协议缓冲区MIME问题 [英] Protocol Buffers MIME problem

问题描述

帮助！
尝试通过Rest（Jersey）实现Protocol Buffers，但得到此异常。

Help! Trying to implement Protocol Buffers via Rest (Jersey), but get this exception.

class com.util.ProtobufMessageBodyReader
class com.util.ProtobufMessageBodyWriter
Jul 6, 2010 3:43:37 PM org.apache.coyote.http11.Http11Protocol start
INFO: Starting Coyote HTTP/1.1 on http-9102
Jul 6, 2010 3:43:37 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 45485 ms
Jul 6, 2010 3:49:00 PM org.apache.catalina.connector.CoyoteAdapter convertURI
SEVERE: Invalid URI encoding; using HTTP default
Jul 6, 2010 3:49:00 PM com.sun.jersey.spi.container.ContainerRequest getEntity
SEVERE: A message body reader for Java type, class com.example.tutorial.ProfileRequestProto$ProfileRequest, and MIME media type, application/x-protobuf, was not found

我加载了ProtobufMessageBodyReader Apache ContextLoader中的/ Writer。
从上面的日志中，似乎Tomcat找到了这个类，但它显然在读取时失败了

I loaded ProtobufMessageBodyReader/Writer in the Apache ContextLoader. From the log above, it seems Tomcat found the class but it apparent it fails when it reads

 @Consumes("application/x-protobuf")

这是ProtobufMessageBodyReader

Here is ProtobufMessageBodyReader

@Provider
 @Component
 @Consumes("application/x-protobuf")
    public class ProtobufMessageBodyReader implements MessageBodyReader<Message> {

     public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
         return Message.class.isAssignableFrom(type);
     }

     public Message readFrom(Class<Message> type, Type genericType, Annotation[] annotations,
                 MediaType mediaType, MultivaluedMap<String, String> httpHeaders, 
                 InputStream entityStream) throws IOException, WebApplicationException {
         try {
             Method newBuilder = type.getMethod("newBuilder");
             GeneratedMessage.Builder<?> builder = (GeneratedMessage.Builder<?>) newBuilder.invoke(type);
             return builder.mergeFrom(entityStream).build();
         } catch (Exception e) {
             throw new WebApplicationException(e);
         }
     }

  @Override
  public boolean isReadable(Class<?> arg0, Type arg1, Annotation[] arg2) {
   // TODO Auto-generated method stub
   return false;
  }

这里是ProtobufMessageBodyWriter

And here is ProtobufMessageBodyWriter

@Provider
 @Component
 @Produces("application/x-protobuf")
 public class ProtobufMessageBodyWriter implements MessageBodyWriter<Message> {

     public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
         return Message.class.isAssignableFrom(type);
     }

     public long getSize(Message m, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
      return m.getSerializedSize();
     }

     public void writeTo(Message m, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType, MultivaluedMap<String,Object> httpHeaders,OutputStream entityStream) throws IOException, WebApplicationException {
         entityStream.write(m.toByteArray());
     }

以下是来自客户的代码：

Here is the code from client :

URL url = new URL(URL);
   HttpURLConnection http = (HttpURLConnection)url.openConnection();
   http.setDoInput(true);
   http.setDoOutput(true);
   http.setUseCaches(false);  
         http.setRequestMethod("POST");
         http.setRequestProperty("Content-Type","application/x-protobuf");
         http.setRequestProperty("Accept", "application/x-protobuf");

         DataOutputStream stream = new DataOutputStream(http.getOutputStream ());

         if(contentType.equals("application/x-protobuf")) {
          ProfileRequest.Builder profile = ProfileRequest.newBuilder();
          profile.setName("John");
          profile.setId("123");
          profile.build().writeTo(http.getOutputStream());
         }

         stream.flush();
         stream.close();

这是来自服务器的代码

 @POST
    @Consumes("application/x-protobuf")
     public byte[] processProtoRequest(ProfileRequest protoRequest) {

     byte[] result = null;     
     ProfileRequest.Builder profile = ProfileRequest.newBuilder();
     profile.mergeFrom(protoRequest);                  
     result  = getProfileProtoResponse(profile); 

        }catch(Exception e){
         }

        return result;
    }

我无法弄清问题是什么。
Jersey配置有什么吗？或者当我通过HTTP发送协议请求时出了什么问题？

I cannot figure out what is the problem. Is there anything with Jersey config? Or something is wrong when I sent protocol request via HTTP?

任何帮助都会很感激。

谢谢

推荐答案

你自己已经考虑过这个问题了：

You mostly nailed the issue yourself already I think:

和MIME媒体类型，application / x-protobuf，未找到

[...]

and MIME media type, application/x-protobuf, was not found
[...]

从上面的日志中看来，似乎Tomcat找到了这个类，但是当它读取
@Consumes（application / x-protobuf）

From the log above, it seems Tomcat found the class but it apparent it fails when it reads @Consumes("application/x-protobuf")

泽西岛（或者更确切地说是 JSR-311 / JAX-RS ）开箱即用的定义在类MediaType 。要解决您的问题，为 application / x-protobuf 定义适当的媒体类型可能就足够了，请参阅thread [Jersey] MediaType-s？有关此问题的讨论和示例。

The media types supported by Jersey (or rather JSR-311/JAX-RS) out of the box are defined in class MediaType. To resolve your issue it might be enough to define an appropriate media type for application/x-protobuf, see thread [Jersey] MediaType-s? for a discussion and samples regarding this.

这篇关于协议缓冲区MIME问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！