• Use a dashed arrow between classes to show a dependency that does not use an object
reference. For example, the Customer class uses a static method from the
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Figure C.3 shows the basic features for illustrating interfaces. Following are notes on
Figure C.3. You can indicate an inter-face with either an «interface» stereotype or
• You can draw an interface by placing the text «interface» and the name of
the interface in a rectangle, as Figure C.3 shows. You can use a dashed line and a
closed, hollow arrowhead to show that a class implements the interface.
• You can also show that a class implements an interface by showing a line and circle,
or "lollipop," and the name of the interface.
• Interfaces and their methods are always abstract in Java. Oddly enough, interfaces and
their methods do not appear in italics, unlike abstract classes and abstract methods in
An object diagram illustrates specific instances of classes, as Figure C.4 shows. Following are
notes on object diagrams.