code: public static <T> boolean containsOnlyNullElements (@Nullable final T [] aArray)
    {
      if (isEmpty (aArray))
        return false;
  
      for (final Object aObj : aArray)
        if (aObj != null)
          return false;
      return true;
    }
docs: Check if the passed array contains only <code>null</code> element.
  
  @param <T>
  element type
  @param aArray
  The array to check. May be <code>null</code>.
  @return <code>true</code> only if the passed array is neither
  <code>null</code> nor empty and if at least one <code>null</code>
  element is contained.