Thread: OutOfMemoryError (Java heap space)

whats wrong with this error?

[COLOR="Red"]Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
        at java.util.Arrays.copyOf(Arrays.java:2760)
        at java.util.Arrays.copyOf(Arrays.java:2734)
        at java.util.ArrayList.ensureCapacity(ArrayList.java:167)
        at java.util.ArrayList.add(ArrayList.java:351)
        at java.awt.Container.addImpl(Container.java:1054)
        at java.awt.Container.add(Container.java:365)
        at xTestx.NewMain.main(NewMain.java:69)[/COLOR]

this is the code

package xTestx;
 
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Container;
 
/**
 *
 * @author
 */
 
public class NewMain {
 
    public static void main(String[] args) {
 
        JFrame window;
        Container container;
 
        window = new JFrame();
        window.setSize(400, 400);
        window.setLocation(200, 300);
        window.setVisible(true);
 
        while (true) {
 
            JPanel panel = new JPanel() {
            Color color;
 
                @Override
                public void paintComponent(Graphics g) {
 
                    super.paintComponent(g);
 
                    int x = (int) (Math.floor(Math.random() * 3) + 1);
 
                    switch (x) {
 
                        case 1:
 
                            color = Color.BLACK;
                            break;
 
                        case 2:
 
                            color = Color.BLUE;
                            break;
 
                        case 3:
 
                            color = Color.GREEN;
                            break;
 
                        default:
 
                            color = Color.PINK;
                            break;
                    }
 
 
                    g.setColor(color);
                    g.fillRect(50, 50, 50, 50);
                }
            };
 
            container = window.getContentPane();
            container.add(panel);
        }
    }
}

i just to make a simple program that demonstrates a shape that continuesly change color while running..

The problem with the code posted is that you are continuously creating JPanels in a while loop and keeping a reference to those JPanels by calling the add, so it'll eventially max out. You should do this another way, such as creating a SwingTimer to update a single JPanel after a certain interval (How to Use Swing Timers (The Java™ Tutorials > Creating a GUI With JFC/Swing > Using Other Swing Features))
Somwthing along the lines like this:

public class NewMain extends JPanel implements ActionListener{
 
	public static void main(String args[]){
		NewMain nm = new NewMain();
 
		SwingTimer timer = new SwingTimer( 60, nm );//update every 60 milliseconds
		timer.start();
	}
 
	public void actionPerformed(ActionEvent e){
		////do the drawing then call repaint()
	}
}

hmm i like that one.. tnx for that sir... im gonna post any further questions if i encounter some problems again