synchronous

1
types of message flows

• synchronous
• indicates nested flow of control
• used to ensure that state cannot be compromised
  by
• external factors e.g. not interrupted by the
  operating system
• invoking object halts execution while it waits
  for a return
• completion
• invoked object finishes
• asynchronous
• signal from one object to another
• invoking object does not halt execution while it
  waits a return
• callback
• notification of completion from invoked object

2
iteration and conditions
3
print shop
branching and asynchronous messages and deletion
of objects
4
use case place a telephone call
this diagram could be extended to show the two
parties disconnecting
5
Fig. 12.24 UML and the Unified Process Practical
Object-Oriented Analysis and Design. Arlow
Neustadt. Addison-Wesley. 2002
6
showing active
7
multi- threading