Bug 82706 [Wizards] WizardDialog: code inconsistent
As long as WizardDialog.updateTitleBar() is a public method (should it be?) it's not a bad idea to check dialog state in all appropriate places. Now: public void updateTitleBar() { String s = null; if(currentPage != null) s = currentPage.getTitle(); if (s == null) s = ""; //$NON-NLS-1$ setTitle(s); if(currentPage != null) setTitleImage(currentPage.getImage()); updateDescriptionMessage(); updateMessage(); } It accurately checks that currentPage != null, but forgets to do the same before calling of updateDescriptionMessage() method wich works with currentPage without any checking. This can cause NPE (which happened to me :-)).
bundles/org.eclipse.jface/src/org/eclipse/jface/wizard/WizardDialog.java
if (currentPage != null)
            setTitleImage(currentPage.getImage());
        updateDescriptionMessage();
        updateMessage();
    }
    /* (non-Javadoc)
     * Method declared on IWizardContainer.
     */
    public void updateWindowTitle() {
        if (getShell() == null)
            
            return;
        String title = wizard.getWindowTitle();
        if (title == null)
            title = ""; 
        getShell().setText(title);
    }
	/* (non-Javadoc)
	 * @see org.eclipse.jface.dialogs.IPageChangeProvider#getSelectedPage()
	 */
	public Object getSelectedPage() {
		return getCurrentPage();
	}
   /* (non-Javadoc)
    * @see org.eclipse.jface.dialog.IPageChangeProvider#addPageChangedListener()
    */
	public void addPageChangedListener(IPageChangedListener listener) {
		pageChangedListeners.add(listener);
	}
   /* (non-Javadoc)