The difference between sequence and communication scheme (UML)

Question

What is the difference between sequence diagrams and communication (collaboration) diagrams in UML?

Answer 1

Quoting Wikipedia :

Communication diagrams display most of the same information as sequence diagrams, but due to the way the information is presented, some of them are easier to find on one diagram than others are strong>. Communication diagrams show which elements interact better with each other, but sequence diagrams show the order in which interactions occur more clearly.

In essence, a collaboration diagram emphasizes which objects interact with each other, while sequence diagrams put more emphasis on the actual order. But they are actually equivalent, with the exception of a little more detailed information visible in the sequence diagrams, for example, when and by whom the object was created / destroyed.

Answer 2

The flowchart makes it easy to track interactions as they run from top to bottom, so finding the order of messages is pretty simple. But if you have many interacting objects, the chart becomes difficult to read.

Communication diagrams show which messages are transmitted between objects with a sequence written above the message. For large numbers of objects, this is easier to understand than a sequence diagram, but a message sequence is harder to understand.

Answer 3

In the sequence of life cycles of a sequence, an element exists and is potentially involved in the interaction. In the communication diagram, the life cycle is a separate participant in the interaction.

Answer 4

The sequence and communication diagrams show almost equivalent information, there are strengths and weaknesses:

Sequential Charts:

It is easy to see the ordering of messages from object to object over time.

Communication schemes:

It is easy to see links, role names and traffic flow between a specific configuration of objects.