The Dialer or Line code is listed in only one place in the program, and Java knows exactly which code to execute every time a Dialer object is invoked. In the following example a switch is used in an object to take touch-tone input from a caller. There are many benefits to polymorphism. The main pros are that it allows new objects to be added to a system with minimal changes to the system. Whenever our telephony application requires new dialing procedures we simply instantiate a collection of objects that inherit dialing code from a collection of superclasses.
Polymorphism takes care of the rest.
The syntax and grammar of both languages are almost the same, as is the run-time environment. I don t care too much for the war between Sun and Microsoft. I care about making money and paying the bills. If you are new to Java in particular and programming in general, then I suggest you study Java first. Java is established and has a huge industry behind it.