code: @Nullable
    @ReturnsMutableCopy
    public static <ELEMENTTYPE> ELEMENTTYPE [] getConcatenated (@Nullable final ELEMENTTYPE [] aHeadArray,
                                                                @Nullable final ELEMENTTYPE [] aTailArray)
    {
      // If first array is invalid, simply
      if (isEmpty (aHeadArray))
        return getCopy (aTailArray);
      if (isEmpty (aTailArray))
        return getCopy (aHeadArray);
  
      // Start concatenating
      final ELEMENTTYPE [] ret = newArraySameType (aHeadArray, aHeadArray.length + aTailArray.length);
      System.arraycopy (aHeadArray, 0, ret, 0, aHeadArray.length);
      System.arraycopy (aTailArray, 0, ret, aHeadArray.length, aTailArray.length);
      return ret;
    }
docs: Get a new array that combines the passed two arrays, maintaining the order.
  
  @param <ELEMENTTYPE>
  Array element type
  @param aHeadArray
  The first array. May be <code>null</code>.
  @param aTailArray
  The second array. May be <code>null</code>.
  @return <code>null</code> if both array parameters are <code>null</code> -
  a non-<code>null</code> array with all elements in the correct
  order otherwise.