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

/**
 * A small extension to JPanel, meant to allow
 * the JPanel to support a tiling image background.
 * The tiled background is correctly drawn inside
 * any Border that the panel might have.  Note
 * that JTiledPanel containers are always opaque.
 * If you give the tiling image as null, then
 * JTiledPanel behaves exactly like an opaque
 * JPanel.
 */
public class JTiledPanel extends JPanel {
    private Image tileimage;
    private int tilewidth;
    private int tileheight;
    private Rectangle rb;
    private Insets ri;

    /**
     * Create a JTiledPanel with the given image.
     * The tile argument may be null, you can set it later
     * with setTileImage().  Note that a JTiledPanel is
     * always opaque.
     */
    public JTiledPanel(Image tile) {
        super();
        setTileImage(tile);
        setOpaque(true);
	rb = new Rectangle(0,0,1,1);
	ri = new Insets(0,0,0,0);
    }

    /**
     * Create a JTiledPanel with the given image and 
     * layout manager and double buffering status.  
     * Either or both of the first two arguments
     * may be null.
     */
    public JTiledPanel(Image tile, LayoutManager mgr, boolean isDB)
    {
        super(mgr, isDB);
        setTileImage(tile);
        setOpaque(true);
	rb = new Rectangle(0,0,1,1);
	ri = new Insets(0,0,0,0);
    }

    /**
     * Get the current tiling image, or null if there
     * isn't any right now.
     */
    public Image getTileImage() { return tileimage; }

    /**
     * Set the current tiling image.  To prevent tiling,
     * call this method with null.  Note that this method
     * does NOT call repaint for you; if you want the panel
     * to repaint immediately, you must call repaint() 
     * yourself.
     */
    public void setTileImage(Image tile) {
        tileimage = tile;
        tilewidth = 0;
        tileheight = 0;
    }

    

    /**
     * Paint this component, including the tiled
     * background image, if any.
     */
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        if (tileimage != null && tilewidth <= 0) {
            tileheight = tileimage.getHeight(this);
            tilewidth = tileimage.getWidth(this);
        }
        if (tileimage != null && tilewidth > 0) {
            Color bg = getBackground();
            getBounds(rb);
            Insets riv = getInsets(ri);
            rb.translate(riv.left, riv.top);
            rb.width -= (riv.left + riv.right);
            rb.height -= (riv.top + riv.bottom);
            Shape ccache = g.getClip();
            g.clipRect(rb.x, rb.y, rb.width, rb.height);
            int xp, yp;
            for(yp = rb.y; yp < rb.y + rb.height; yp += tileheight) {
                for(xp = rb.x; xp < rb.x + rb.width; xp += tilewidth) {
                    g.drawImage(tileimage, xp, yp, bg, this);
                }
            }
            g.setClip(ccache);
        }
    }

    /**
     * Small main to do a self-test.  Tiles with a image file
     * name taken from the command line.  For example, if you
     * have a directory named <tt>images</tt> and an image in it
     * named <tt>tile1.gif</tt> then you would run this test
     * main as  <tt>java JTiledPanel images/tile1.gif</tt>.
     */
    public static void main(String [] args) {
        if (args.length == 0) {
            System.out.println("Usage: java JTiledPanel imagefile");
            System.exit(0);
        }
        JFrame f = new JFrame("Test JTiledPanel " + args[0]);
        ImageIcon ic = new ImageIcon(args[0]);
        JTiledPanel jtp = new JTiledPanel(ic.getImage());
        jtp.setBorder(BorderFactory.createMatteBorder(3,4,5,6,Color.green));
        jtp.add(new JButton("Press Me!"));
        jtp.add(new JButton("Press Me Too!"));
        f.getContentPane().add(jtp, BorderLayout.CENTER);
        f.setSize(350,290);
        f.show();
        f.addWindowListener(new WindowAdapter() {
                public void windowClosing(WindowEvent we) {
                    System.exit(0);
                } });
    }
}