Use the Class By Pattern button on the diagram element toolbar to implement source code constructions or solutions in your model. The patterns provided with Together include the GoF patterns (Visitor, Observer, and Singleton), a set of EJB classes for various specifications, a set of TagLib patterns, and many others.
To create a class by pattern:
Click the Class By Pattern button 
on the diagram toolbar.
Click on the diagram workspace. The Apply pattern dialog displays:
Select the appropriate pattern from the Patterns tree.
Set each value field within the Parameters area, or to apply default values, click Finish.
Click Finish.
Once the pattern displays on the diagram, if desired, you can hide the pattern or its participants. To hide pattern participants, right click the pattern on the diagram, and select Hide Participants from the context menu. Selecting Hide from the pattern context menu hides the pattern from view.
To display hidden patterns or pattern participants, right click on the diagram background, and select Hide / Show from the context menu. The Show Hidden dialog displays. Use this dialog to move hidden elements back to the diagram view. For more information, see Hiding Elements.
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