code: @Nonnull
    @MayContainNull
    @Weight(Weight.Unit.NORMAL)
    public static <T> T[] joinArrays(@MayContainNull final T[]... arrays) {
      int commonLength = 0;
      for (final T[] array : arrays) {
        if (array != null) {
          commonLength += array.length;
        }
      }
      @SuppressWarnings("unchecked")
      final T[] result = (T[]) Array.newInstance(arrays.getClass().getComponentType().getComponentType(), commonLength);
      int position = 0;
      for (final T[] array : arrays) {
        if (array != null) {
          System.arraycopy(array, 0, result, position, array.length);
          position += array.length;
        }
      }
      return result;
    }
docs: Join arrays provided as parameters, all arrays must be the same type, null
  values allowed.
  
  @param <T> type of array
  @param arrays array of arrays to be joined
  @return all joined arrays as single array
  @since 1.0