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2.10 Trying out the "ShuffledWordLibrary" That Does Not Really Shuffle

Juppies 2 by Dr Heinz M. Kabutz

When coding, it pays to advance slowly and carefully. We now change our WordLibraries facade to instead return our ShuffledWordLibrary that wraps our old StaticWordLibrary. We run the code and verify that everything still runs as before, with the order of the words still the same. We should also run our unit test to make sure that the words all match.

Note: The facade design pattern makes complex subsystems easier to use. In Java, we use this pattern a lot, and it is characterized by a class with only static methods and a private constructor. You will see this in java.util.Collections, java.util.Arrays, java.util.concurrent.Executors, etc. Any class that is written in plural is a likely candidate.


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