Object-Oriented Thought Process, The, Second Edition

Operator Overloading

Some OO languages allow you to overload an operator. C++ is an example of one such language. Operator overloading allows you to change the meaning of an operator. For example, when most people see a plus sign, they assume it represents addition. If you see the equation

X = 5 + 6;

you expect that X would contain the value 11. And in this case, you would be correct.

However, there are times when a plus sign could represent something else. For example, in the following code:

String firstName = "Joe", lastName = "Smith";

String Name = firstName + " " + lastName;

You would expect that Name would contain Joe Smith. The plus sign here has been overloaded to perform string concatenation.

String Concatenation

String concatenation ...