Jakarta RESTful Web Services

Jakarta RESTful Web Services, (JAX-RS; formerly Java API for RESTful Web Services) is a Jakarta EE API specification that provides support in creating web services according to the Representational State Transfer (REST) architectural pattern. JAX-RS uses annotations, introduced in Java SE 5, to simplify the development and deployment of web service clients and endpoints.

From version 1.1 on, JAX-RS is an official part of Java EE 6. A notable feature of being an official part of Java EE is that no configuration is necessary to start using JAX-RS. For non-Java EE 6 environments a small entry in the web.xml deployment descriptor is required.

Specification
JAX-RS provides some annotations to aid in mapping a resource class (a POJO) as a web resource. The annotations use the Java package  (previously was   but was renamed on May 19, 2019 ). They include:
 * specifies the relative path for a resource class or method.
 * ,,  ,   and   specify the HTTP request type of a resource.
 * specifies the response Internet media types (used for content negotiation).
 * specifies the accepted request Internet media types.

In addition, it provides further annotations to method parameters to pull information out of the request. All the  annotations take a key of some form which is used to look up the value required.


 * binds the method parameter to a path segment.
 * binds the method parameter to the value of an HTTP query parameter.
 * binds the method parameter to the value of an HTTP matrix parameter.
 * binds the method parameter to an HTTP header value.
 * binds the method parameter to a cookie value.
 * binds the method parameter to a form value.
 * specifies a default value for the above bindings when the key is not found.
 * returns the entire context of the object (for example ).

JAX-RS 2.0
In January 2011 the JCP formed the JSR 339 expert group to work on JAX-RS 2.0. The main targets are (among others) a common client API and support for Hypermedia following the HATEOAS-principle of REST. In May 2013, it reached the Final Release stage.

On 2017-08-22 JAX-RS 2.1 specification final release was published. Main new supported features include server-sent events, reactive clients, and JSON-B.

Implementations
Implementations of JAX-RS include:
 * Apache CXF, an open source Web service framework
 * Jersey, the reference implementation from Sun (now Oracle)
 * RESTeasy, JBoss's implementation
 * Restlet
 * WebSphere Application Server from IBM:
 * Version 7.0: via the "Feature Pack for Communications Enabled Applications"
 * Version 8.0 onwards: natively
 * WebLogic Application Server from Oracle, see notes
 * Apache Tuscany (http://tuscany.apache.org/documentation-2x/sca-java-bindingrest.html), discontinued
 * Cuubez framework (https://web.archive.org/web/20190707005602/http://cuubez.com/)
 * Everrest, Codenvy's Implementation
 * Jello-Framework, Java Application Framework optimized for Google App Engine, including a powerful RESTful engine and comprehensive Data Authorization model.
 * Apache TomEE, an addition to Apache Tomcat

Tutorials

 * https://javabrains.io/courses/javaee_jaxrs/
 * http://docs.oracle.com/javaee/6/tutorial/doc/giepu.html
 * http://www.vogella.com/tutorials/REST/article.html
 * http://www.mkyong.com/tutorials/jax-rs-tutorials/
 * http://www.coderpanda.com/jax-rs-tutorial/
 * https://www.javavogue.com/2015/03/java-jerseyjax-rs-tutorials/
 * http://howtodoinjava.com/restful-web-service/