Question

java.lang.NullPointerException
    at java.lang.Integer.compareTo(Unknown Source)
    at java.lang.Integer.compareTo(Unknown Source)

I slightly edited my code, deleted no methods but changed the name of one or two, and now…boom! Nothing works ! So annoying because I just had it working, went back and commented it and now I can’t see whats changed…help ? 🙂

Answer 1

You’re probably trying to do something like this:

Integer i = null;
Integer j = 42;
i.compareTo(j); // throws NullPointerException since i is null

or this:

Integer i = 21;
Integer j = null;
i.compareTo(j); // throws NullPointerException since j is null

but you haven’t shown any code.