Deploying Jersey in Tomcat 6.0

Jersey is a reference implementation for the JAX-RS (JSR-311) for building RESTful Web services. It is nearing approval with the JSR committees. While there are many wikis and articles in using Jersey with Netbeans (downloading the Netbeans 6.1 EE package includes everything you need for JSR-311), there was very little information on using Tomcat 6.0 with Jersey. After piecing together several blogs, I was able to get a simple resource working in Tomcat using JSR-311.

The following are the steps I used to get this working:

1. Download and unjar the Jersey distribution (I used 0.8) from https://jersey.dev.java.net/ to a location on your system (lets call it JERSEY_HOME for this article).
2. Download and install the Java-WS distribution (I used 2.1) from https://jax-ws.dev.java.net/. (lets call it JAXWS_HOME for this article).
3. Rama Pulavarthi wrote a blog (in fact the key for me) in configuring tomcat to reference the Jersey distribution jars. To summarize, in TOMCAT_HOME/conf/catalina.properties modify the shared.loader property entry to point to your JAXWS_HOME/lib/*.jar. Mine looks like this:

   
      shared.loader=C:/dev/jaxws-ri/lib/*.jar
   
   

4. Create a new Dynamic Web Project in Eclipse using Tomcat 6.0 as the application server.
5. Create a new library in which you add the following JARs:
   1. JERSEY_HOME/lib/asm-3.1.jar
   2. JERSEY_HOME/lib/jersey.jar
   3. JERSEY_HOME/lib/jsr311-api.jar
6. Next modify the web.xml to include the adaptor for jersey. Most of the Blogs refer to a different class than what appears in 0.8 I am not certain which is the right class, only the following works for me (and the documented one is not available throught the downloads!):

   
      <servlet>
         <servlet-name>ServletAdaptor</servlet-name>
         <servlet-class>com.sun.jersey.impl.container.servlet.ServletAdaptor</servlet-class>
         <load-on-startup>1</load-on-startup>
      </servlet>
      <servlet-mapping>
         <servlet-name>ServletAdaptor</servlet-name>
         <url-pattern>/resources/*</url-pattern>
      </servlet-mapping>
      <session-config>
         <session-timeout>30</session-timeout>
      </session-config>
   
   

7. If you start Tomcat, you will see the following error:

   
      com.sun.jersey.api.container.ContainerException: The ResourceConfig instance does not contain any root resource classes.
   
   

   This error is due to not providing any root RESTful resources.

8. Create a new class and include the following:

   
   import javax.ws.rs.GET;
   import javax.ws.rs.ProduceMime;
   import javax.ws.rs.Path;
   
   @Path("/test")
   public class TestResource {
   
    @GET
    @ProduceMime("text/html")
    public String getMessage( ) {
     return "hello";
    }
   }
   
   

9. Start and test the application with the following url:

   
      http://localhost:8080/appName/resources/test
   
   

   and you should see a hello in your web-browser.