Short Circuit AND question (code included)

Question

I have a quick question about the short circuit AND operator...
public class prac1 {
     public static final int aNumber = 19;
     public int age = 53;
     public static void main(String args[]) {
          if ((aNumber == 18) && (aNumber != 10)) {
               System.out.println("You got it!");
}You see I learned that Short Circuit AND means the first expression is evaluated and if it's false the 'code' is executed...
So here is what I am understanding: if((aNumber == 18) already evaluates to false, right, but then I see it as && sees that it's false, but then shouldn't the code execute?
Most likely the case: if((aNumber == 18) already evaluates to false, and because && only evaluates false expressions, and therefore since it's false the code doesn't execute... Am I correct?
Just trying to get the && and || down... Thanks!
Edited by: JavaPWNZ on Jul 2, 2008 5:58 AM

Answer 1

sc3sc3 wrote:
PhHein wrote:
Hi,
a bit confusing, but sort of yes. The && evaluates the first part ((aNumber == 18)) if that is false the following condition is not evaluated any more bacause the whole statement is false.
Try this: String s = null;
if(s != null && s.length() > 0){
System.out.println("Here");
}now try:
String s = null;
if(s != null & s.length() > 0){
System.out.println("Here");
nullpointer :-)As intended :)