median quicksort using pivot

Question

i have a question regarding my quicksort algorithm, it runs on small arrays but when the arrays get large the program quits running, basically I'm just trying to find the median value, so i keep splitting the array to discard values that I'm not worried about, so I'll use three values to find the best pivot and get that index, then i run quicksort so the values on either side are less or greater than pivot, and then check the pivot index with where the median value should be, for example if i have a 20 index array the median value should be 10, n if my pivot is at index 7 i start a new quicksort from index 7 to 20, n keep recursively running it until the pivotindex is at the median

    // median of three
    private static int getPivot(int[] nums, int left, int right) {
        int[] triplet = new int[] {nums[left], nums[(left + right) / 2], nums[right]};
        Arrays.sort(triplet);
//             pivotIndex is either left, right, or middle
            if(triplet[1] == nums[left]){
                pivotIndex = left;
            }
            else if(triplet[1] == nums[(left + right) / 2]){
                pivotIndex = (left + right) / 2;
            }
            else if(triplet[1] == nums[right]){
                pivotIndex = right;
            }

        return triplet[1];
    }

    // swap two values
    private static void swap(int[] nums, int left, int right) {
        int temp = nums[left];
        nums[left] = nums[right];
        nums[right] = temp;
    }

/// this is the quick sort

Blockquote

     static int median;
   static int pivotIndex;

    public static double findMedian(int[] nums) {
        median = nums.length / 2;
        quicksort(nums, 0, nums.length - 1);
        return (nums[median]);
    }

    private static void quicksort(int[] nums, int left, int right) {

        if (left >= right)
        return;
        int fromLeft = left;
        int fromRight = right;
        int pivot = getPivot(nums, left, right);
        swap(nums, pivotIndex, right);
        pivotIndex = right;
        fromRight--;
        while(fromLeft < fromRight){
            if ( (nums[fromLeft] > pivot) && (nums[fromRight] < pivot)) {
                swap(nums, fromLeft, fromRight);
                fromLeft++;
                fromRight--;
            }
            while (nums[fromLeft] < pivot){
                fromLeft++;
            }
            while (nums[fromRight] > pivot){
                fromRight--;
            }
            if( fromLeft > fromRight){
                pivotIndex = fromLeft;
                swap(nums, fromLeft, right);
            }
        }
        if(pivotIndex == median){
            return;
        }
        if(pivotIndex > median){
            quicksort(nums, left, pivotIndex);
        }
        if(pivotIndex < median){
            quicksort(nums, pivotIndex, right);
        }

da problem i am having is when the number gets big enough is just says the application is running and doesn't do anything and i can't figure out why, even if it took n^2 it should eventually display an anser