code: @Nonnull
    public static Class <?> [] getClassArray (@Nullable final Object... aObjs)
    {
      if (ArrayHelper.isEmpty (aObjs))
        return EMPTY_CLASS_ARRAY;
  
      final Class <?> [] ret = new Class <?> [aObjs.length];
      for (int i = 0; i < aObjs.length; ++i)
        ret[i] = aObjs[i].getClass ();
      return ret;
    }
docs: Get an array with all the classes of the passed object array.
  
  @param aObjs
  The object array. May be <code>null</code>. No contained element may
  be <code>null</code>.
  @return A non-<code>null</code> array of classes.