Chloe & Meiko
Meiko
Hey Chloe, there's this old script that keeps throwing an obscure error every time I run it. I'm trying to trace why a variable flips to null after the loop. Want to help me debug?
Chloe
Sure thing! Drop the snippet or the loop that’s doing the flipping, and let’s walk through it together. Usually it’s something like a scope mix‑up or an accidental assignment inside the loop. If you can show where the variable is first set and where it ends up null, I’ll point out any hidden side‑effects or missing initializations. Let’s get it sorted!
Meiko
Here’s the bit that’s tripping me up
Integer flag = 0;
for (int i = 0; i < 5; i++) {
if (i == 2) {
flag = i; // set it to a number
}
if (i == 3) {
flag = null; // accidental reset to null
}
}
System.out.println(flag); // prints null even though it was set before
The null assignment inside the loop is the obvious culprit. Is that the sort of thing you see?
Chloe
Yep, that’s exactly what’s happening. The loop keeps running after you set it to 2, hits the i==3 block, and flips it back to null. As soon as the loop ends, flag is null. If you only wanted it set once, move that null‑assignment out of the loop or add a break or change the condition. Once you stop resetting it, the final print will show 2. Just clean up that stray null line and you’re good to go.
Meiko
That’s the whole story, so pretty simple. If you want to keep the flag at 2 after the loop, either move the null assignment out, or change the logic to avoid touching it after i == 2. A break or an else-if would do the trick. Let me know if you want a refactored version.
Chloe
Sounds solid—just a tiny tweak and you’re done. If you want, I can send a quick refactor that uses an else if or a break to keep flag at 2. Let me know!