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Each party in an interaction is represented by a target. In other words, a target is something that can be communicated with during an interaction.

Target kind

Each target is of a certain kind which determines what it represents and how it looks. Trace Modeler supports the following kinds :

UML sequence diagram showing the different kinds of target (non-icon)

If you're not modeling software objects, you'll only need the three kinds of objects and have little use for classes.

Some often used object stereotypes can be represented by icons :

UML sequence diagram showing the different kinds of targets (icons)

You can change the size of these icons with the 'Target icon size' property of a diagram style.

If you want to use a stereotype for which no icon is available (or prefer not to use icons), simply add the stereotype on a separate line at the top of the target label.

UML sequence diagram of a target with a stereotype


Target label

Each target has a label that describes it and can span multiple lines. It usually consists of a single line, but if you need to add a stereotype or save some horizontal space you'll want to use multiple lines of text.


Target lifeline

Trace Modeler will automatically determine the correct length of each target's lifeline.


Target order

The order in which targets are shown on the diagram not only affects how your diagram looks, but also how easy it is to understand it.

The target order combined with the diagram style properties 'Lifeline spacing' and 'Layout direction' determines the horizontal location of each target.

Reordering targets is easy with Trace Modeler : simply rearrange them on the diagram and everything else will be adjusted accordingly.

You can reorder the targets by changing the relative positions of individual targets or let Trace Modeler optimize the order based on some heuristics.


Target destruction

The destruction of a target is shown on the diagram by placing a cross on its lifeline and ending the lifeline at that point in time.

Trace Modeler gives you three different ways to effect its demise by setting its destruction property to one of the following :

The following UML sequence diagram shows how the different settings influence if and where the cross is placed on the lifelines :

a target's destroy setting determines when (and if) it will be destroyed

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