indexOf returning -1 when it clearly shouldn't

Question

int[] sorted = {10,67,68,28};
int[] sortedOriginal = sorted.clone();
Arrays.sort(sorted);

System.out.println(Arrays.asList(sorted).indexOf(sortedOriginal[0]));

In this very simple code I create an array of ints, clone it, and sort the original. After that I try to find the index given a certain value and it returns -1.

This doesn't make sense. Does anyone know why this happens and what the fix is?

score 5 · Accepted Answer · answered Dec 13 '15 at 08:10

Arrays.asList(sorted) returns a List having a single int[] element. That's the way it works on primitive arrays, so it doesn't contain sortedOriginal[0] (on the other hand Arrays.asList(sorted).indexOf(sorted) would return 0).

If you use Integer[] arrays, your code will work.

indexOf returning -1 when it clearly shouldn't

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