code: public InterceptorConfigurationBuilder index(int i) {
        if (i < 0) throw new IllegalArgumentException("Index cannot be negative");
        attributes.attribute(INDEX).set(i);
        return this;
     }
docs: Specifies a position in the interceptor chain to place the new interceptor.  The index starts at 0 and goes up to
  the number of interceptors in a given configuration.  An {@link IllegalArgumentException} is thrown if the index is
  less than 0 or greater than the maximum number of interceptors in the chain.
  
  @param i positional index in the interceptor chain to place the new interceptor.