ERROR - Problem assembling the enunciate app. (unknown source position): Accessor of : An interface type cannot be an xml type

Error

Failed to execute goal org.codehaus.enunciate:maven-enunciate-plugin::docs (default) on project : Problem assembling the enunciate app. (unknown source position): Accessor of : An interface type cannot be an xml type. -> [Help 1]

Error Type

Maven Build Enunciate

Possible Cause

One cannot associate Interface type using @XmlElement without the specifying the implementation class.

Sample Code 

@XmlElement
private final CalendarInterface calendar;

Resolution

Specify the implementation class as an argument 

@XmlElement (type=GregorianCalendar.class)
private final CalendarInterface calendar;