Collaboration-Specific Toolbox Icons

Links

Objects interact through their links to other objects. A link is an instance of an association, analogous to an object being an instance of a class.

A link should exist between two objects, including class utilities, only if there is a relationship between their corresponding classes. The existence of a relationship between two classes symbolizes a path of communication between instances of the classes: one object may send messages to another.

Links can support multiple messages in either direction. If a message is deleted, the link remains intact.

The link is depicted as a straight line between objects or objects and class instances in a collaboration diagram. If an object links to itself, use the loop version of the icon.

To create a link between two objects:

1 Click the Link tool.

2 Drag the pointer between the two object icons.

Rational Rose will create and display an unnamed link.

To create a reflexive link (a link between an object and itself):

1 Click the Link to Self tool.

2 Click an icon representing the object.

Rational Rose will create and display an unnamed reflexive link.

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Sequence Numbering

Sequence numbering allows you to clearly see how messages interact and relate to one another. Numbering messages can be done two ways on sequence diagrams: top level numbering (a 1, 2, 3 pattern) or hierarchical numbering (a 1.1, 1.1.2, 1.1.3 pattern). Only top level numbering is available on collaboration diagrams. However, if you create a collaboration diagram from a sequence diagram with hierarchal numbering, the hierarchal numbering is retained.