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1 definition found
 for class hierarchy
From The Free On-line Dictionary of Computing (30 December 2018) :

  class hierarchy
  base class
  derived class
      In object-oriented programming, a set of classes
     related by inheritance.  Each class is a "subclass" of another
     class - its "superclass".  The subclass contains all the features
     of its superclass, but may add new features or redefine existing
     features.  The features of a class are the set of attributes (or
     "properties") that an object of that class has and the methods
     that can be invoked on it.
     If each class has a just one superclass, this is called single
     inheritance.  The opposite is multiple inheritance, under which
     a class may have multiple superclasses.  Single inheritance gives
     the class hierarchy a tree structure whereas multiple
     inheritance gives a directed graph.  Typically there is one
     class at the top of the hierarchy which is the "object" class, the
     most general class that is an ancestor of all others and which has
     no superclass.
     In computing, as in genealogy, trees grow downwards, which is why
     subclasses are considered to be "below" their superclasses.
     When invoking a method on an object, the method is first
     looked for in the object's class, then the superclass of that
     class, and so on up the hierarchy until it is found.  Thus a class
     need only define those methods which are specific to it and it
     will inherit all other methods from all its superclasses.  An
     object of the subclass can do everything that an object of the
     superclass can and possible more.
     C++ calls the superclass the "base class" and the subclass the
     "derived class" (not to be confused with a derived type).

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