Methods are divided roughly into procedures and functions.
Most of the methods that we've already seen in the exercises are procedures. A procedure is a block of code where the main aim is to do something, such as print out text. For example:
void print (int n)
{
System.out.println("n = " + n);
}
The word void means that the method doesn't return a result.
The word print is the name of the method, and it is very common
for programmers to pick a verb for this. Then comes the argument list, giving
the type and name of each argument. Then comes the block of code to be carried
out.
With a function, the main aim is to return a result. For example, this method squares a number:
int square (int n)
{
return n*n;
}
The differences between this and a procedure are the result
type and the return statement. The first word, instead of
being void, tells you what type of value the method returns. The
method ends by returning a result expression.