javaNull / UndefinedEasy

NullPointerException on unboxing null Integer

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BugFind the bug and fix the code

What it should do

Extract score or return default 0 if null. Example: parseIntegerScore(null) -> 0

What happens instead

java.lang.NullPointerException during auto-unboxing of Integer wrapper to primitive int

public class Main {
    public static int parseIntegerScore(Integer score) {
        // Auto-unboxing score to int calls score.intValue(), which throws NPE if score is null
        int val = score;
        return val;
    }

    public static void main(String[] args) {
        System.out.println(parseIntegerScore(null));
    }
}

Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).

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This bug belongs to the null and undefined errors pattern

Cannot read properties of undefined, NoneType has no attribute, NaN appearing from nowhere.

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public class Main { public static int parseIntegerScore(Integer score) { // Auto-unboxing score to int calls score.intValue(), which throws NPE if score is null int val = score; return val; } public static void main(String[] args) { System.out.println(parseIntegerScore(null)); } }

NullPointerException on unboxing null Integer

What it should do

What happens instead

More null and undefined errors to practise

Seen this error in your own code?

NullPointerException on unboxing null Integer

What it should do

What happens instead

More null and undefined errors to practise

Seen this error in your own code?