spring-rest-api GET returns client's list returns OS list returns specific OS returns specific OS comments POST add specific client add specific OS PUT update specific client update specific OS(status) DELETE delete specific client REQUEST VALIDATIONS valid specific OS post request - null client ID valid specific OS post request - nonexistent client ID valid specific client post request - null name and malformed email Reference Documentation For further reference, please consider the following sections: Official Apache Maven documentation Guides The following guides illustrate how to use some features concretely: Building a RESTful Web Service Serving Web Content with Spring MVC Building REST services with Spring