How to get the color of a point?

Question

Hi.
I have a JPanel with some black circles draw on it (with drawOval() method), now i need to scan all the JPanel and search the black points and the withe ones.
I couldn't do this
i can found any method that give me the properties of a point in a JPanel.
can anyone tell where to look for this?, any method that controls the properties of a point?
PD: if is necessary, i can change the JPanel for a Canvas
TKS

Answer 1

hi. i make what you told me, but the getRGB() method is always giving me -1 as return.
here is my code, it's simple but i only need to make a matriz with this circles.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class GUI extends JFrame{
     private JPanel panel;
     private JFrame frame;
     public GUI () {
          frame = new JFrame("Puntos Espaciales.");
          JButton button = new JButton("Draw Circle");
          JButton button2 = new JButton("1");
          Container con = frame.getContentPane();
          panel = new JPanel();
          panel.setBorder(BorderFactory.createTitledBorder("Hello"));
          panel.setBackground(Color.WHITE);
          con.add(panel, BorderLayout.CENTER);
          con.add(button, BorderLayout.SOUTH);
          con.add(button2, BorderLayout.EAST);
          frame.setSize(800,600);
          frame.setVisible(true);
          button.addActionListener(new ActionListener() {
              public void actionPerformed(ActionEvent event) {
                 Graphics g = panel.getGraphics();
                 g.setColor(Color.BLACK);
                   g.fillOval(50, 50, 50, 50);
          button2.addActionListener(new ActionListener() {
              public void actionPerformed(ActionEvent event) {
                 BufferedImage image = new BufferedImage(panel.getWidth(), panel.getHeight(), BufferedImage.TYPE_INT_RGB);
                 Graphics2D g2d = image.createGraphics();
                 panel.paint( g2d );
                 g2d.dispose();
                 System.out.println("5,5" + image.getRGB(5, 5));
                 System.out.println("50,50" + image.getRGB(50, 50));
     public static void main(String[] args) {
          GUI gui = new GUI();
}tks for your help
PD: sorry for the delay