PartialHealthCheckStrategy build() {
        final EndpointLimitingFunction endpointLimitingFunction;
        if (maxEndpointCount != null) {
            endpointLimitingFunction = EndpointLimitingFunction.ofCount(maxEndpointCount);
        } else if (maxEndpointRatio != null) {
            endpointLimitingFunction = EndpointLimitingFunction.ofRatio(maxEndpointRatio);
        } else {
            throw new IllegalStateException("The maximum endpoint count or ratio must be set.");
        }

        return new PartialHealthCheckStrategy(endpointLimitingFunction);
    }
Returns a newly created {@link PartialHealthCheckStrategy} based on the properties set so far.
core/src/main/java/com/linecorp/armeria/client/endpoint/healthcheck/PartialHealthCheckStrategyBuilder.java