The modulus Operators
The modulus operator, % returns the remainder of a division operation. It
can be applied to floatingpoint types as well as integer types. (This differs
from C/C++, in which the % can only be applied to integer types.) The following
example program demonstrates the %:
//Demonstrate
the % operator.
class
Modulus {
public static void main ( String args[]) {
int x = 42;
double y = 42.25;
System.out.println(“x mod 10 = “ + x % 10);
System.out.println(“y
mod 10 = “ + y % 10);
}
}
When you run this program you will get the following
output:
x mod 10 = 2
y mod 10 = 2.25
Arithmetic Assignment Operators
Java provides special operators that can be used to combine an arithmetic
operation with an assignment. As you probably know, statements like the
following are quite common in programming
a = a+4;
in java, you can rewrite this statement as shown here.
a +=4;
This version uses the += assignment operator. Both
statements perform the same action: they increase the value of a by 4.
Here is another example,
a = a % 2;
Which can be expressed as
a %= 2;
In this case, the %= obtains the remainder of a/2 and puts
that result back into a.
There are assignment operators provide two benefits. First, they save you
a bit of typing, because they are “shorthand” for their equivalent long
forms. Second, they are implement more efficiently by the java runtime system
than are their equivalent long forms.
