private DocServiceBuilder exampleHeaders0(String serviceName, String methodName,
                                              Iterable<? extends HttpHeaders> exampleHeaders) {
        for (HttpHeaders h : exampleHeaders) {
            requireNonNull(h, "exampleHeaders contains null.");
            this.exampleHeaders.computeIfAbsent(serviceName, unused -> ArrayListMultimap.create())
                               .put(methodName, h);
        }
        return this;
    }
Adds the example {@link HttpHeaders} for the method with the specified service and method name.
core/src/main/java/com/linecorp/armeria/server/docs/DocServiceBuilder.java