Chapter 5 Building Dynamic Diagrams
A decision specifies which alternate path has to be taken when several transition paths are possible. Its symbol is a diamond shape:
A decision can be created in the following diagrams:
A decision can have one or more input transitions and one or more output transitions, each labeled with a distinct guard condition. The process of a decision is based on some defined expressions that direct the control flow towards the valid transition by dynamically evaluating guard conditions.
A guard condition is a condition that must be satisfied for an associated transition to execute some action. Across all these transitions, guard conditions should not overlap to avoid ambiguity but they should cover all possibilities to avoid process freeze.
A decision allows you to create complex flows like:
Handling symbols in the diagram
It is not possible to attach two transitions of opposite directions to the same corner on a decision symbol.
When working with a decision, you can choose to use a conditional branch or a merge. They describe two different situations:
| Copyright (C) 2006. Sybase Inc. All rights reserved. |
| |