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Object-Orientation Abusers
All these smells are incomplete or incorrect application of object-oriented programming principles.
You have a complex switch operator or sequence of if statements.
Temporary fields get their values (and thus are needed by objects) only under certain circumstances. Outside of these circumstances, they’re empty.
If a subclass uses only some of the methods and properties inherited from its parents, the hierarchy is off-kilter. The unneeded methods may simply go unused or be redefined and give off exceptions.
Two classes perform identical functions but have different method names.