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
/* (non-Javadoc)
             * @see org.eclipse.jface.wizard.ProgressMonitorPart#subTask(java.lang.String)
             */
            public void subTask(String name) {
                super.subTask(name);
                
                if (currentTask == null)
                    currentTask = name;
            }
        };
    }
    /**
     * Creates the container that holds all pages.
     * @param parent
     * @return Composite
     */
    private Composite createPageContainer(Composite parent) {
        Composite result = new Composite(parent, SWT.NULL);
        result.setLayout(pageContainerLayout);
        return result;
    }
    /**
     * Allow the wizard's pages to pre-create their page controls.
     * This allows the wizard dialog to open to the correct size.
     */
    private void createPageControls() {
        
        
        wizard.createPageControls(pageContainer);