我是想连接打印机打印但点了print button 后打印界面就出来了 但不能完成打印 后果是会一直运行无法退出除非重启电脑

import java.awt.*;
import java.awt.print.*;public class PrintActivityReport extends javax.swing.JDialog implements Printable
{
// Variables declaration - do not modify
private javax.swing.JCheckBox followUpRepCheck;
private javax.swing.JCheckBox incidenceRepCheck;
private javax.swing.JCheckBox informationCheck;
private javax.swing.JButton printButton;
private javax.swing.JLabel header;
private javax.swing.JLabel subHeader;
private javax.swing.JLabel locationTab;
private javax.swing.JLabel forPeriod;private javax.swing.JLabel offSign;
private javax.swing.JLabel traineeSign;private javax.swing.JPanel ActivityReport;
private javax.swing.JScrollPane incidentTextAreaScrollPane;
private javax.swing.JTextArea incidentTextArea;
private javax.swing.JTextPane clientTextPane;
// End of variables declaration// Creates object For table
// PrintViewActivity printContentPane;/** Creates new form PrintActivityReport */
public PrintActivityReport(java.awt.Frame parent, boolean modal) {
super(parent, modal);
initComponents();
}// initComponents method 
private void initComponents() {
ActivityReport = new javax.swing.JPanel();
header = new javax.swing.JLabel();
subHeader = new javax.swing.JLabel();
locationTab = new javax.swing.JLabel();
forPeriod = new javax.swing.JLabel();
offSign = new javax.swing.JLabel();
traineeSign = new javax.swing.JLabel();
printButton = new javax.swing.JButton();
incidenceRepCheck = new javax.swing.JCheckBox();
informationCheck = new javax.swing.JCheckBox();
followUpRepCheck = new javax.swing.JCheckBox();
clientTextPane = new javax.swing.JTextPane();
incidentTextAreaScrollPane = new javax.swing.JScrollPane();
incidentTextArea = new javax.swing.JTextArea();setDefaultCloseOperation(javax.swing.WindowConstants.DISPOSE_ON_CLOSE);
ActivityReport.setLayout(null);
ActivityReport.setBackground(new java.awt.Color(255, 255, 255));setTitle("Activity Report");
setSize(700,720);
java.awt.Toolkit toolkit = java.awt.Toolkit.getDefaultToolkit(); 
java.awt.Dimension dimension = toolkit.getScreenSize();
setLocation(
dimension.width / 2 - 700 / 2,
dimension.height / 2 - 720 / 2
);header.setFont(new java.awt.Font("Arial", 1, 14));
header.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
header.setText("CrimeTek Security Services");
ActivityReport.add(header);
header.setBounds(230, 10, 230, 17);subHeader.setBackground(new java.awt.Color(255, 255, 255));
subHeader.setFont(new java.awt.Font("Arial", 1, 12));
subHeader.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
subHeader.setText("Daily Activity Report");
ActivityReport.add(subHeader);
subHeader.setBounds(250, 30, 160, 20);locationTab.setFont(new java.awt.Font("Arial", 1, 12));
locationTab.setText("Location : G-1");
ActivityReport.add(locationTab);
locationTab.setBounds(20, 50, 80, 20);forPeriod.setFont(new java.awt.Font("Arial", 1, 12));
forPeriod.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
forPeriod.setText("From : 2005-11-08 To : 2005-11-21");
forPeriod.setAutoscrolls(true);
ActivityReport.add(forPeriod);
forPeriod.setBounds(430, 50, 220, 15);offSign.setBackground(new java.awt.Color(255, 255, 255));
offSign.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
offSign.setText("Officer Signature :");
ActivityReport.add(offSign);
offSign.setBounds(10, 610, 150, 14);traineeSign.setBackground(new java.awt.Color(255, 255, 255));
traineeSign.setText("2nd Officer or Trainee Signature :");
ActivityReport.add(traineeSign);
traineeSign.setBounds(384, 610, 200, 30);printButton.setBackground(new java.awt.Color(255, 255, 255));
printButton.setText("Print");
ActivityReport.add(printButton);
printButton.setBounds(270, 620, 100, 20);printButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
printActionPerformed(evt);
}
});incidenceRepCheck.setBackground(new java.awt.Color(255, 255, 255));
incidenceRepCheck.setFont(new java.awt.Font("Arial", 1, 12));
incidenceRepCheck.setText("INCIDENT REPORT");
ActivityReport.add(incidenceRepCheck);
incidenceRepCheck.setBounds(130, 70, 130, 20);informationCheck.setBackground(new java.awt.Color(255, 255, 255));
informationCheck.setFont(new java.awt.Font("Arial", 1, 12));
informationCheck.setText(" INFORMATION");
ActivityReport.add(informationCheck);
informationCheck.setBounds(260, 70, 110, 20);followUpRepCheck.setBackground(new java.awt.Color(255, 255, 255));
followUpRepCheck.setFont(new java.awt.Font("Arial", 1, 12));
followUpRepCheck.setText("FOLLOW UP REPORT");
ActivityReport.add(followUpRepCheck);
followUpRepCheck.setBounds(370, 70, 145, 20);clientTextPane.setText("Client Name : Henry Tison");
ActivityReport.add(clientTextPane);
clientTextPane.setBounds(80, 100, 470, 20);// incidentTextArea contains some dynamic data comes from DB
incidentTextAreaScrollPane.setViewportView(incidentTextArea);ActivityReport.add(incidentTextAreaScrollPane);
incidentTextAreaScrollPane.setBounds(20, 480, 620, 110);//Initialize PrintViewActivity class to set AbstractTableModel & dynamic data display
//Create and set up the content pane.
/* printContentPane = new PrintViewActivity();
printContentPane.setOpaque(true); //content panes must be opaque
printActivityReportPanel.add(printContentPane); 
printContentPane.setBounds(20, 130, 620, 230);
*/
getContentPane().add(ActivityReport, java.awt.BorderLayout.CENTER);}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new PrintActivityReport(new javax.swing.JFrame(), true).setVisible(true);
}
});
}private void printActionPerformed(java.awt.event.ActionEvent event) 
{
printButton.setVisible(false);
PrinterJob pj=PrinterJob.getPrinterJob();
pj.setPrintable(PrintActivityReport.this);
pj.printDialog();try{
pj.print();
}
catch (Exception PrintException) {}printButton.setVisible(true);this.setVisible(false);
this.dispose(); 
}
public int print(Graphics g, PageFormat pageFormat,int pageIndex) throws PrinterException 
{
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.black);
int fontHeight=g2.getFontMetrics().getHeight();
int fontDesent=g2.getFontMetrics().getDescent();//leave room for page number
double pageHeight = pageFormat.getImageableHeight()-fontHeight;
double pageWidth = pageFormat.getImageableWidth();return Printable.PAGE_EXISTS;
}}