Write a Java program modifying the standard Merge Sort algorithm to perform the merging of the two subarrays in-place, without using any additional memory for creating temporary arrays. The goal is to reduce the overall space complexity of the algorithm.

public static void main(String[] args) {
    int[] nums = {0, 1, 2, 3, 4, 5, 6};
    mergeSort(nums, 0, nums.length - 1);
    System.out.println(Arrays.toString(nums));
}

private static void mergeSort(int[] nums, int left, int right) {
    if (left < right) {
        int mid = (left + right) / 2;
        mergeSort(nums, left, mid);
        mergeSort(nums, mid + 1, right);
        merge(nums, left, mid, right);
    }
}

private static void merge(int[] nums, int left, int mid, int right) {
    while (left <= mid && mid + 1 <= right) {
        if (nums[left] <= nums[mid + 1]) {
            left++;
        } else {
            int temp = nums[mid + 1];
            for (int i = mid + 1; i > left; i--)