ProductsUModelUML Application Flow DiagramsUML Sequence Diagrams

Altova UModel® 2008 lets you draw UML sequence diagrams that describe the interactions between objects in your application and specify the messages objects send and receive.

Sequence diagrams map the scenarios described by use cases in step by step detail to define how objects collaborate to achieve your application’s goals.

A lifeline in a sequence diagram represents an object and shows all its points of interaction with other objects in events that are important to it. Lifelines start at the top of a sequence diagram and descend vertically to indicate the passage of time. Interactions between objects – messages and replies – are drawn as horizontal direction arrows connecting lifelines. In addition, boxes known as combine fragments are drawn around sets of arrows to mark alternative actions, loops, and other control structures.

When you create a new sequence diagram, UModel® 2008 automatically displays the sequence diagram toolbar for quick access to specialized UML elements including lifelines, combine fragments, gates, message call and reply arrows, message arrows that create new lifelines or destroy existing objects, notes, and more.

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As you create your sequence diagram, entry helpers assist with element size, placement, names, and message text. You can work directly in the main drawing window, or you can edit in the properties helper window.

When you draw elements such as message arrows that define collaborations within your diagram, UModel signals the location of valid connection points. Since a message arrow requires an end point connection to another lifeline, UModel will not let you drop one in the wrong spot.

You can revise a work in process without deleting elements and redrawing them. For instance, you can change the interaction operator of a combined fragment through the properties window.

This feature lets you experiment with different relationships, particularly when your process requires a loop or more complicated control structure.

Since sequence diagrams will be a permanent part of your project documentation, you’ll find handy options in the layout menu to align and resize objects to make your finished diagram as unambiguous as possible. As with all UModel diagram types, you can print your UML sequence diagram at any time, copy a selection or the entire diagram as a bitmap to paste into another application, or save it as a .PNG or .EMF image file.

UModel® 2008 offers flexible options for sequence diagrams to support your UML diagramming style. You can choose to:

• Automatically create a syntactically correct reply whenever a message is added.
• Select Go To Operation from the right-click context menu to assign a message based on an operation listed in the Model Tree.
• Select simple consecutive message numbers or nested (decimal) message numbering via the sequence diagram toolbar.
• Set custom transparent background colors for combined fragments in the Styles helper window.
• Apply time constraints to sequences, using familiar timing diagram notation.

. . . and much more. UModel lets you easily do it all.

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As your sequence diagrams grow to describe complex interactions with many steps, you will probably need to extend lifelines beyond the original drawing pane. UModel® 2008 displays a special lifeline label header bar at the top of the sequence diagram window so you can easily identify lifelines even when the top portion of your diagram has scrolled out of view.

The collection of tools in UModel® 2008 combine to help you draw superior sequence diagrams. Find out for yourself how easy it is to design effective applications – download a free 30-day trial of Altova UModel® 2008 today!