Flow Control Quick Reference
A detailed discussion of flow control can be found in the Java Tutorial
Decisions: The If
if ( condition ) {
true case;
}
[ else {
false case;
} ]
Note that the else login is optional
Examples
if ( count = 3 ) {
out.println("Times up!");
}
...
if ( request.getParameter("gst").equals("true") ) {
total = total + cost * amount * 1.07;
} else {
total = total + cost * amount;
}
Loops: The While
while ( condition ) {
true case;
}
Note that unless code in the true case can change the condition, your program will not exit. This is caslled an infinite loop
Examples
int size = 38;
while( size < 10000 ) {
size = size * 2;
}
...
Enumerator enum = request.getParameterNames()
while (e.hasMoreElements()) {
String key = (String)e.nextElement();
String value = getInitParameter(key);
out.println(" " + key + " = " + value);
}
Enumerator is a special class used to step through all the elements of a list.