HelpSet.findHelpSet() returns null, and trapping ID errors

Question

I was having a problem initializing JavaHelp. HelpSet.findHelpSet() was returning null. I searched the forum, and found it was a common problem, but the answers were unhelpful. The answers pointed to a problem with CLASSPATH, but offered little in the way of advice for a newbie like myself on how to deal with it.
A second issue concerns HelpBroker.enableHelpOnButton(). If you feed it a bogus ID, it throws an exception, and there's no way to trap it and fail gracefully. JHUG doesn't provide much in the way of alternatives.
Now, having done a bit of research and testing, I'm willing to share a cookbook formula for what worked for me.
I'm working in a project directory that contains MyApp.jar and the Help subdirectory, including Help/Help.hs. My first step is to copy jh.jar to the project directory.
Next, in the manifest file used to generate MyApp.jar, I add the line:
    Class-Path: jh.jar Help/I'm working with Eclipse, so in Eclipse, I use Project - Properties - Java Build Path - Libraries to add JAR file jh.jar, and Class Folder Tony/Help
I define the following convenience class:
public class HelpAction extends AbstractAction
    private static HelpBroker helpBroker = null;
    private String label = null;
    public HelpAction( String name, String label )
        super( name );
        this.label = label;
    public void actionPerformed( ActionEvent event )
        displayHelp( label );
    public static boolean displayHelp( String label )
        if ( helpBroker == null )
            Utils.reportError( "Help package not initialized!" );
            return false;
        try
            helpBroker.setCurrentID( label );
            helpBroker.setDisplayed( true );
            return true;
        catch ( Exception e )
            Utils.reportError( e, "Help for " + label + " not found" );
            return false;
    public static boolean initialize( String hsName )
        URL hsURL = HelpSet.findHelpSet( null, hsName );
        if ( hsURL == null )
            Utils.reportError( "Can't find helpset " + hsName );
            return false;
        try
            HelpSet helpSet = new HelpSet( null, hsURL );
            helpBroker = helpSet.createHelpBroker();
        catch ( HelpSetException e )
            Utils.reportError( e, "Can't open helpset " + hsName );
            return false;
        return true;
}If you use this class in your own code, you'll want to replace Utils.reportError() with something of your own devising.
Finally, in my GUI class, I use the following:
    JPanel panel = ...
    JMenu menu = ...
    JToolbar toolbar = ...
    HelpAction.initialize( "Help.hs" )
    Action gsAction = new HelpAction( "Getting Started Guide", "gs.top" );
    menu.add( gsAction );
    JButton helpButton = new HelpAction( "Help", "man.top" );
    toolbar.add( helpButton );
    InputMap imap = panel.getInputMap( JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT );
    imap.put( KeyStroke.getKeyStroke( "F1" ), "F1help" );
    ActionMap amap = panel.getActionMap();
    amap.put( "F1help", new HelpAction( null, "man.top" ) );

Answer 1

Sorry, the sixth-from-last line of my example should read,
    JButton helpButton = new JButton( new HelpAction( "Help", "man.top" ) );