Resumen
Inheritance is commonly viewed as a problem in which semantic relations mix with design concepts and the particular mechanisms of programming languages. But inheritance is more than a source of ambiguity and misunderstanding. We see another serious issue: Correct behavior of a system of objects is commonly endangered by the implementation of inheritance. Thus, the system of objects surrenders to the risk of synchronization faults that may generate nonsense data and may result in information losses, deadlocks, and so forth. Programmers says the term generalization refers to the relationship among class and the term inheritance refers to the mechanism of obtaining attributes and operations using the generalization structure. Generalization provides the means for refining a superclass into one or more subclasses. Superclass contains features common to all classes; the subclasses contain features specific to each class. Inheritance may occur at an arbitrary number of levels where each level represents one aspect of an object. An object accumulates features from each level of a generalization hierarchy.