April 2019
Intermediate to advanced
360 pages
9h 17m
English
Content preview from Hands-On Design Patterns with Java
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UML class diagram
The following UML class diagram shows the TrainStatus interface, which is implemented by five additional classes. Each of those classes is identical with the exception of the NullObjectTrain class, which will have no functionality:
UML class diagram—null object design pattern implementation
As indicated in the UML class diagram, the WesterTrain, NorthernTrain, EasterTrain, SouthernTrain, and NullObjectTrain classes each implement the TrainStatus interface.
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