Mixing images and shapes

Question

Hey all,
I have a bunch of objects that I want to paint on the screen and at the moment they all contain images so I paint them with g.drawImage. There may be a time however when it won't make sense to have an image. Like if I just need a green rectangle it might be better to have an actual green rectangle instead of trying to find an image of one. Since as far as I can tell there is no default draw method I imagine I'm stuck with drawImage. I'd rather not have an if statement to check for different types of shapes that I might want to draw. Is there a way to do what I'm trying to do (assuming I'm explaining what I'm trying to do well enough).
I thought maybe of maybe overriding the Graphics class and having a default draw method that can take anything and draw it but I'd imagine it would need to be able to convert shapes to images but I'm not really sure what the connection is between an Oval shape and just drawing an Oval with coordinates.
If I'm not doing a great job of explaining this, let me know and I'll try again. I guess I'm not really sure what it is I'm trying to do.

Answer 1

For the fun of it, and while Darryl was posting his reply, I hacked an example (from pieces of code that I already used in another project) where I defined an interface Renderable with a render(Graphics2D) method (more or less as Darryl suggested).
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.MultipleGradientPaint;
import java.awt.RadialGradientPaint;
import java.awt.Rectangle;
import java.awt.geom.Arc2D;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
public class RenderableTest {
    public static class Oval implements Renderable {
     private final Ellipse2D ellipse;
     private final Color color;
     public Oval(Color color, double width, double height) {
         this.color = color;
         ellipse = new Ellipse2D.Double(0, 0, width, height);
     @Override
     public double getHeight() {
         return ellipse.getHeight();
     @Override
     public double getWidth() {
         return ellipse.getWidth();
     @Override
     public void render(Graphics2D g2, double x, double y) {
         g2.setColor(color);
         ellipse.setFrame(x, y, ellipse.getWidth(), ellipse.getHeight());
         g2.fill(ellipse);
    public interface Renderable {
     public abstract double getHeight();
     public abstract double getWidth();
     public abstract void render(Graphics2D g2, double x, double y);
    public static class Smiley implements Renderable {
     private final BufferedImage image;
     public Smiley(int size, double smile) {
         if (smile < -1 || smile > 1) {
          throw new IllegalArgumentException(
               "Smile must be between -1 and +1");
         image = new BufferedImage(size, size, BufferedImage.TYPE_INT_ARGB);
         Graphics2D g = image.createGraphics();
         g.setRenderingHints(QualityHints.getHints());
         g.scale(size / 16.0, size / 16.0);
         paint(g, smile);
         g.dispose();
     @Override
     public double getHeight() {
         return image.getHeight();
     @Override
     public double getWidth() {
         return image.getWidth();
     @Override
     public void render(Graphics2D g2, double x, double y) {
         g2.drawImage(image, null, (int) Math.round(x), (int) Math.round(y));
     private void createPaint(Graphics2D g, Color middle) {
         g.setPaint(new RadialGradientPaint(8f, 8f, 7f, 5f, 3.2f,
              new float[] { 0f, 0.4f, 1f }, new Color[] { Color.WHITE,
                   middle, middle.darker() },
              MultipleGradientPaint.CycleMethod.NO_CYCLE));
     private void paint(Graphics2D g, double smile) {
         g.setStroke(new BasicStroke(1f,
              BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
         createPaint(g, Color.YELLOW.brighter());
         Ellipse2D.Double head = new Ellipse2D.Double(1, 1, 14, 14);
         g.fill(head);
         double boxHeight = 6;
         double smileHeight = boxHeight * Math.abs(smile);
         double smileY = 9.5 - (smile > 0 ? smileHeight / 2 : 0);
         Arc2D mouth = new Arc2D.Double(4, smileY, 8, smileHeight,
              smile <= 0 ? -5.0 : 175.0, 190.0, smile == -1
                   || smile == +1 ? Arc2D.CHORD : Arc2D.OPEN);
         if (smile == -1 || smile == +1) {
          createPaint(g, new Color(230, 230, 230));
          g.fill(mouth);
         createPaint(g, Color.BLACK);
         g.draw(mouth);
         g.draw(head);
         Ellipse2D.Double leftEye = new Ellipse2D.Double(4.3, 5.3, 2, 2);
         Ellipse2D.Double rightEye = new Ellipse2D.Double(9.7, 5.3, 2, 2);
         g.fill(leftEye);
         g.fill(rightEye);
    public static class Square implements Renderable {
     private final Rectangle2D rect;
     private final Color color;
     public Square(Color color, int size) {
         this.color = color;
         this.rect = new Rectangle2D.Double(0, 0, size, size);
     @Override
     public double getHeight() {
         return rect.getHeight();
     @Override
     public double getWidth() {
         return rect.getWidth();
     @Override
     public void render(Graphics2D g2, double x, double y) {
         g2.setColor(color);
         rect.setFrame(x, y, rect.getWidth(), rect.getHeight());
         g2.fill(rect);
    public static void main(String[] args) {
     SwingUtilities.invokeLater(new Runnable() {
         @Override
         public void run() {
          new RenderableTest().createGUI();
    private void createGUI() {
     JFrame frame = new JFrame("Test");
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
     frame.add(new JComponent() {
         private static final long serialVersionUID = 1L;
         private Renderable[] renderables = { new Oval(Color.CYAN, 64, 40),
              new Square(Color.MAGENTA, 64), new Smiley(64, -1),
              new Smiley(64, -.5), new Smiley(64, 0), new Smiley(64, .5),
              new Smiley(64, 1), };
         @Override
         public Dimension getPreferredSize() {
          double width = 0;
          double height = 0;
          for (Renderable renderable : renderables) {
              width += renderable.getWidth();
              height = Math.max(height, renderable.getHeight());
          Insets insets = this.getInsets();
          width = width + insets.left + insets.right;
          height = height + insets.top + insets.bottom;
          Dimension size = new Dimension();
          size.setSize(width, height);
          return size;
         @Override
         protected void paintComponent(Graphics g) {
          Rectangle innerArea = new Rectangle();
          SwingUtilities.calculateInnerArea(this, innerArea);
          g.translate(innerArea.x, innerArea.y);
          double x = 0, y = 0;
          for (Renderable renderable : renderables) {
              renderable.render((Graphics2D) g.create(), x, y);
              x += renderable.getWidth();
     frame.pack();
     frame.setLocationRelativeTo(null);
     frame.setVisible(true);
}Piet