public SELF onStatusClass(Iterable<HttpStatusClass> statusClasses) {
        requireNonNull(statusClasses, "statusClasses");
        checkArgument(!Iterables.isEmpty(statusClasses), "statusClasses can't be empty.");

        final Set<HttpStatusClass> statusClasses0 = Sets.immutableEnumSet(statusClasses);
        onResponseHeaders((ctx, headers) -> statusClasses0.contains(headers.status().codeClass()));
        return self();
    }
Adds the specified {@link HttpStatusClass}es.

<p>When this is used for a {@link CircuitBreakerRule}, and the response status is one of the specified
{@link HttpStatusClass}es, a {@link Response} is reported as a success or failure to a
{@link CircuitBreaker} or ignored depending on the build methods({@code #thenSuccess()},
{@code #thenFailure()} and {@code #thenIgnore()}).
core/src/main/java/com/linecorp/armeria/client/AbstractRuleBuilder.java