REST WS with Interface

Question

I'm trying to implement a REST WS. The following code works ok:

@Path("/MyRest")
@WebService
public class MyService {
    @GET
    @Produces(MediaType.APPLICATION_JSON)
    @Path("/{id}")
    public Response test(@PathParam("id") String id) {
        String str = "{\"status\":\"ok\",\"id\":\"" + id + "\"}";
        return Response.status(200).entity(str).build();
    }
}

web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>WSRest</display-name>
<servlet>
  <servlet-name>Jersey REST Service</servlet-name>
<servlet-class>
  com.sun.jersey.spi.container.servlet.ServletContainer
</servlet-class>
  <init-param>
    <param-name>com.sun.jersey.config.property.packages</param-name>
    <param-value>test</param-value>
  </init-param>
  <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
  <servlet-name>Jersey REST Service</servlet-name>
  <url-pattern>/rest/*</url-pattern>
</servlet-mapping>
</web-app>

Now i'm trying to do it with an Interface. The interface would be like follows, I guess:

@Path("/MyRest")
@WebService
public interface IService {
    @GET
    @Produces(MediaType.APPLICATION_JSON)
    @Path("/{id}")
    public Response test(@PathParam("id") String id);
}

And now the WS implementation would be like this, right?:

public class MyService implements IService{
@Override
public Response test(@PathParam("id") String id) {
    String str = "{\"status\":\"ok\",\"id\":\"" + id + "\"}";
    return Response.status(200).entity(str).build();
}
}

I'm getting " HTTP Status 500 - Servlet.init() for servlet Jersey REST Service threw exception " when I try to "run" it again :/ Any ideas? Thanks in advance.

Full exception:

type Exception report

message Servlet.init() for servlet Jersey REST Service threw exception

description The server encountered an internal error that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Servlet.init() for servlet Jersey REST Service threw exception
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
    org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2430)
    org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2419)
    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    java.lang.Thread.run(Thread.java:722)
root cause

com.sun.jersey.spi.inject.Errors$ErrorMessagesException
    com.sun.jersey.spi.inject.Errors.processErrorMessages(Errors.java:170)
    com.sun.jersey.spi.inject.Errors.postProcess(Errors.java:136)
    com.sun.jersey.spi.inject.Errors.processWithErrors(Errors.java:199)
    com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:795)
    com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:790)
    com.sun.jersey.spi.container.servlet.ServletContainer.initiate(ServletContainer.java:491)
    com.sun.jersey.spi.container.servlet.ServletContainer$InternalWebComponent.initiate(ServletContainer.java:321)
    com.sun.jersey.spi.container.servlet.WebComponent.load(WebComponent.java:605)
    com.sun.jersey.spi.container.servlet.WebComponent.init(WebComponent.java:207)
    com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:376)
    com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:559)
    javax.servlet.GenericServlet.init(GenericServlet.java:160)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
    org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
    org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2430)
    org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2419)
    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    java.lang.Thread.run(Thread.java:722)

Answer 1

An example of a web method using an interface:

Web service implementation:

@Path("/WS")
@WebService
public class WebService implements IWebService {

@Override
@POST
@Consumes("application/json")
@Produces("application/json")
@Path("/Login")
public Response Login(JSONObject data) {
    //stuff here
}
}

Interface:

public interface IWebService {

@POST
@Consumes("application/json")
@Produces("application/json")
@Path("/Login")
public Response Login(JSONObject data);

}