Java Reference
In-Depth Information
The important difference between the
while
and
do-while
loops involves when the
controlling Boolean expression is checked. With a
while
statement, the Boolean expres-
sion is checked
before
the loop body is executed. If the Boolean expression evaluates to
false
, then the body is not executed at all. With a
do-while
statement, the body of the
Display 3.7
Demonstration of
while
Loops and
do-while
Loops
(part 1 of 2)
1
public
class
WhileDemo
2{
3
public
static
void
main(String[] args)
4
{
5
int
countDown;
6
System.out.println("First while loop:");
7
countDown = 3;
8
while
(countDown > 0)
9
{
10
System.out.println("Hello");
11
countDown = countDown - 1;
12
}
13
System.out.println("Second while loop:");
14
countDown = 0;
15
while
(countDown > 0)
16
{
17
System.out.println("Hello");
18
countDown = countDown - 1;
19
}
20
System.out.println("First do-while loop:");
21
countDown = 3;
22
do
23
{
24
System.out.println("Hello");
25
countDown = countDown - 1;
26
}
while
(countDown > 0);
27
System.out.println("Second do-while loop:");
28
countDown = 0;
29
do
30
{
31
System.out.println("Hello");
32
countDown = countDown - 1;
33
}
while
(countDown > 0);
34
}
35
}
(continued)
