private boolean containsOrdinal(int ordinal) {
      int wordIndex = ordinal >>> POWER_OF_TWO_WORD_BITS;
      int bitIndex = ordinal - (wordIndex << POWER_OF_TWO_WORD_BITS);
      return (wordIndex < vector.length) && ((vector[wordIndex] >>> bitIndex) & 1) != 0;
    }
Will throw an exception and leave the collection unmodified.
@throws UnsupportedOperationException always
@deprecated Modification operation are not supported.
ordinal/src/org/immutables/ordinal/ImmutableOrdinalSet.java