public static <T extends Comparable<? super T>> void quickSort(T[] data, int min, int max) {
    int indexofpartition;

    if (max > min) {
        /** Create partitions */
        indexofpartition = findPartition(data, min, max);

        /** Sort the left side */
        quickSort(data, min, indexofpartition - 1);

        /** Sort the right side */
        quickSort(data, indexofpartition + 1, max);
    }
}

private static <T extends Comparable<? super T>> int findPartition(T[] data, int min, int max) {
    int left, right;
    T temp, partitionelement;
    int middle = (min + max) / 2;

    partitionelement = data[middle]; // use middle element as partition
    left = min;
    right = max;

    while (left < right) {
        /** search for an element that is > the partitionelement */
        while (data[left].compareTo(partitionelement) < 0) {
            left++;
        }

        /** search for an element that is < the partitionelement */
        while (data[right].compareTo(partitionelement) > 0 ) {
            right--;
        }

        /** swap the elements  */
        temp = data[left];
        data[left] = data[right];
        data[right] = temp;

        /** let left skip elements with the same value as the partition element */
        if(data[left].compareTo(data[right]) == 0
                && left != right){
            left++;
        }
    }
    return right;
}