Check if there is an instance from specific class

Question

suppose i have i class with name FrmColor
and i want to write a program that show this Frame by clicking on a button like this
import FrmColor;
import java.awt.Button;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.Frame;
public class Test extends Frame
     private Button b;
     public static void main(String args[])
          new Test();
     public Test()
          super("Test");
          b = new Button("Show Color");
          b.addActionListener(new ActionListener(){
               public void actionPerformed(ActionEvent evt){
                    b_aciotnPerformed(evt);
     private void b_actionPerformed(ActionEvent evt)
          if there is an instance of FrmColor then
               bring FrmColor to Front
          else
               create an instance from this class
pleaze Help Me.

Answer 1

hi,
what you want is a static int variable called count which is incremented everytime the constructor is called:
public static int count = 0;In the constructor, have:
count++;and a static method to return this variable:
public static int getCount() {
    return count;
}You can then get this count:
FrmColor.getCount();This would be implemented in your code as follows:
private void b_actionPerformed(ActionEvent evt)
if(FrmColor.getCount() != 0)
    bring FrmColor to Front
else
    create an instance from this class