Radix Sort Implementation in Java

RadixSort.java

private static void radixSort(int array[]) {
  int max = array[0];
  for (int i = 1; i < array.length; i++) {
    if (array[i] > max) {
      max = array[i];
    }
  }

  for (int i = 1; max / i > 0; i *= 10) {
    countingSort(array, i);
  }
}

private static void countingSort(int arr[], int place) {
    int[] output = new int[arr.length + 1];

    int max = arr[0];
    for (int i = 1; i < arr.length; i++) {
        if (arr[i] > max)
            max = arr[i];
    }
    int[] count = new int[max + 1];

    for (int i = 0; i < max; ++i) {
        count[i] = 0;
    }

    for (int i = 0; i < arr.length; i++) {
        count[(arr[i] / place) % 10]++;
    }

    for (int i = 1; i <= 10; i++) {
        count[i] += count[i - 1];
    }

    for (int i = arr.length - 1; i >= 0; i--) {
        output[count[(arr[i] / place) % 10] - 1] = arr[i];
        count[(arr[i] / place) % 10]--;
    }

    for (int i = 0; i < arr.length; i++) {
        arr[i] = output[i];
    }
}