Border on an rounded JTextField?

[Andreas Bystrom]

I've found this example of how to make a JTextField rounded in the corners and now I wonder if someone could help me to add an border that is also rounded?
The code for the rounded textfield looks like this:

  
  public class RoundField extends JTextField {
    public RoundField(int cols) {
        super(cols);
        // We must be non-opaque since we won't fill all pixels.
        // This will also stop the UI from filling our background.
        setOpaque(false);
        // Add an empty border around us to compensate for
        // the rounded corners.
        setBorder(BorderFactory.createEmptyBorder(3, 5, 3, 5));
    }
    protected void paintComponent(Graphics g) {
        int width = getWidth();
        int height = getHeight();
        // Paint a rounded rectangle in the background.
        g.setColor(getBackground());
        g.fillRoundRect(0, 0, width, height, 8, 8);
        // Now call the superclass behavior to paint the foreground.
        super.paintComponent(g);
    }
}

How is it possible to do a border on this JTextField that is rounded as well?
Thanks in advance!
// Andreas

[Nathan Pruett]

Here's how you would do it...

import java.awt.Component;
import java.awt.Graphics;
import java.awt.Insets;
 
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.border.AbstractBorder;
 
public class RoundField extends JTextField {
 
    public RoundField(int cols) {
        super(cols);
        
        // We must be non-opaque since we won't fill all pixels.
        // This will also stop the UI from filling our background.
        setOpaque(false);
           
        // Add an empty border around us to compensate for
        // the rounded corners.
        setBorder(BorderFactory.createEmptyBorder(3, 5, 3, 5));
    }
    
    protected void paintComponent(Graphics g) {
        int width = getWidth() - getInsets().left - getInsets().right;
        int height = getHeight() - getInsets().top - getInsets().bottom;
           
        // Paint a rounded rectangle in the background.
        g.setColor(getBackground());
        g.fillRoundRect(getInsets().left, getInsets().top, width, height, 8, 8);
         
        // Now call the superclass behavior to paint the foreground.
        super.paintComponent(g);
    } 
     
    public static void main( String[] args ) {
        JFrame f = new JFrame( "Test RoundField" );
        
        JPanel p = new JPanel();
        RoundField rf = new RoundField( 10 );
        rf.setBorder( BorderFactory.createCompoundBorder( new RoundedBorder(), rf.getBorder() ) );
        p.add( rf );
        p.setBorder( new RoundedBorder() );
        f.getContentPane().add( p );
        
        f.setBounds( 300, 300, 300, 300 );
        f.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
        f.setVisible( true );
    }
    
    private static class RoundedBorder extends AbstractBorder {
        
        public Insets getBorderInsets( Component c, Insets insets ) {
            insets.left = insets.top = insets.right = insets.bottom = 18;
            return insets;
        }
        
        public void paintBorder( Component c, Graphics g, int x, int y,
                int width, int height) {
            int w = width;
            int h = height;
            
            g.translate(x, y);
            g.setColor( c.getBackground().darker() );
            g.drawRoundRect( 0, 0, w-2, h-2, 8, 8 );
            g.translate(-x, -y);
        }
        
        public boolean isBorderOpaque() {
            return true;
        }
    }
}