An event is an observable occurrence. In the
UML metamodel it is a child of ModelElement
.
There are a number of different types of events that are children of event within the UML metamodel.
SignalEvent
. Associated with a signal,
this event is caused by the signal being raised.
CallEvent
. Associated with an
operation of a class, this event is caused by a call to the given
operation. The expected effect is that the steps of the operation will
be executed.
TimeEvent
. An event cause by
expiration of a timing deadline.
ChangeEvent
. An event caused by a
particular expression (of attributes and associations) becoming
true.
An event is represented by its name.
![]() | Caution |
---|---|
The V0.14 release of ArgoUML does not allow entry of the parameters of the event. |
![]() | Caution |
---|---|
The V0.14 release of ArgoUML has only partially implemented events. In practice, only the name can be specified, there is no difference between the 4 kinds of events described above. The name field should be used to indicate that it is a signal, call, timing or change event. |
The details tabs that are active for events are as follows.
ToDoItem
Standard tab.
Properties
See Section 19.6.2, “Event Property Toolbar” and Section 19.6.3, “Property Fields For Event” below.
Documentation
Standard tab.
Source
Standard tab.
![]() | Note |
---|---|
In the fullness of time this tab will contain code to implement the event. This is not implemented in the V0.14 release of ArgoUML. |
Constraints
Standard tab. ArgoUML only supports constraints on Classes and Features (Attributes, Operations, Receptions, and Methods), so this tab is grayed out.
Tagged Values
Standard tab.
In the UML metamodel,
an Event
has the following standard
tagged values defined.
derived
(from the
superclass, ModelElement
). Values
true
, meaning the call event is
redundant—it can be formally derived from other
elements, or false
meaning it
cannot.
![]() | Note |
---|---|
Derived call events still have their value in analysis and design to introduce useful names or concepts, and in design to avoid re-computation. |
![]() | Note |
---|---|
The UML |
Go
up
Navigate up through the package structure.
Add
parameter
This creates a new parameter for the event operation as the current parameter, navigating immediately to the properties tab for that parameter (see Section 17.8, “Parameter”).
![]() | Warning |
---|---|
This feature is currently broken within ArgoUML and there is no way to enter parameters. |
Name
Text box. The name of the event. By convention event names start with a lower case letter and use bumpy caps to divide words within the name in the same way as operations.
![]() | Note |
---|---|
ArgoUML does not enforce this naming convention. |
![]() | Tip |
---|---|
For call events it makes sense to use the name of the
associated operation. For signal events it make sense to use
the name of the signal, prefixed by
|
Stereotype
Drop down selector.
An Event has no stereotypes
by default in the UML standard,
except when the Event is a Call Event.
For a Call Event, the following stereotypes are defined:
create
and
destroy
.
Navigate Stereotype
icon.
If a stereotype has been selected,
this will navigate to the
stereotype property panel (see Section 15.4, “Stereotype”).
Parameters
Text area, with entries for all the actual parameter values of the event (see Section 17.8, “Parameter”).
Button 1 double-click on any of the parameters navigates to that parameter, button 2 click brings up a pop up menu with four entries.
New
.
Create a new parameter
and navigate to it.
Move Up
. Only available where
there are two or more parameters, and the parameter selected is
not at the top. It is moved up one.
Move Down
. Only available where
there are two or more parameters listed, and the parameter
selected is not at the bottom. It is moved down
one.
Delete From Model
.
Deletes the selected parameter from the model.
Operations
Only present for a Call Event. The V0.14 release of ArgoUML does not allow entry of the operation.