Failed to execute goal org.apache.felix:maven-scr-plugin:1.20.0:scr (generate-scr-scrdescriptor) on project

Hi All,

I am trying to expose some RESTfull webservices on AEM. I have followed the instructions in this http://techagyan.blogspot.in/2015/02/be-restful-on-aem6.html​

I'm getting following error:
"@Component : Service interface information is missing! (org.apache.felix:maven-scr-plugin:1.20.0:scr:generate-scr-scrdescriptor:process-classes)"

and

My Code is:

package com.nextrow.restservice.core;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Service;
@Service
@Component(metatype = false)
@Path("/helloservice")
public class SampleResource {
  @GET
  @Path("/sayhi")
  public String helloWorld() {
  return "SampleResource says hi";
  }
  @GET
  @Path("/getoperation")
  @Produces({ MediaType.TEXT_PLAIN })
  public String getServiceOperation() {
  String status = "false";
  // service.dosomething return
  return status;
  }
}