string
getDefaultGroup()
Returns the name of the default group for this class. For each class, the group "Default" is an alias for the group "", where is the non-namespaced name of the class. All constraints implicitly or explicitly assigned to group "Default" belong to both of these groups, unless the class defines a group sequence. If a class defines a group sequence, validating the class in "Default" will validate the group sequence. The constraints assigned to "Default" can