JAX-RS - 找不到类型的响应对象的MessageBodyWriter

我试图在JBoss 7.2 Rest Easy中找出JAX-RS的样本 . 我收到如下错误信息 .

SEVERE [org.jboss.resteasy.core.SynchronousDispatcher]（http- / 0.0.0.0:80-2）执行GET / test / resources / 1失败：org.jboss.resteasy.core.NoMessageBodyWriterFoundFailure：找不到MessageBodyWriter for类型的响应对象：vsample.Image of media type：image / jpeg at org.jboss.resteasy.core.ServerResponse.writeTo（ServerResponse.java:216）[resteasy-jaxrs-2.3.5.Final.jar：] at org .jboss.resteasy.core.SynchronousDispatcher.writeJaxrsResponse（SynchronousDispatcher.java:602）[resteasy-jaxrs-2.3.5.Final.jar：] at org.jboss.resteasy.core.SynchronousDispatcher.invoke（SynchronousDispatcher.java:528） [resteasy-jaxrs-2.3.5.Final.jar：] org.jboss.resteasy.core.SynchronousDispatcher.invoke（SynchronousDispatcher.java:126）[resteasy-jaxrs-2.3.5.Final.jar：] at org . jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service（ServletContainerDispatcher.java:208）[resteasy-jaxrs-2.3.5.Final.jar：] at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service （HttpServle tDispatcher.java:55）[resteasy-jaxrs-2.3.5.Final.jar：] org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service（HttpServletDispatcher.java:50）[resteasy-jaxrs-2.3 . 5.Final.jar：]在org的javax.servlet.http.HttpServlet.service（HttpServlet.java:847）[jboss-servlet-api_3.0_spec-1.0.2.Final.jar：1.0.2.Final] . apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:295）[jbossweb-7.2.0.Final.jar：7.2.0.Final] at org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java： 214）[jbossweb-7.2.0.Final.jar：7.2.0.Final] at org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:230)[jbossweb-7.2.0.Final.jar:7.2 .O.Final]在org.apache.atb上的org.apache.catalina.core.StandardContextValve.invoke（StandardContextValve.java:149）[jbossweb-7.2.0.Final.jar：7.2.0.Final] . 在组织的security.SecurityContextAssociationValve.invoke（SecurityContextAssociationValve.java:169）[jboss-as-web-7.2.0.Final.jar：7.2.0.Final] . apache.catalina.core.StandardHostValve.invoke（StandardHostValve.java:145）[jbossweb-7.2.0.Final.jar：7.2.0.Final] at org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java： 97）[jbossweb-7.2.0.Final.jar：7.2.0.Final] org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve.java:102)[jbossweb-7.2.0.Final.jar:7.2 .O.Final]在org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:336）[jbossweb-7.2.0.Final.jar：7.2.0.Final] org.apache.coyote.http11 . Http11Processor.process（Http11Processor.java:856）[jbossweb-7.2.0.Final.jar：7.2.0.Final] at org.apache.coyote.http11.Http11Protocol $ Http11ConnectionHandler.process（Http11Protocol.java:653)[jbossweb -7.2.0.Final.jar:7.2.0.Final] at org.apache.tomcat.util.net.JIoEndpoint $ Worker.run（JIoEndpoint.java:920）[jbossweb-7.2.0.Final.jar：7.2 java.lang.Thread.run中的.0.Final]（Thread.java:722）[rt.jar：1.7.0_17]

我的代码是，

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


     @ApplicationPath("/rest")
   public class Etag extends Application {
    }

和，

import java.util.Date;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.PathParam;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.Request;
import javax.ws.rs.core.CacheControl;
import javax.ws.rs.core.EntityTag;
import javax.ws.rs.core.Response.ResponseBuilder;


@Path( "/test" )
public class EtagImpl {

   @GET
   @Produces("image/jpeg")

   @Path("resources/{id}")
      public Response getImage(@PathParam("id") String id, @Context Request request) {

       ImageDAOImpl imageDAO = new ImageDAOImpl();

        Image image = imageDAO.getImage(id);
       CacheControl cc = new CacheControl();
       cc.setMaxAge(172800); // 2 days
       Response.ResponseBuilder rb = null;
       String lastModified = image.getDateModified().toString();
     //  EntityTag etag = new EntityTag(imageDAO.getImage(id).hashCode()+"");
       EntityTag etag = new EntityTag(lastModified.hashCode()+"");
       System.out.println("Writing Response:" + etag);
       rb = request.evaluatePreconditions(etag);
       if (rb != null) 
       {
           return rb.cacheControl(cc).tag(etag).build();
       }

       //If rb is null then either it is first time request; or resource is modified
       //Get the updated representation and return with Etag attached to it
               rb = Response.ok(imageDAO.getImage(id)).cacheControl(cc).tag(etag);
               return rb.build();
    }

由于我是RestEasy的新手，因此有必要让想法朝着正确的方向前进

谢谢和问候，拉姆 .