Question

I don’t understand why java thinks the array “thisRow” is void when it is passed into Arrays.sort(thisRow). “thisRow” appears to be an int[] to me. What is the issue here?

Error Message: “Type mismatch: cannot convert from void to int[] at Test.mySort(Test.java:57)”

private static int[][] mySort(int[][] anArray) {
    for(int i = 0; i < anArray.length; i++){
        int thisRow[] = getRow(anArray, i);
        int[] sorted = Arrays.sort(thisRow);
    }
}

//This method will get the specified row out of the array.
private static int[] getRow(int[][] anArray, int row) {
    int thisRow[] = new int[anArray[row].length];
    for(int j = 0; j < anArray[row].length; j++){
        thisRow[j] = anArray[row][j];
    }
    return thisRow;
}

Answer 1

Arrays.sort returns void not int[] type.

As per javadoc

Sorts the specified array of ints into ascending numerical order. The
sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley
and M. Douglas McIlroy’s “Engineering a Sort Function”,
Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November
1993). This algorithm offers n*log(n) performance on many data sets
that cause other quicksorts to degrade to quadratic performance

Replace

int[] sorted = Arrays.sort(thisRow);

with

Arrays.sort(thisRow);