Provides meta-data for functions. This is basically an extension to the classical bean-info class, with some additional documentations and properties, but without the setter methods (so this class is immutable) and without the event-handler support (as functions cannot support event-handlers).
The ExpressionMetaData makes the assumption, that the expression itself is a bean and that every property descriptor that is retrieved here can also be retrieved using the standard bean-methods using a plain BeanInfo object.
@author Thomas Morgner