ProductsUModelUML Application Flow DiagramsUML Sequence Diagrams

Altova UModel® 2012 lets you draw UML sequence diagrams that describe the interactions between objects in your application and specify the messages objects send and receive.

A sequence diagram can map a scenarios described by a use case 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.

Altova UModel Features Overview

Altova UModel® 2012 is an intuitive, affordable, and fully featured tool to create UML sequence diagrams, and to leverage all the additional advantages of UML-based software development. UModel supports these advanced features:

• All 14 UML diagram types, plus a UML-style diagram for XML Schemas, and business process (BPMN) modeling
• Generate application source code in Java, C#, and Visual Basic languages
• Reverse engineer existing Java, C#, and Visual Basic applications
• XMI 2.1 interchange standard for UML models
• Automatically generate comprehensive, customizable project documentation
• Tight integration with Visual Studio and Eclipse
• And much more . . .

 Click here to download a fully functional, free 30-day trial of Altova® UModel® 2012!

Sequence Diagrams in Altova UModel

When you create a new sequence diagram, UModel® 2012 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.

Creating Operations in Referenced Classes

When you add a new message to a lifeline that represents a class, you may assign a message name or use the operation pull-down list in the Properties helper window to assign an existing operation from the target class.

If you turn on Automatic Creation of Operations in the Sequence Diagram toolbar, you can create a new operation in the target class by typing the new operation in the message in your sequence diagram.

Flexible Sequence Diagram Layout

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® 2012 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® 2012 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.

Automatic Generation of Sequence Diagrams

UModel® 2012 lets you generate sequence diagrams from source code files that have been reverse engineered into UML classes. These detailed diagrams will greatly enhance traceability and accelerate analysis, reuse, debugging, or enhancement of legacy applications. You can easily generate multiple sequence diagrams in a single step by selecting operations in reverse engineered classes from the model tree.

The resulting sequence diagrams can be an invaluable tool to quickly and easily expose multiple operations for visual examination, facilitating analysis of large, complex applications.

The UModel overview helper window displays color shading to help you quickly see nested logic in code represented in the sequence diagram. You can drag the red box in the overview window to select your view in the main diagram window.

Sequence diagrams may be generated from Java, C#, or Visual Basic application code. Click here for more information on UModel reverse engineering capabilities.

The Sequence Diagram Generation dialog offers a choice that will be very useful if you plan to modify an existing application. You can choose to automatically update the sequence diagram each time you modify source code outside UModel and synchronize your UML project with the updated code.

The Sequence Diagram Generation dialog also lets you enter a comma delimited list of operations that will not appear in the generated sequence diagram.

Code Generation from Sequence Diagrams

UModel empowers developers to generate code from sequence diagrams for methods that describe class operations. This functionality greatly enhances UModel as a visual design and code generation tool, since you can insert entire code bodies in sequence diagrams and create a complete executable application, rather than a starting point that requires further hand-written code.

You can generate source code from new sequence diagrams when forward engineering a new design, you update existing code by revising sequence diagrams that were reverse-engineered, and you can even apply round-trip engineering to synchronize later changes to either the source code or sequence diagrams in your UML model.

The class diagram below illustrates a new class that defines a single operation called max.

You can use the right-click context menu to generate a new empty sequence diagram for the max operation.

Next, you can design the operation using UML modeling elements. In the screen shot below, a UML alt block defines a simple if-then-else method for the class operation. The Properties window for each UML note element specifies whether the note contains code or is an ordinary annotation. In the diagram, shaded corners indicate notes with code.

During forward engineering code generation, a complete method body is written to the source code file. The example below shows the code for the new Class1 in Java.

UModel code generation from sequence diagrams is supported for Java, C#, and Visual Basic languages. For more information on UModel code generation, visit the UML code engineering section.

SysML Sequence Diagrams

UModel also supports SysML sequence diagrams, which extend UML sequence diagrams by adding the SysML allocate element. Click here to read more about support for SysML in UModel® 2012.

The collection of tools in UModel® 2012 combine to help you draw superior sequence diagrams. Find out for yourself how easy it is to design effective applications:

 Click here to download a fully functional, free 30-day trial of Altova® UModel® 2012 today!