UML activity Diagram Activities diagram

Preface

In the summary of the UML state diagram, the activity diagram and the state diagram are closely related. It also has a lot in common with flowcharts.

definition

An activity diagram is a special form of a state diagram. All or most of these states are active, and all or most of the transfers are triggered immediately when the activity in the source state is complete.

Use

The workflow activity diagram is used to study the sequencing of tasks or activities to be performed when implementing a business goal.

1. Describe the work or action done during the execution of an operation.

2. Describe the work inside the object.

3. Shows how to perform a set of related actions, and how these actions affect the surrounding objects.

4. Describe the execution of the use case.

5, processing multi-threaded applications.

not suitable for use with activity diagrams

1, display the cooperation between objects.

2. Display the operation of the object during its life cycle.

Behavioral Model

System modeling needs to be described from two aspects of the structure and behavior of the system, wherein the behavior of the system is described by state diagram, activity diagram, sequence diagram and collaboration diagram.

Relationship with Flowchart

Flowcharts are often used to build algorithmic models, using flowcharts to represent an algorithm's execution sequence, process, decision Point, Branch, and loop.

The activity diagram is similar to a flowchart, except that it supports parallel activities.

Disadvantages

It is difficult to clear the relationship between the description action and the object, no interaction graph directly.

Basic ElementsActive state (ellipse representation)Transferjudgment--a special activity that represents the decision-making of judgment. Guarantee conditions-the transfer occurs only if the guarantee condition is true. synchronization Bars-a special activity that represents the synchronization between activities. starting point and end point-there is only one starting point, and there are multiple endpoints. Swimlane--used to group activities on the activity diagram, and the user describes the relationships between objects. Computer room charge system activity Chartyou are welcome to make valuable suggestions.

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

UML activity Diagram Activities diagram