Non-comparison sort for bounded integer keys.

Overview

Non-comparison sort for bounded integer keys.

Example 

  public static void bubbleSort(int[] arr) {
    for (int i = 0; i < arr.length - 1; i++)
        for (int j = 0; j < arr.length - 1 - i; j++)
            if (arr[j] > arr[j + 1]) {
                int tmp = arr[j]; arr[j] = arr[j + 1]; arr[j + 1] = tmp;
            }
}

Common Use Cases

  • Educational purposes
  • Small datasets
  • Nearly sorted data (insertion/bubble)

Pitfalls to Avoid

  • O(n²) is too slow for large inputs
  • Not stable unless implemented carefully
  • Merge Sort
  • Quick Sort
  • Arrays.sort() internals

Best Practices

  • Understand when to use counting sort versus simpler alternatives
  • Write unit tests covering edge cases and failure paths
  • Follow Java conventions and prefer standard library APIs when available
  • Profile before optimizing — measure impact in your specific workload