Bug 21631 JavaUI.createTypeDialog() should provide default message [dialogs]
2.0 Release If you use JavaUI.createTypeDialog() to create a new (single selection) type dialog, and then open the dialog, the open will fail silently. The dialog cannot be succesfully opened unless you send setMessage() to the dialog before you open it. This behaviour should be documented, or, preferably, a default message ("Please select a type/class/interface") should be provided.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/JavaUI.java
* can be safely cast to an <code>ITypeHierarchyViewPart</code>.
	 * </p>
	 *
	 * @see ITypeHierarchyViewPart
	 * @see org.eclipse.ui.IWorkbenchPage#findView(java.lang.String)
	 * @see org.eclipse.ui.IWorkbenchPage#showView(java.lang.String)
	 */ 
	public static final String ID_TYPE_HIERARCHY= 		"org.eclipse.jdt.ui.TypeHierarchy"; 
	/**
	 * The id of the Java Browsing Perspective
	 * (value <code>"org.eclipse.jdt.ui.JavaBrowsingPerspective"</code>).
	 * 
	 * @since 2.0
	 */
	public static String ID_BROWSING_PERSPECTIVE= "org.eclipse.jdt.ui.JavaBrowsingPerspective"; 
	/**
	 * The view part id of the Java Browsing Projects view
	 * (value <code>"org.eclipse.jdt.ui.ProjectsView"</code>).
	 * 
	 * @since 2.0
	 */
	public static String ID_PROJECTS_VIEW= "org.eclipse.jdt.ui.ProjectsView"; 
	/**
	 * The view part id of the Java Browsing Packages view
	 * (value <code>"org.eclipse.jdt.ui.PackagesView"</code>).
	 * 
	 * @since 2.0
	 */
	public static String ID_PACKAGES_VIEW= "org.eclipse.jdt.ui.PackagesView"; 
	/**