Polymorphism
Finally, objects have a sense of their ancestry and can "polymorph" or "down caste" as the situation demands. That is, any "cat" object can work as a "mammal" object when required to do so.
In a nutshell, polymorphism is bottom-up method calling.
The benefit of polymorphism is that it is very easy to add new classes of derrived objects without breaking your code.
For example, if you had a method like maintainBodyTemp() that took as a parameter an object derrived from the mammal class, then you could always add new mammal objects without breaking the method.
Okay, well enough of all this abstract OOD theory.
The best way to understand OOD is to do it and build up an intuition for it.
Let's do so!
In the next tutorial we will look at getting you started with Java....
Selena Sol contributes to the JavaBoutique's Introduction to Java. Selena curently works for Barclays Capital in London, one of the leading global investment banks in Europe and has worked as a software developer for the National Center for Human Genome research, Microline Software, Neuron Data, and Electric Eye in Singapore. Selena is perhaps best-known for creating the Public Domain Web Script Archive (Extropia) and writing several books on Web Programming (Perl, CGI, Java).
Email: selena@extropia.com
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