What is the difference between sequence diagram and communication diagram?

uml sequence-diagram communication-diagram
Quang Huynh picture Quang Huynh · Apr 10, 2012 · Viewed 24.8k times · Source

Could anyone explain me what is the difference between sequence diagram and communication diagram?

Answer

Ray Toal picture Ray Toal · Apr 10, 2012

Both diagrams give the same information, but the sequence diagram emphasizes time in its layout and the communication diagram emphasizes the objects that are communicating in its layout.

Time is implicit in sequence diagrams (it is inferred by vertical position), while it is given explicitly in communication diagrams (via numbers).

To quote Scott Ambler

The main difference between communication diagrams and sequence diagrams is that sequence diagrams are good at showing sequential logic but not that good at giving you a “big picture view” whereas communication diagrams are the exact opposite.

Related questions

How to show "if" condition on a sequence diagram?

I was wondering, how can one represent "if" statement on a sequence diagram? if (somethingShouldBeDone) { // Do it } else { // Do something else } Can it be represented at all? The thing is ... in my code, fair amount of conditions are checked to …

Read More
How to represent a call being made in a loop in a sequence diagram?

I'm creating a sequence diagram, and one of the classes is being observed by another class. The observed class is calling update in the observer every 5 seconds in a loop. I need to show this in the sequence diagram. Is …

Read More
How to Generate a Sequence Diagram from Java Source Code

I have a question about generating sequence diagram from Java source code. When I googled I saw someone told to use visual paradigm (VP), but it does not generate sequence diagram for me. Some steps in my VP are different …

Read More