code: public static ProviderContextBuilder of(String provider, Collection<RateType> rateTypes) {
          return new ProviderContextBuilder(provider, rateTypes);
      }
docs: Create a new ProviderContextBuilder instance.
  
  @param provider  the provider name, not {@code null}.
  @param rateTypes the rate types, not null and not empty.
  @return a new {@link javax.money.convert.ProviderContextBuilder} instance, never null.