Adds all of the elements in the specified set to this attribute. The outcome is the same as if the
operation had been applied to this attribute set successively with each element from the specified set. If none of the categories in the specified set are the same as any categories in this attribute set, the
operation effectively modifies this attribute set so that its value is the union
of the two sets.
The behavior of the
addAll() operation is unspecified if the specified set is modified while the operation is in progress.
addAll() operation throws an exception, the effect on this attribute set's state is implementation dependent; elements from the specified set before the point of the exception may or may not have been added to this attribute set.