Problem adding a table to scrollpane

Question

Hi:
I have created a JTable that I want to be in a scrollpane. When I tried to add this JTable to a scrollpane I get a null pointer error at execution time. But when I add this table directly to the frame I get no error at execution time.
Here is my code:
import java.awt.*;
import java.awt.event .*;
import javax.swing.*;
import java.util.*;
import javax.swing.event.*;
import java.io.*;
import javax.swing.table.*;
import javax.swing.BorderFactory;
import javax.swing.border.Border;
import java.net.*;
import java.util.regex.*;
// METHODS
// =======
// private String returnSelectedString( int col ))
public class DialogFrame extends JFrame
{     //===================
//MEMBER VARIABLES
//===================
public JLabel topClassifiedLabel, bottomClassifiedLabel,printerCountLabel,defaultPrinterLabel ;
public JPanel panelForLabel,topClassificationPanel , bottomClassificationPanel, SecBotPanel, ClassificationPanel,Classification_botPanel,firstTopPanel, titlePanel,titlePanel2,displayPanel,labelPanel,buttonPanel;
public DefaultListModel listModel;
public final String screenTitle = "Printer Configuration "
+ " CSS - 105";
public JLabel localDisplay = new JLabel("Local: Printer directly connected to this computer");
public JLabel remoteDisplay = new JLabel("Remote: Printer connected to another computer");
public JLabel networkDisplay = new JLabel("Network: Printer connected to the LAN");
public char hotKeys[] = { 'A', 'D', 'Q','T','R','I','Q','H' };
public JPanel ConnectTypePanel = null, printCountPanel;
public JScrollPane tabScrollPane;
public JLabel l1,l2,l3,l4,l5,l6,l7,l8,l9,l10,l11,l12,TitleLabel;
public JButton addPrinterButton,setDefaultButton,restartPrintSystemButton, deletePrinterButton, displayQueueButton,
ToggleBannerButton, RestartPrintSystemButton, InstallOpenPrintButton, QuitButton, continueButton,CancelButton,HelpButton;
public Vector columnNames;
public String line2 = "";
public addPrinterDialog aPDialog;
public printQueueDialog dQDialog;
public String nextElement,name,Type,Interface,Description,Status,Queue,BannerPage;
public JRadioButton networkButton, localButton, remoteButton;
public JLabel nameLabel, descriptionLabel, modelLabel,ClassificationLabel,ClassificationLabel_bot,setL,defaultL;
public JTextField nameTextField, descriptionTextField, modelTextField;
private int printerCount = 0;
static DefaultTableModel model;
public JTable table;
//=======================//
//**Constructor
//=========================//
public DialogFrame()
createTable();
public void createTable()
defaultPrinterLabel = new JLabel();
printerCountLabel = new JLabel();
//COLUMN FOR TABLE
columnNames = new Vector();
columnNames.add("Name");
columnNames.add("Type");
columnNames.add("Interface");
columnNames.add("Description");
columnNames.add("Status");
columnNames.add("Queue");
columnNames.add("BannerPage");
Vector tableRow = new Vector();
//tableRow = executeScript("perl garb.pl");
// tableRow = executeScript("perl c:\\textx.pl");
model = new DefaultTableModel( tableRow, columnNames ){
public boolean isCellEditable(int row,int col) {
return false;
public Dimension getPreferredScrollableViewportSize() {
return getPreferredSize();
table = new JTable(model);
JTableHeader header = table.getTableHeader();
TableColumnModel colmod = table.getColumnModel();
for (int i=0; i < table.getColumnCount(); i++)
DefaultTableCellRenderer renderer = new DefaultTableCellRenderer();
renderer.setHorizontalAlignment(SwingConstants.CENTER);
colmod.getColumn(i).setCellRenderer(renderer);
table.setPreferredScrollableViewportSize(new Dimension(500, 70));
table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
table.setShowGrid( false );
table.getTableHeader().setReorderingAllowed( false );
table.setIntercellSpacing(new Dimension(0,0) );
table.addMouseListener( new MouseAdapter () {
public void mouseClicked( MouseEvent e) {
if ((e.getModifiers() & InputEvent.BUTTON1_MASK) !=0)
printSelectCell(table);
this.setSize(900,900);
//========================================//
// Technique for centering a frame on the screen
//===========================================//
Dimension frameSize = this.getSize();
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
this.setLocation((screenSize.width - frameSize.width)/2,
(screenSize.height - frameSize.height)/2);
setResizable(false);
// CREATE A FEW PANELS
firstTopPanel = new JPanel();
BoxLayout box = new BoxLayout(firstTopPanel, BoxLayout.Y_AXIS);
firstTopPanel.setLayout(box);
topClassificationPanel = new JPanel();
topClassificationPanel.setBackground(new Color(45,145,71));
bottomClassificationPanel = new JPanel();
bottomClassificationPanel.setBackground(new Color(45,145,71));
SecBotPanel = new JPanel();
SecBotPanel.setLayout(new BorderLayout());
buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(1,8));
buttonPanel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 0));
buttonPanel.setBackground(new Color(170,187,119));
panelForLabel = new JPanel();
// panelForLabel.setBackground( Color.white );
//Border etchedBorder = BorderFactory.createEtchedBorder();
printerCountLabel.setHorizontalAlignment(SwingConstants.LEFT);
printerCountLabel.setPreferredSize(new Dimension(700, 20));
//printerCountLabel.setBorder(etchedBorder);
printerCountLabel.setForeground(Color.black);
defaultPrinterLabel.setHorizontalAlignment(SwingConstants.RIGHT);
defaultPrinterLabel.setText("Default Printer: " + name);
defaultPrinterLabel.setForeground(Color.black);
panelForLabel.add(printerCountLabel);
panelForLabel.add(defaultPrinterLabel);
titlePanel = new JPanel( );
titlePanel.setBackground( Color.white );
ConnectTypePanel = new JPanel();
ConnectTypePanel.setBackground(new Color(219,223,224));
ConnectTypePanel.setLayout( new GridLayout(3,1) );
//CREATE A FEW LABELS
topClassifiedLabel = new JLabel("UNCLASSIFIED", SwingConstants.CENTER );
topClassifiedLabel.setForeground(Color.white);
bottomClassifiedLabel = new JLabel("UNCLASSIFIED", SwingConstants.CENTER );
bottomClassifiedLabel.setForeground(Color.white);
TitleLabel = new JLabel( screenTitle, SwingConstants.CENTER );
//ADD LABELS TO PANELS
topClassificationPanel.add( topClassifiedLabel );
bottomClassificationPanel.add( bottomClassifiedLabel );
titlePanel.add( TitleLabel, BorderLayout.CENTER );
ConnectTypePanel.add(localDisplay );
ConnectTypePanel.add(remoteDisplay );
ConnectTypePanel.add(networkDisplay );
//Create the scrollpane and add the table to it.
tabScrollPane = new JScrollPane(table);
JPanel ps = new JPanel();
ps.add(tabScrollPane);
getContentPane().setLayout(
new BoxLayout( getContentPane(), BoxLayout.Y_AXIS ) );
getContentPane().add(firstTopPanel);
getContentPane().add(panelForLabel);
getContentPane().add(header);
getContentPane().add(ps);//contain table
getContentPane().add(SecBotPanel);
WindowListener w = new WindowAdapter() {
public void windowClosing(WindowEvent e) {
DialogFrame.this.dispose();
System.exit(0);
this.addWindowListener(w);
//==================================//
// AddPrinterButton
//==================================//
addPrinterButton = new JButton();
addPrinterButton.setLayout(new GridLayout(2, 1));
l1 = new JLabel("Add", JLabel.CENTER);
l1.setForeground(Color.black);
l2 = new JLabel("Printer", JLabel.CENTER);
l2.setForeground(Color.black);
addPrinterButton.add(l1);
addPrinterButton.add(l2);
addPrinterButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event)
//(aPDialog == null) // first time
aPDialog = new addPrinterDialog(DialogFrame.this);
aPDialog.setLocationRelativeTo(null);
aPDialog.pack();
aPDialog.show(); // pop up dialog
//======================================
// DeletePrinterButton
//=====================================
deletePrinterButton = new JButton();
deletePrinterButton.setLayout(new GridLayout(2, 1));
l1 = new JLabel("Delete", JLabel.CENTER);
l1.setForeground(Color.black);
l2 = new JLabel("Printer", JLabel.CENTER);
l2.setForeground(Color.black);
deletePrinterButton.add(l1);
deletePrinterButton.add(l2);
deletePrinterButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event)
int sr = table.getSelectedRow();
if (sr == -1)
JOptionPane.showMessageDialog(null, "You have not selected a printer for this operation","NOSELECT",JOptionPane.INFORMATION_MESSAGE);
else
name = returnSelectedString(0);
int ans = JOptionPane.showConfirmDialog(null,"Are you sure you want to delete printer " + name + "?","Delete",JOptionPane.YES_NO_OPTION);
switch(ans) {
case JOptionPane.NO_OPTION:
return;
case JOptionPane.YES_OPTION:
// String machineName = returnSelectedString(0);
int rowNumber = table.getSelectedRow();
model.removeRow(rowNumber);
//TiCutil.exe("/usr/lib/lpadmin -x " + machineName);
decreasePrinterCount();
JOptionPane.showMessageDialog(null, "Printer " + name + " have been successfully deleted","SUCCEED",JOptionPane.INFORMATION_MESSAGE);
return;
//==============================//
//DisplayQueuePrinter //
//================================//
displayQueueButton = new JButton();
displayQueueButton.setLayout(new GridLayout(2, 1));
l5 = new JLabel("Display", JLabel.CENTER);
l5.setForeground(Color.black);
l6 = new JLabel("Queue", JLabel.CENTER);
l6.setForeground(Color.black);
displayQueueButton.add(l5);
displayQueueButton.add(l6);
displayQueueButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event)
Vector tab = new Vector();
int sr = table.getSelectedRow();
if (sr == -1)
JOptionPane.showMessageDialog(null, "You have not selected a printer for this" +
"operation","NOSELECT",JOptionPane.INFORMATION_MESSAGE);
else
name = returnSelectedString(0);
//PASS TABLE HERE
/*tab = executeScript("lpstat -o " + name + " | sed \'s/ on$//\'");
System.out.println("lpstat -o " + name + " | sed \'s/ on$//\'");
dQDialog = new printQueueDialog(DialogFrame.this, name, tab);
dQDialog.setLocationRelativeTo(null);
dQDialog.pack();
dQDialog.show(); // pop up dialog */
//===================================
// SetDefaultButton
//================================//
setDefaultButton = new JButton();
setDefaultButton.setLayout(new GridLayout(2, 1));
setL = new JLabel("Set", JLabel.CENTER);
setL.setForeground(Color.black);
defaultL = new JLabel("Default", JLabel.CENTER);
defaultL.setForeground(Color.black);
setDefaultButton.add(setL);
setDefaultButton.add(defaultL);
setDefaultButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event)
int sr = table.getSelectedRow();
if (sr == -1)
JOptionPane.showMessageDialog(null, "You have not selected a printer for this operation","NOSELECT",JOptionPane.INFORMATION_MESSAGE);
else
name = returnSelectedString(0);
JOptionPane.showMessageDialog(null, "printer " + name + " is now the default.","Succeed",JOptionPane.INFORMATION_MESSAGE);
defaultPrinterLabel.setText("Default Printer: " + name);
//==============================//
// ToggleBannerButton
//==============================//
ToggleBannerButton = new JButton();
ToggleBannerButton.setLayout(new GridLayout(2, 1));
l7 = new JLabel("Toggle", JLabel.CENTER);
l7.setForeground(Color.black);
l8 = new JLabel("Banner", JLabel.CENTER);
l8.setForeground(Color.black);
ToggleBannerButton.add(l7);
ToggleBannerButton.add(l8);
ToggleBannerButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event)
int sr = table.getSelectedRow();
System.out.println("sr :" + sr);
if (sr == -1)
JOptionPane.showMessageDialog(null, "You have not selected a printer for this operation","NOSELECT",JOptionPane.INFORMATION_MESSAGE);
else
String banner = returnSelectedString(6);
name = returnSelectedString(0);
String machineName = returnSelectedString(0);
Type = returnSelectedString(1);
if ( !(Type.equals("Remote")) )
if( banner.equals("Yes") )
JOptionPane.showMessageDialog(null,"Banner page will NOT be printed for printer "+ name ,"Succeed",JOptionPane.INFORMATION_MESSAGE);
//TiCutil.exe("sed -e 's/^BANNER=\"yes\"/BANNER=\"\"/' /etc/lp/interfaces/" + machineName + " > /tmp/delete.txt" );
//TiCutil.exe("mv /tmp/delete.txt /etc/lp/interfaces/" + machineName);
table.setValueAt("No",sr,6);
DefaultTableModel model = (DefaultTableModel)table.getModel();
model.fireTableCellUpdated(sr,6);
table.requestFocus();
else
JOptionPane.showMessageDialog(null,"Banner page WILL be printed for printer "+ name ,"Succeed",JOptionPane.INFORMATION_MESSAGE);
//TiCutil.exe("sed -e 's/^BANNER=\"\"/BANNER=\"yes\"/' /etc/lp/interfaces/" + machineName + " > /tmp/delete.txt");
//TiCutil.exe("mv /tmp/delete.txt /etc/lp/interfaces/" + machineName);
table.setValueAt("Yes",sr,6);
DefaultTableModel model = (DefaultTableModel)table.getModel();
model.fireTableCellUpdated(sr,6);
table.requestFocus();
else
JOptionPane.showMessageDialog(null,"Operation failed system respond \n" + "was:\n" + "cannot toggle the banner page for a\n" + "REMOTE printer." ,"OPFAIL",JOptionPane.INFORMATION_MESSAGE);
//==================================//
// RestartPrintSystemButton
//==================================//
restartPrintSystemButton = new JButton();
restartPrintSystemButton.setLayout(new GridLayout(2, 1));
l3 = new JLabel("Restart Print", JLabel.CENTER);
l3.setForeground(Color.black);
l4 = new JLabel("System", JLabel.CENTER);
l4.setForeground(Color.black);
restartPrintSystemButton.add(l3);
restartPrintSystemButton.add(l4);
restartPrintSystemButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event)
//==============================
// InstallOpenPrint
//================================
InstallOpenPrintButton = new JButton();
InstallOpenPrintButton.setLayout(new GridLayout(2, 1));
l11 = new JLabel("Install Open", JLabel.CENTER);
l11.setForeground(Color.black);
l12 = new JLabel("Print", JLabel.CENTER);
l12.setForeground(Color.black);
InstallOpenPrintButton.add(l11);
InstallOpenPrintButton.add(l12);
InstallOpenPrintButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event)
int ans = JOptionPane.showConfirmDialog(null,"Are you sure you want to install OPENPrint?","Delete",JOptionPane.YES_NO_OPTION);
switch(ans) {
case JOptionPane.NO_OPTION:
return;
case JOptionPane.YES_OPTION:
int cd,opinstall,banner_var,pwd;
opinstall = runIt("open_print.ksh");
banner_var = runIt("banner_var.ksh");
System.out.println("opinstall: " + opinstall );
System.out.println("banner_var: " + banner_var);
if ( opinstall == 0 && banner_var == 0)
JOptionPane.showMessageDialog(null, "OPENprint successfully added"
,"SUCCEED",JOptionPane.INFORMATION_MESSAGE);
return;
//==========================
//QuitButton
//============================
QuitButton = new JButton("Quit");
QuitButton.addActionListener (new ActionListener ()
{ public void actionPerformed (ActionEvent e){
System.exit (0); }
HelpButton = new JButton("Help");
//ADD BUTTONS TO PANEL
buttonPanel.add( addPrinterButton );
buttonPanel.add( deletePrinterButton );
buttonPanel.add( displayQueueButton );
buttonPanel.add( setDefaultButton);
buttonPanel.add( ToggleBannerButton );
buttonPanel.add( restartPrintSystemButton );
buttonPanel.add( InstallOpenPrintButton );
buttonPanel.add( QuitButton );
//buttonPanel.add( HelpButton );
//END OF BUTTONS CREATION
//ADD PANEL ON TO PANEL
SecBotPanel.add(ConnectTypePanel, BorderLayout.CENTER);
SecBotPanel.add(bottomClassificationPanel, BorderLayout.SOUTH);
firstTopPanel.add(topClassificationPanel);
firstTopPanel.add(titlePanel);
firstTopPanel.add(buttonPanel);
//===========================================================
// METHODS
//==========================================================
public int runIt(String targetCode)
int result = -1;
try{
Runtime rt = Runtime.getRuntime();
Process p = rt.exec( targetCode );
// Thread.sleep(20000);
p.waitFor();
result = p.exitValue();
catch( IOException ioe )
ioe.printStackTrace();
catch( InterruptedException ie )
ie.printStackTrace();
return result;
//====================================================
public void increasePrinterCount()
printerCount++;
printerCountLabel.setText("Printer: " + printerCount);
//===========================================================
public void decreasePrinterCount()
printerCount--;
printerCountLabel.setText("Printer: " + printerCount);
private String returnSelectedString( int col )
int row = table.getSelectedRow();
String word;
//javax.swing.table.TableModel model = table.getModel();
word =(String)model.getValueAt(row, col);
return word; //return string
//==============================================================================
private Vector executeScript(String str)
Vector tableOfVectors = new Vector();
try{          
String line;
Process ls_proc = Runtime.getRuntime().exec(str);
//get its output (your input) stream
BufferedReader in = new BufferedReader( new InputStreamReader( ls_proc.getInputStream() ));
//readLine reads in one line of text
int k = 1, i = 0;
//LOOK FOR THE "|"
Pattern p = Pattern.compile(" ");
while (( line = in.readLine()) != null)
Vector data = new Vector();
Matcher m = p.matcher(line);
if(m.find() == true)//find " "
line = line.replaceAll(" {2,}?", "|");
//creates a new vector for each new line read in
StringTokenizer t = new StringTokenizer(line,"|");
while ( t.hasMoreTokens() )
try
nextElement = t.nextToken().trim();
//add a string to a vector
data.add(nextElement.trim());
catch(java.util.NoSuchElementException nsx)
System.out.println(nsx);
tableOfVectors.add(data);
//COUNT THE NUMBER OF PRINTER
printerCount = k;
printerCountLabel.setText("Printer: " + printerCount);
k++;
}//END OF WHILE
in.close();
}//END OF TRY
catch (IOException e1) {
System.err.println(e1);
System.exit(1);
return tableOfVectors;
//==========================================================================================================
private String getDefaultPrinter(String str)
String groupStr = null;
try{          
String lin;
Process ls_proc = Runtime.getRuntime().exec(str);
BufferedReader in = new BufferedReader( new InputStreamReader( ls_proc.getInputStream() ));
Pattern p2 = Pattern.compile("system default destination: (\\S+)");
while (( lin = in.readLine()) != null)
Matcher m2 = p2.matcher(lin);
m2.reset(lin);
if (m2.find() == true )
groupStr = m2.group(1);
in.close();
catch (IOException e1) {
System.err.println(e1);
System.exit(1);
return groupStr;
//================================================================================
public synchronized void clearTable()
int numrows = model.getRowCount();
for ( int i = numrows -1 ; i >= 0 ; i--)
model.removeRow(i);
//=======================================================================================================
private void printSelectCell(JTable table )
int numCols = table.getColumnCount();
int row = table.getSelectedRow();
System.out.println(row);
javax.swing.table.TableModel model = table.getModel();
for(int j=0;j < numCols; j++)
System.out.println(" " + model.getValueAt(row,j));
System.out.println();
System.out.println("-----------------------------------------------");
//CREATE ADD PRINTER DIALOG
class addPrinterDialog extends JDialog
public addPrinterDialog(JFrame owner)
super(owner, "ap1", true);
final ButtonGroup rbg = new ButtonGroup();
JPane

Answer 1

Ok  I have the table  on the page  I created a css with a background image called .search  How to I link that to the table so It shows the image
I am only used to doing certain css items   Never didi this before
THXS STeve