static Message.Builder getMessageBuilder(Class<?> clazz) {
        final MethodHandle methodHandle = methodCache.get(clazz);
        if (methodHandle == unknownMethodHandle) {
            throw new IllegalStateException("Failed to find a static newBuilder() method from " + clazz);
        }
        try {
            return (Message.Builder) methodHandle.invoke();
        } catch (Throwable throwable) {
            throw new IllegalStateException(
                    "Failed to create an empty instance of " + clazz + " using newBuilder() method", throwable);
        }
    }
Creates an instance with the specified {@link Parser} and {@link ExtensionRegistry}.
protobuf/src/main/java/com/linecorp/armeria/server/protobuf/ProtobufRequestConverterFunction.java