The operator is undefined

Question

I just tried to make a simple class that lets me figure out the length of a file: ``` public class Size { long s = 0; int a; public static void main(String[]args){ new Size(); } Size(){ try{ FileInputStream str = new FileInputStream("E:/Eclipse/Resources/smile.jpg"); while(a != null){ s++; } }catch (IOException e){ e.printStackTrace(); } } } ``` I run into a problem with ``` while(a != null) ``` I get the Error: The operator != is undefined for the argument type(s) int, null Any ideas why it's blocking the condition?

Accepted Answer

Primitive types in Java cannot be `null`. If you want to check for 0, do `a != 0`.

The operator is undefined

Solution

Problem