Imprimir Swing

import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import java.awt.print.PrinterException;
import java.awt.print.PrinterJob;

public class interfaz extends javax.swing.JFrame {

public class interfaz extends javax.swing.JFrame implements Printable {

    public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
        throw new UnsupportedOperationException("Not supported yet.");
    }

public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException  {
        if (pageIndex == 0)
        {
            Graphics2D g2d = (Graphics2D) graphics;
            g2d.translate(pageFormat.getImageableX(), pageFormat.getImageableY());
            this.printAll(graphics);
            return PAGE_EXISTS;
        }
        else
            return NO_SUCH_PAGE;        
    }

 private void cmdPrintActionPerformed(java.awt.event.ActionEvent evt) {
        //Crea y devuelve un printerjob que se asocia con la impresora predeterminada
        //del sistema, si no hay, retorna NULL
        PrinterJob printerJob = PrinterJob.getPrinterJob();
        //Se pasa la instancia del JFrame al PrinterJob
        printerJob.setPrintable(this);
        //muestra ventana de dialogo para imprimir
        if ( printerJob.printDialog())
        {
            try {
                printerJob.print();
            } catch (PrinterException ex) {
            System.out.println("Error:" + ex);
            }
        }
    }