This code passes basic test cases but exceeding time limit...can you suggest me what i am doing wrong?

 // Complete the activityNotifications function below.
static int activityNotifications(int[] expenditure, int d) {
    int output = 0;
    for (int i = 0; i <= expenditure.length-d; i++) {
        //System.out.println(Arrays.toString(expenditure));
        List<Integer> temp=new ArrayList<>();
        int count = 0;
        for (int j = i; temp.size()<d && j < expenditure.length; j++) {
            temp.add(expenditure[j]);
            ++count;
        }
        if (count == d) {
            Collections.sort(temp);
            float median = getMedian(temp );
            if (i + d < expenditure.length) {
                if (expenditure[i + d] >= (median * 2)) {
                    output++;
                }
            }
        }
    }
    return output;
}

private static float getMedian( List<Integer> temp) {
    if (temp.size() % 2 == 0) {
        int mNo1 = (temp.size() / 2) - 1;
        int mNo2 = (temp.size() / 2) ;
        return (temp.get(mNo1) + temp.get(mNo2))/2f;
    } else {
        return temp.get(temp.size() / 2);
    }
}