The
Java programming language supports overloading methods, and Java can
distinguish between methods with different method signatures. This means
that methods within a class can have the same name if they have different
parameter lists (there are some qualifications to this that will be discussed
in the lesson titled "Interfaces and Inheritance").
Suppose
that you have a class that can use calligraphy to draw various types of data
(strings, integers, and so on) and that contains a method for drawing each data
type. It is cumbersome to use a new name for each method—for example, drawString, drawInteger, drawFloat, and so on. In the
Java programming language, you can use the same name for all the drawing methods
but pass a different argument list to each method. Thus, the data drawing class
might declare four methods named draw, each of which has a different
parameter list.
public class DataArtist {
...
public void
draw(String s) {
...
}
public void draw(int i) {
...
}
public void
draw(double f) {
...
}
public void draw(int
i, double f) {
...
}
}
Overloaded
methods are differentiated by the number and the type of the arguments passed
into the method. In the code sample, draw(String s) and draw(int i) are distinct and
unique methods because they require different argument types.
You
cannot declare more than one method with the same name and the same number and
type of arguments, because the compiler cannot tell them apart.
The
compiler does not consider return type when differentiating methods, so you
cannot declare two methods with the same signature even if they have a
different return type.
