Activity Diagram

To be able to generate those diagram, you must have Graphviz software installed on your machine in the default directory c:\Program Files\GraphvizX.XX or /usr/bin/dot.

You can have a look here if you have installed Graphviz somewhere else.

Simple Activity

You can use (*) for the starting point and ending point of the activity diagram.

In some occasion, you may want to use (*top) to force the starting point to be at the top of the diagram.

Use --> for arrows.

@startuml

(*) --> "First Activity"
"First Activity" --> (*)

@enduml

Label on arrows

By default, an arrow starts at the last used activity.

You can put a label on a arrow using brackets [ and ] just after the arrow definition.

@startuml

(*) --> "First Activity"
-->[You can put also labels] "Second Activity"
--> (*)

@enduml

Changing arrow direction

You can use -> for horizontal arrows. It is possible to force arrow's direction using the following syntax:

-down-> (default arrow)
-right-> or ->
-left->
-up->

@startuml

(*) -up-> "First Activity"
-right-> "Second Activity"
--> "Third Activity"
-left-> (*)

@enduml

Branches

You can use if/then/else keywords to define branches.

@startuml
(*) --> "Initialisation"

if "Some Test" then
  -->[true] "Some Activity"
  --> "Another activity"
  -right-> (*)
else
  ->[false] "Something else"
  -->[Ending process] (*)
endif

@enduml

Unfortunalty, you will have to sometimes repeat the same activity in the diagram text:

@startuml
(*)  --> "check input"
If "input is verbose" then
--> [Yes] "turn on verbosity"
--> "run command"
else
--> "run command"
Endif
-->(*)
@enduml

This is a major drawback of the current syntax, and that's why a new syntax proposal is pending, closer to a script language.

More on Branches

By default, a branch is connected to the last defined activity, but it is possible to override this and to define a link with the if keywords.

It is also possible to nest branches.

@startuml

(*) --> if "Some Test" then

  -->[true] "activity 1"
  
  if "" then
    -> "activity 3" as a3
  else
    if "Other test" then
      -left-> "activity 5"
    else
      --> "activity 6"
    endif
  endif
  
else

  ->[false] "activity 2"
  
endif

a3 --> if "last test" then
  --> "activity 7"
else
  -> "activity 8"
endif

@enduml

Synchronization

You can use === code === to display synchronization bars.

@startuml

(*) --> ===B1=== 
--> "Parallel Activity 1"
--> ===B2===

===B1=== --> "Parallel Activity 2"
--> ===B2===

--> (*)

@enduml

Long activity description

When you declare activities, you can span on several lines the description text. You can also add \n in the description.

It is also possible to use few html tags like :



 or <size:nn> to change font size
 or 
<color:#AAAAAA> or <color:colorName>
<img:file.png> to include an image

You can also give a short code to the activity with the as keyword. This code can be used latter in the diagram description.

@startuml
(*) -left-> "this <size:20>activity</size>
	is <b>very</b> <color:red>long2</color>
	and defined on several lines
	that contains many <i>text</i>" as A1

-up-> "Another activity\n on several lines"

A1 --> "Short activity <img:sourceforge.jpg>"
@enduml

Notes

You can add notes on a activity using the command note left, note right, note top or

note
bottom

, just after the description of the activity you want to note.

If you want to put a note on the starting point, define the note at the very beginning of the diagram description.

You can also have a note on several lines, using the end note keywords.

@startuml

(*) --> "Some Activity"
note right: This activity has to be defined
"Some Activity" --> (*)
note left
 This note is on
 several lines
end note

@enduml

Partition

You can define a partition using the partition keyword, and optionally declare a background color for your partition (Using a html color code or name)

When you declare activities, they are automatically put in the last used partition.

You can close the partition definition using the end partition keyword or by using a closing bracket }.

@startuml

partition Conductor {
  (*) --> "Climbs on Platform"
  --> === S1 ===
  --> Bows
}

partition Audience LightSkyBlue {
  === S1 === --> Applauds
}

partition Conductor {
  Bows --> === S2 ===
  --> WavesArmes
  Applauds --> === S2 ===
}

partition Orchestra #CCCCEE {
  WavesArmes --> Introduction
  --> "Play music"
}

@enduml

Title the diagram

The title keywords is used to put a title.

You can use title and end title keywords for a longer title, as in sequence diagrams.

@startuml
title Simple example\nof title 

(*) --> "First activity"
--> (*)
@enduml

Skinparam

You can use the skinparam command to change colors and fonts for the drawing.

You can use this command :

In the diagram definition, like any other commands,
In an included file,
In a configuration file, provided in the command line or the ANT task.

You can define specific color and fonts for stereotyped activities.

@startuml

skinparam backgroundColor #AAFFFF
skinparam activity {
  StartColor red
  BarColor SaddleBrown 
  EndColor Silver
  BackgroundColor Peru
  BackgroundColor<< Begin >> Olive
  BorderColor Peru
  FontName Impact
}

(*) --> "Climbs on Platform" << Begin >>
--> === S1 ===
--> Bows
--> === S2 ===
--> WavesArmes
--> (*)

@enduml

Octagon

You can change the shape of activities to octagon using the skinparam activityShape octagon command.

@startuml
'Default is skinparam activityShape roundBox
skinparam activityShape octagon

(*) --> "First Activity"
"First Activity" --> (*)

@enduml

Complete example

@startuml
'http://click.sourceforge.net/images/activity-diagram-small.png
title Servlet Container

(*) --> "ClickServlet.handleRequest()"
--> "new Page"

if "Page.onSecurityCheck" then
  ->[true] "Page.onInit()"
  
  if "isForward?" then
   ->[no] "Process controls"
   
   if "continue processing?" then
     -->[yes] ===RENDERING===
   else
     -->[no] ===REDIRECT_CHECK===
   endif
   
  else
   -->[yes] ===RENDERING===
  endif
  
  if "is Post?" then
    -->[yes] "Page.onPost()"
    --> "Page.onRender()" as render
    --> ===REDIRECT_CHECK===
  else
    -->[no] "Page.onGet()"
    --> render
  endif
  
else
  -->[false] ===REDIRECT_CHECK===
endif

if "Do redirect?" then
 ->[yes] "redirect request"
 --> ==BEFORE_DESTROY===
else
 if "Do Forward?" then
  -left->[yes] "Forward request"
  --> ==BEFORE_DESTROY===
 else
  -right->[no] "Render page template"
  --> ==BEFORE_DESTROY===
 endif
endif

--> "Page.onDestroy()"
-->(*)

@enduml