JAX-RS(Java™ API for RESTful Web Services)는 자바 플랫폼에서 경량화된 REST 방식의 웹 애플리케이션 구현을 지원하는 자바 API이다.

 SOAP기반의 SOA 연동은 자바 애플리케이션을 무겁게 한다는 비판과 함께, 최근 웹 애플리케이션의 경향인 AJAX기반으로 JSON이나 RSS와 같이 간결한 프로토콜을 사용한 연동이 보편화되면서 쉽게 구현할 수 있도록 Java EE에 JAX-RS 라는 사양이 포함되고 있다.

(출처 : 위키피디아 http://ko.wikipedia.org/wiki/JAX-RS)

 구현체로는

• Restlet
• JBoss RESTEasy
  RESTEasy is a JBoss project that provides various frameworks to help you build RESTful Web Services and RESTful Java applications. It is a fully certified and portable implementation of the JAX-RS specification. JAX-RS is a new JCP specification that provides a Java API for RESTful Web Services over the HTTP protocol.
  RESTEasy can run in any Servlet container, but tighter integration with the JBoss Application Server is also available to make the user experience nicer in that environment. While JAX-RS is only a server-side specification, RESTEasy has innovated to bring JAX-RS to the client through the RESTEasy JAX-RS Client Framework. This client-side framework allows you to map outgoing HTTP requests to remote servers using JAX-RS annotations and interface proxies.
• Apache CXF
  Apache CXF is an open source services framework. CXF helps you build and develop services using frontend programming APIs, like JAX-WS and JAX-RS. These services can speak a variety of protocols such as SOAP, XML/HTTP, RESTful HTTP, or CORBA and work over a variety of transports such as HTTP, JMS or JBI.
  CXF(CeltiXfire) 정보 : http://xfire.codehaus.org/XFire+and+Celtix+Merge
  spring cxf2.0 - jax-rs : http://jcjang.tistory.com/55
  Spring2.5 and CXF2.0 : http://wheelersoftware.com/articles/spring-cxf-web-services.html
  또 다른 CXF Tutorial : http://www.theasolutions.com/tutorials/cxfuploadattachment.jsp
  http://cwiki.apache.org/CXF20DOC/writing-a-service-with-spring.html
  
  스프링과 아파치 CXF를 이용해 POJO 웹 서비스를 디자인하고 구현하기 : https://www.ibm.com/developerworks/kr/library/ws-pojo-springcxf2/
  
  
• Jersey : sun, CDDL+GPL license, JAX-RS1.1지원
  tutorial : http://blogs.sun.com/enterprisetechtips/entry/jersey_and_spring
   http://www.javakaffee.de/blog/2008/04/21/jersey-spring-integration-mostly-complete/

jsr311-api 1.0 API : https://jsr311.dev.java.net/nonav/releases/1.0/index.html

또한 참고 : http://blog.iolo.pe.kr/449 GAE에서 잘 돌아가지 않는 것이 많은듯 합니다.ㅡㅡ;;

참고로 Restlet보면 안드로이드에서 동작한다고 나와있는데 자세히 안봐서 어떤 내용인지는 모르겠군요. 확인해 보시죠.