Java Learning 2

Looping

Java has three standard Looping constructs: while,

do-while, and for. You'll get the full loop scoop later

in the book, but not for awhile, so let's do while for

now.

The syntax (not to mention logic) is so simple

you're probably asleep already. As long as some

condition is true, you do everything inside the

loop block. The loop block is bounded by a pair of

curly braces, so whatever you want to repeat needs

to be inside that block.

The key to a loop is the conditional test. In Java, a

conditional test is an expression that results in a

boolean value-in other words, something that is

either true or false.

You can do a simple boolean test by checking

the value of a variable, using a comparison operator

including:

< (less than)

> (greater than)

== (equality) (yes, that's two equals signs)

Notice the difference between the assignment

operator (a single equals sign) and the equals

operator (two equals signs).

Int x = 4 ;

while ( x > 3)

{

//loop code will run because

//x is greater than 3

x = x -1 ; // or we’d loop forever

}