Edge cases: NullPointerException
Of all possible edge cases, the null variable one, where an object has not been set, is the one that tends to sneak up
on programmers the most. It can arise for many reasons: someone forgot to initialize a variable, an object did not form
properly, someone filled in a website form incorrectly, … The list goes on and on.
In Java, when a method is called on a null variable, a NullPointerException is thrown.
In this exercise, try to trigger a NullPointerException in the given code.
Cet exercice fait partie du cours
Introduction to Testing in Java
Instructions
- Call a method on
namethat will result in aNullPointerExceptionbeing thrown.
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
public class NullPointer {
private static String name;
public static void main(String[] args) {
// Call a method on name that will throw a NullPointerException
System.out.println("My name has " + name.____ + " characters.");
}
}