Java SE (Java Platform, Standard Edition)

Hi - I am new to Java programming and have been doing the Diana Nourie 'Building the Application' introduction on this site to build the Divelog app. I keep getting the 'Cannot Find Symbol' error. Every forum/google search I have looked at points to a classpath error or a spelling error in the code. My classpath is set correctly as I followed the troubleshooting remedy provided in the 'Application Objects, Classes,Constructors and Methods.pdf.' (http://java.sun.com/developer/onlineTraining/new2java/divelog/) Has anyone out there done this tute and had the same error - if so how did you solve it??

Error is
DiveLog.java:43 cannot find symbol
symbol : class Welcome
location: class divelog.DiveLog
new Welcome<>,

I have six of these errors relating to different classes for tabbedpane.addTab within the following code

package divelog;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class DiveLog
{ //Opens DiveLog class
private JTabbedPane tabbedPane;
private JFrame dlframe;
public DiveLog()
{ //Opens DiveLog constructor
//Create a frame object to add the application
//GUI components to.
dlframe = new JFrame("A Java(TM) Technology Dive Log");
// Closes from title bar
//and from menu
dlframe.addWindowListener(new WindowAdapter()
{ // Opens addWindowListener method
public void windowClosing(WindowEvent e)
{ // Opens windowClosing method
System.exit(0);
} // Closes windowClosing method
}); // Closes addWindowListener method
// Tabbed pane with panels for Jcomponents
tabbedPane = new JTabbedPane(SwingConstants.LEFT);
tabbedPane.setBackground(Color.blue);
tabbedPane.setForeground(Color.white);
// Calls a method that adds individual tabs to the
//tabbedpane object.
populateTabbedPane();
//Calls the method that builds the menu
buildMenu();
dlframe.getContentPane().add(tabbedPane);
dlframe.pack();
dlframe.setSize(765, 690);
dlframe.setBackground(Color.white);
dlframe.setVisible(true);
} // Ends class constructor
private void populateTabbedPane()
{ // Opens populateTabbedPane method definition
// Create tabs with titles
tabbedPane.addTab("Welcome",
null,
new Welcome(),
"Welcome to the Dive Log");
tabbedPane.addTab("Diver Data",
null,
new Diver(),
"Click here to enter diver data");
tabbedPane.addTab("Log Dives",
null,
new Dives(),
"Click here to enter dives");
tabbedPane.addTab("Statistics",
null,
new Statistics(),
"Click here to calculate dive statistics");
tabbedPane.addTab("Favorite Web Site",
null,
new WebSite(),
"Click here to see a web site");
tabbedPane.addTab("Resources",
null,
new Resources(),
"Click here to see a list of resources");
} //Ends populateTabbedPane method
private void buildMenu()
{ // Opens buildMenu method definition
JMenuBar mb = new JMenuBar();
JMenu menu = new JMenu("File");
JMenuItem item = new JMenuItem("Exit");
//Closes the application from the Exit
//menu item.
item.addActionListener(new ActionListener()
{ // Opens addActionListener method
public void actionPerformed(ActionEvent e)
{ // Opens actionPerformed method
System.exit(0);
} // Closes actionPerformed method
}); // Closes addActionListener method
menu.add(item);
mb.add(menu);
dlframe.setJMenuBar(mb);
}// Closes buildMenu method
// main method and entry point for app
public static void main(String[] args)
{ // Opens main method
DiveLog dl = new DiveLog();
} // Closes main method
} //Ends class DiveLog

If anyone could help me out that would be great