/*
 * STRUCT: SE_Requirement
 *
 *   Describes a relationship between two classes.  One class, the "from"
 *   class or "current" class, is taken from a context outside of this
 *   structure, while the "to" class is identified in this structure. The
 *   relationship from the "from" class to the "to" class is defined by this
 *   structure.
 *
 *   The relationship being described may be an association, aggregation,
 *   or component relationship.  Each class has a list of its association
 *   requirements, a list of its aggregation requirements, and a list of
 *   its component requirements. These lists are accessed via
 *   SE_AssociationsList(), SE_AggregatesList(), and SE_ComponentsList()
 *   (see). The SE_Requirement struct defined here is used as an
 *   entry in those lists.
 *
 *  Another way to describe lower_limit and upper_limit:
 *
 *     For fixed size arrays,
 *           multiplicity == SE_MLTPCTY_EXACTLY_N
 *           lower_limit  == upper_limit == (value of N)
 *
 *     For bounded arrays (at least N, at most M),
 *           multiplicity == SE_MLTPCTY_BOUNDED_ARRAY
 *           lower_limit  == (N, the lower bound value)
 *           upper_limit  == (M, the upper bound value)
 *
 *     For unbounded arrays (at least N, no upper bound),
 *           multiplicity == SE_MLTPCTY_UNBOUNDED_ARRAY
 *           lower_limit  == (N, lower bound value)
 *           upper_limit  == NO_UPPER_BOUND (-1)
 */

Field Notes

drm_class

The ID of the 'to' class, always meaningful.

multiplicity

The multiplicity of the "to" side of the relationship, always meaningful. It answers the question "How many of the 'to' class objects are required to be related to a 'from' class object?"

ordered

When more than one object of the "to" class is allowed, this ordered flag indicates whether or not the ordering of those "to" objects is important. This ordered flag is meaningful only when the multiplicity allows more than one "to" class object (i.e. - this ordered flag should be SE_FALSE, but should also be ignored and is not meaningful when the multiplicity is SE_MLTPCTY_EXACTLY_ONE or SE_MLTPCTY_ZERO_OR_ONE).

lower_limit

The lower limit for the number of "to" class objects. Only meaningful for multiplicity values of SE_MLTPCTY_EXACTLY_N, SE_MLTPCTY_BOUNDED_ARRAY, and SE_MLTPCTY_UNBOUNDED_ARRAY. The meaning of lower_limit is:

• for SE_MLTPCTY_EXACTLY_N, the lower_limit equals N, requiring exactly N "to" objects
• for SE_MLTPCTY_BOUNDED_ARRAY, the lower_limit is the minimum number of "to" objects required
• for SE_MLTPCTY_UNBOUNDED_ARRAY, the lower_limit is the minimum number of "to" objects required

upper_limit

The upper limit for the number of "to" class objects. Only meaningful for multiplicity values of SE_MLTPCTY_EXACTLY_N, SE_MLTPCTY_BOUNDED_ARRAY, and SE_MLTPCTY_UNBOUNDED_ARRAY. The meaning of upper_limit is:

• for SE_MLTPCTY_EXACTLY_N, the upper_limit equals N, requiring exactly N "to" objects (the value N is stored in both the lower_limit and upper_limit for multiplicity SE_MLTPCTY_EXACTLY_N)
• for SE_MLTPCTY_BOUNDED_ARRAY, the upper_limit is the maximum number of "to" objects required
• for SE_MLTPCTY_UNBOUNDED_ARRAY, there is no upper limit for the number of "to" objects required, so upper_limit is set to the sentinel value SE_NO_UPPER_BOUND

drm_link_class

Set to the link class, if the relationship has one; otherwise, set to SE_CLS_DRM_NULL.

next_ptr

A pointer to the next SE_Requirement struct in this singly-linked list of requirements; NULL if end-of-list.