我正在尝试在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:不能 找到类型的响应对象的MessageBodyWriter:vsample.Image of 媒体类型: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:] at 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(HttpServletDispatcher.java:55) [resteasy-jaxrs-2.3.5.Final.jar:] at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:50) [resteasy-jaxrs-2.3.5.Final.jar:] at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) [jboss-servlet-api_3.0_spec-1.0.2.Final.jar:1.0.2.Final] at org.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:7.2.0.Final] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:149) [jbossweb-7.2.0.Final.jar:7.2.0.Final] at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:169) [jboss-as-web-7.2.0.Final.jar:7.2.0.Final] at org.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] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:102) [jbossweb-7.2.0.Final.jar:7.2.0.Final] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:336) [jbossweb-7.2.0.Final.jar:7.2.0.Final] at 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:7.2.0.Final] at java.lang.Thread.run(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,因此让想法朝着正确的方向前进是有帮助的
谢谢和问候, 拉姆。
答案 0 :(得分:11)
这只是意味着RestEasy不知道如何将Image对象“转换”为@Produces注释中指定的mediatype(“image / jpeg”)。
默认情况下,只有有限的受支持类型列表,resteasy可以自动编组和解组:
最简单的方法是让Response填充图像的字节数组表示。
Response.ok(imageDAO.getImage(id).getBytes()).cacheControl(cc).tag(etag);
另一种选择是编写自己的MessageBodyWriter来处理这种转换。 有关详细信息http://docs.jboss.org/resteasy/docs/3.0.5.Final/userguide/html/Content_Marshalling_Providers.html
,请查看resteasy文档