活动标签(activity label)以冒号开始,以分号结束。
文本格式支持creole wiki语法。
活动默认安装它们定义的顺序就行连接。
@startuml :Hello world; :This is on defined on several **lines**; @enduml
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开始/结束
你可以使用关键字start
和stop
表示图示的开始和结束。
@startuml start :Hello world; :This is on defined on several **lines**; stop @enduml
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也可以使用 end
关键字。
@startuml start :Hello world; :This is on defined on several **lines**; end @enduml
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条件语句
在图示中可以使用关键字if
,then
和else
设置分支测试。标注文字则放在括号中。
@startuml start if (Graphviz installed?) then (yes) :process all diagrams; else (no) :process only __sequence__ and __activity__ diagrams; endif stop @enduml
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也可以使用关键字elseif
设置多个分支测试。
@startuml start if (condition A) then (yes) :Text 1; elseif (condition B) then (yes) :Text 2; stop elseif (condition C) then (yes) :Text 3; elseif (condition D) then (yes) :Text 4; else (nothing) :Text else; endif stop @enduml
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重复循环
你可以使用关键字repeat
和repeatwhile
进行重复循环。
@startuml start repeat :read data; :generate diagrams; repeat while (more data?) stop @enduml
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while循环
可以使用关键字while
和end while
进行while循环。
@startuml start while (data available?) :read data; :generate diagrams; endwhile stop @enduml

还可以在关键字endwhile
后添加标注,还有一种方式是使用关键字is
。
@startuml while (check filesize ?) is (not empty) :read file; endwhile (empty) :close file; @enduml
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并行处理
你可以使用关键字fork
,fork again
和end fork
表示并行处理。
@startuml start if (multiprocessor?) then (yes) fork :Treatment 1; fork again :Treatment 2; end fork else (monoproc) :Treatment 1; :Treatment 2; endif @enduml
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注释
文本格式支持creole wiki语法。
A note can be floating, using floating
keyword.
@startuml start :foo1; floating note left: This is a note :foo2; note right This note is on several //lines// and can contain <b>HTML</b> ==== * Calling the method ""foo()"" is prohibited end note stop @enduml
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标题和图例
你可以给图表(diagram)添加标题、标头、脚注和图例。
@startuml title this is my title if (condition?) then (yes) :yes; else (no) :no; note right this is a note end note endif stop legend this is the legend endlegend footer dummy footer header this is a long __dummy__ header end header @enduml
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颜色
你可以为活动(activity)指定一种颜色。
@startuml start :starting progress; #HotPink:reading configuration files These files should edited at this point!; #AAAAAA:ending of the process; @enduml
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箭头
使用->
标记,你可以给箭头添加文字或者修改箭头颜色。
It's also possible to have dotted, dashed, bold or hidden arrows.
@startuml :foo1; -> You can put text on arrows; if (test) then -[#blue]-> :foo2; -[#green,dashed]-> The text can also be on several lines and **very** long...; :foo3; else -[#black,dotted]-> :foo4; endif -[#gray,bold]-> :foo5; @enduml
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组合(grouping)
通过定义分区(partition),你可以把多个活动组合(group)在一起。
@startuml start partition Initialization { :read config file; :init internal variable; } partition Running { :wait for user interaction; :print information; } stop @enduml
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泳道(Swimlanes)
你可以使用管道符|
来定义泳道。
还可以改变泳道的颜色。
@startuml |Swimlane1| start :foo1; |#AntiqueWhite|Swimlane2| :foo2; :foo3; |Swimlane1| :foo4; |Swimlane2| :foo5; stop @enduml
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分离(detach)
可以使用关键字detach
移除箭头。
@startuml :start; fork :foo1; :foo2; fork again :foo3; detach endfork if (foo4) then :foo5; detach endif :foo6; detach :foo7; stop @enduml
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特殊领域语言(SDL)
通过修改活动标签最后的分号分隔符(;
),可以为活动设置不同的形状。
|
<
>
/
]
}
@startuml :Ready; :next(o)| :Receiving; split :nak(i)< :ack(o)> split again :ack(i)< :next(o) on several line| :i := i + 1] :ack(o)> split again :err(i)< :nak(o)> split again :foo/ split again :i > 5} stop end split :finish; @enduml
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一个完整的例子
@startuml start :ClickServlet.handleRequest(); :new page; if (Page.onSecurityCheck) then (true) :Page.onInit(); if (isForward?) then (no) :Process controls; if (continue processing?) then (no) stop endif if (isPost?) then (yes) :Page.onPost(); else (no) :Page.onGet(); endif :Page.onRender(); endif else (false) endif if (do redirect?) then (yes) :redirect process; else if (do forward?) then (yes) :Forward request; else (no) :Render page template; endif endif stop @enduml
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