Overview

Document object interactions and message flows within a use case or scenario using this Collaboration (Communication) Diagram template. A UML collaboration diagram emphasizes the structural organization of objects and the messages they exchange — complementing sequence diagrams by showing relationships and communication paths spatially rather than temporally.

Key Features

• Object node blocks with class and instance name fields
• Numbered message arrows showing communication sequence between objects
• Bidirectional and unidirectional message connectors
• Relationship links between associated objects
• Comparison zone for viewing collaboration and sequence diagrams side-by-side

How to Use

1. Add object nodes using the Shapes tool — label each with the object name and class (format: objectName : ClassName)
2. Draw association links between objects that communicate using the Connector tool — these represent structural relationships, not flow
3. Add message arrows along the association links — label each with a sequence number and method call using the Text tool (e.g., "1: authenticate()")
4. Use a distinct color for return messages to distinguish calls from responses
5. Place your collaboration diagram next to an equivalent sequence diagram using frames to show the same scenario from both structural and temporal perspectives

Benefits

Collaboration diagrams reveal something sequence diagrams hide: the network of object relationships. When the spatial arrangement of objects reflects the system's architecture, design problems become visible at a glance.