*snip code*

Yes, don't consider this as written by a Graphics beginner, because *I*
wrote it and *you* have hacked it all to pieces. You should be more careful
about claiming ownership of what you didn't create. The code I gave you in
comp.lang.java.programmer worked perfectly. You seem to have taken it and
moved lines of code around at random. The reason it doesn't work is that you
moved my render call to the mousePressed method and my repaint calls to the
render method (which is in the wrong class, no less). You've created your
own unnecessary graphics context. And for some reason, you added a method
that's never used: erase(). Beyond not being used, there is no use for it at
all since there's *no need* to create a Graphics object (am I repeating
myself?), since your JPanel will provide you one via the paintComponent
method which I overrode and you removed entirely. Suffice to say, "your"
code is entirely screwed up just now. I suggest going back to the code that
I gave you (which I won't post again here) and examing why and how it works.
If you have questions, then by all means, ask. If you want, I'll even send
you another, heavily commented version to look over. Just think twice about
plagiarism next time.

gk:

If you see two replies, disregard the first one (fat finger).

You've got a couple of problems.  This biggest is that all drawing must
be done in the paintComponent() method.  I rewrote your code to make it
work more or less.  I also wrote you a simpler version to better explain
 how it needs to work.  There is some problem with the look and feel.
It leaves a tell-tale frame when I try it.  Probably needs to have
super.paintComponent() called to keep it clean.  If you do that though
it won't leave the old circles up.  To make that work you will need to
have a drawing surface separate from the component (eg. BufferedImage).
 If you want an example using the BufferedImage let me know.

Actually I tried putting the super.paintComponent() in my program and it
works fine just no preservation of the old circles.

knute...

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class TestContext extends JPanel implements MouseListener {

    public TestContext() {
    addMouseListener(this);
    }

    Circle circle;
    //this should draw a circle at the curent mouse coordinates
    public void mousePressed(MouseEvent e) {
    circle = new Circle(e.getX(), e.getY(), 50, Color.BLUE);
    //is this the problem? if i do a repaint instead of
    //the below 2 lines, nothing happens.
//    Graphics g = getGraphics();
//    circle.render(g);
    }
    public void mouseReleased(MouseEvent e) {

    }

    public void mouseClicked(MouseEvent e) {
    }

    public void mouseDragged(MouseEvent e) {
    }

    public void mouseMoved(MouseEvent e) {
    }

    public void mouseEntered(MouseEvent e) {
    }

    public void mouseExited(MouseEvent e) {
    }

    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        if (circle != null)
            circle.render(g);
        repaint();
    }
    //circle class that has methods to draw a cricle
    public class Circle {
        private int x;
        private int y;
        private int radius;
        private Color color;

    public Circle(int x, int y, int radius, Color color) {
        this.x = x;
        this.y = y;
        this.radius = radius;
        this.color = color;
        }

    public void render(Graphics g) {
        g.setColor(color);
        g.fillOval(x - radius, y - radius, radius*2, radius*2);
//        repaint();
        }

    public void erase(Graphics g) {
        g.dispose();
        }

    public void setPosition(int x, int y) {
        this.x = x;
        this.y = y;
        }
 }

 public static void main(String[] args) {
  JFrame.setDefaultLookAndFeelDecorated(true);//choose the look and feel
  JFrame frame = new JFrame();//set top level container
  TestContext tc = new TestContext();
  frame.getContentPane().add(tc, BorderLayout.CENTER);//add component
                              //class to container
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  frame.setBounds(100,100,500,500);
  frame.setVisible(true);
  }
}

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class test44 extends JPanel {
    int x,y;

    public test44() {
        addMouseListener(new MouseAdapter() {
            public void mousePressed(MouseEvent me) {
                x = me.getX();
                y = me.getY();
                repaint();
            }
        });
    }

    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.setColor(Color.BLUE);
        g.fillOval(x-25,y-25,50,50);
    }

    public static void main(String[] args) {
        test44 p = new test44();
        JFrame.setDefaultLookAndFeelDecorated(true);
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.getContentPane().add(p);
        f.setSize(320,240);
        f.show();
    }
}