)
to go Frame2 - Frame1 (frame2.setVisible(false) and frame1.setVisible(true)) (instance 3)
again Frame1 - Frame2 (frame1.setVisible(false) and frame2.setVisible(true)) (instance 4)

in above process 4 instances (If program opened then noted as instance)
now during close from Frame2, I m using frame1.dispose() and frame2.dispose()
here only 2 times instances are disposed.
But the problem is: still 2 instances are not disposed.
But only only one process is an alive. How is it possible?
In above scenario should I dispose all instances to kill the process ?

Answer 1

You consider to do like this if you do not want to go with CardLayout

Create a constructor in Frame1 with argument of Frame2 as shown below and store frame2 object locally.

public class Frame1{
    private Frame2 frame2Obj;
    public Frame1(Frame2 frame1Obj){
        this.frame2Obj = frame2Obj;
    }
    private openFrame1(){
         frame2Obj.setVisible(true);
         this.setVisible(false);
    }
}

Similarly create a constructor in Frame2 with argument of Frame1 as shown below and store frame1 object locally.

public class Frame2{
    private Frame1 frame1Obj;
    public Frame2(Frame1 frame1Obj){
        this.frame1Obj = frame1Obj;
    }
    private openFrame1(){
         frame1Obj.setVisible(true);
         this.setVisible(false);
    }
}

Now you will have only two instances.

Answer 2

• default value DefaultCloseOperation for JFrame is HIDE_ON_CLOSE

• have to set DefautlCloseOperation for JFrame with proper value (EXIT_ON_CLOSE)

• don't create an second or more JFrames, use CardLayout instead

• use JDialog instead another JFrame, in the case that there are real reasons