Question

Is it possible to set up a JAX-RS application using annotations only? (using Servlet 3.0 and JAX-RS Jersey 1.1.0)

I tried and had no luck. Using some web.xml seems required.

---

Configuration A (working, but has web.xml configuration)

web.xml

   ...
   <servlet>
      <servlet-name>org.foo.rest.MyApplication</servlet-name>
   </servlet>
   <servlet-mapping>
       <servlet-name>org.foo.rest.MyApplication</servlet-name>
       <url-pattern>/*</url-pattern>
   </servlet-mapping>
   ...

Java

@ApplicationPath("/")
public class MyApplication extends Application {
    ...
}

---

Configuration B (not working, exception thrown)

@ApplicationPath("/")
@WebServlet("/*") // <-- 
public class MyApplication extends Application {
    ...
}

The latter seems to insist that the Application will be a subclass of Servlet (the exception leaves no guesswork)

java.lang.ClassCastException: org.foo.rest.MyApplication cannot be cast to javax.servlet.Servlet

---

Questions

1. Why the web.xml definition worked but the annotation didn’t? What’s the difference?

2. Is there a way to have it worked, e.g. have a JAX-RS Application with no web.xml?

Answer 1

It seems that all I needed to do is this (Servlet 3.0 and above)

import javax.ws.rs.ApplicationPath;
import javax.ws.rs.core.Application;

@ApplicationPath("/*")
public class MyApplication extends Application {
    ...
}

And no web.xml configuration was apparently needed (tried on Tomcat 7)