this class manages collaboration diagram definition
Declaration :
Directly inherited by : UmlCollaborationDiagramDefinition
Artifact : UmlBaseCollaborationDiagramDefinition
| Operation instances | 
return the instances present in the diagram
Declaration :
| Operation messages | 
return the messages present in the diagram,
 ordonned following their rank
Declaration :
| Relation _instances (<directional composition>) | 
Declaration :
Stereotype: vector
| Relation _messages (<directional composition>) | 
Declaration :
Stereotype: vector
| Operation read_ | 
internal, don't call it
Declaration :
| Operation ~UmlBaseCollaborationDiagramDefinition | 
  to avoid compiler warning, don't call it
Declaration :
| Extra Class Member friend | 
Definition :
friend class UmlBaseCollaborationDiagram;