RESTful web services in Java

Recently, I read some articles about RESTful web services and I am looking for some java libraries which have great support for REST. REST is supported by Axis2. However, the support is very limited. First, document(http://ws.apache.org/axis2/1_3/rest-ws.html) of REST support in the official web site is horrible. The content is very very brief so that I have more questions and confusions than what have been addressed by that document. Support for REST in Axis2 relies on a new feature in WSDL2 which enables HTTP binding. Here is a good article about it:http://www.ibm.com/developerworks/webservices/library/ws-rest1/. However, HTTP binding doesn't enable programmers to implement a full REST style system. I did not dig into WSDL2 to get more knowledge about its HTTP binding. Here(http://wso2.org/blog/footballsoccerpainting/949) is an article from someone else who complains Axis2.
Then, I found that JCP published a Java API specification about RESTful web services. It is JSR-311(http://jcp.org/en/jsr/detail?id=311). That looks pretty good because now we have a standard about how to use REST in Java. Jersey(https://jersey.dev.java.net/) is reference implementation of the specification. Besides Jersey, Restlet(http://www.restlet.org/) is another implementation which provides more features. Note that the specification itself is still in beta phase.

I decided to try Jersey. First download and unpack it.
Sample code:

@Path("/")
public class RESTTest{
    @HttpContext UriInfo uriInfo;	
    
    @GET
    @ProduceMime("text/plain")
    public String getUserAll(){
    	return "You want to retrieve information about all users.";
    }
    
    @Path("{user}")
    public UserResource getUserInfoAsText(@UriParam("user") String userid){
    	return new UserResource(userid);
    }
}

Most readers have noticed that Java annotation is used frequently. I think this method is handy and convenient.