CL_WD_WEB_ICON 
The static methods of this class provide information about Web Icons.
This method returns collections of Web icons.
This method returns Web icons for a collection or for all collections.
This method returns the relevant URL for a Web Dynpro application.
The URL of a Web icon can depend on the writing direction. Further dependencies of environment information for a Web Dynpro application are possible in future:
This method is not needed in UI elements since the use of alias, ~Icon/HtmlFile, for instance, is sufficient.