String validation

[trupti nigam]

Hello all,

In my code I have declared a String name;

An I am doing following validations..
if(name == null)
{doSomething; }
else if(name != null){do Somethign;}

What I have observed is when I write if(name != null)condiiton before if(name == null)condiiton, when the name is not null the if(name != null) condiiton is ignored.
but if works fine as mentioned in the first para.

why is this happening?

thanks,
trupti

[pascal betz]

since a value can be either null or not null there is no need for both conditions:

if (name == null) {
  // do something
} else {
  // do something else
}

is how you can validate your strings.

if the conditions are exclusive, then the order is not important.


pascal

[Ben Ethridge]

I agree with Pascal, but just for the sake of argument, I wrote a simple one:

package bentest;
public class test {
public static void main(String[] args) {
    String name = "Ben";
    if (name != null){
    System.out.println("not null");
    }else if (name == null){
    System.out.println("null");
    } else{
    System.out.println("Warning! Warning! Danger! Danger!");
    }
return;

}
}
  

Works ok for me. You sure there isn't something else going on (maybe some subtlety) in your code?

Point of TV trivia: Who (or should I say what) used to shout the String I have in the else above?

Ben
SCJB 1.4