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
/*******************************************************************************
 * Copyright (c) 2000, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
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package org.eclipse.jface.wizard;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.jface.dialogs.ControlEnableState;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.dialogs.IMessageProvider;
import org.eclipse.jface.dialogs.IPageChangeProvider;
import org.eclipse.jface.dialogs.IPageChangedListener;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.dialogs.PageChangedEvent;
import org.eclipse.jface.dialogs.TitleAreaDialog;
import org.eclipse.jface.operation.IRunnableWithProgress;
import org.eclipse.jface.operation.ModalContext;