Jersey 2.14: how to receive and parse multipart mime using custom MessageBodyReader

Question

I am not generally used to programming in Java, and this is my first post so I ask for a bit of patience. I am having trouble putting the pieces together for a standalone client that will request via GET and then receive, multipart messages from a server. I should note that I have no way of changing the format of these messages.

The received protocol header looks something like this:

HTTP/1.1 200 OK
Content-type: multipart/custom; boundary=custom-17940605525230162027
X-Custom-Domain-Name: my-custom-domain
Server: Myserver
Content-Length: 71576
Connection: Keep-Alive
Keep-Alive: timeout=5

The received body has the custom boundary element indicated above and is formatted as follows (content mostly elided):

--custom-17940605525230162027
X-Custom-Designation: ack
Content-Type: application/xml
Content-Length: 291

<cust:ack>
A bunch of xml...
</cust:ack>

--custom-17940605525230162027
X-Custom-Designation: update
Content-Type: application/xml
Content-Length: 1101

<cust:update>
A bunch more xml...
</cust:update>

--custom-17940605525230162027
X-Custom-Designation: document
Content-Type: application/xml
Content-Length: 6259

<?xml version="1.0" encoding="UTF-8"?>
Lots more xml...

--custom-17940605525230162027
...

The following code will correctly grab the above content from the server (please ignore extraneous libraries for the moment):

package com.mycompany.multipart.test;

import java.io.IOException;

import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Invocation;
import javax.ws.rs.client.WebTarget;
import javax.ws.rs.core.Configuration;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.core.Response;

import org.glassfish.jersey.client.authentication.HttpAuthenticationFeature;
import org.glassfish.jersey.media.multipart.MultiPart;
import org.glassfish.jersey.media.multipart.MultiPartFeature;


public class ClientMultipartTest {

    public static void main(String[] args) {

        Client client = ClientBuilder.newClient();
        HttpAuthenticationFeature feature = HttpAuthenticationFeature.basic("user1", "password1");
        WebTarget webTarget = client.target("http://theserver:80/test.xqy")
                .queryParam("domain", "12345")
                .queryParam("target", "67890");
        webTarget.register(feature);
        Invocation.Builder invocationBuilder = webTarget.request("multipart/mixed");
        Response response = invocationBuilder.get();
        System.out.println(response.getStatus());
        System.out.println(response.readEntity(String.class));      
    }
}

But I can't quite figure out how to actually pull out the entity as a multipart object. When I try the following code (starting right after webTarget.register()):

MultiPart response = webTarget.request("multipart/mixed").get(MultiPart.class);

I get the following exception:

Dec 22, 2014 10:56:15 PM org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor aroundReadFrom
SEVERE: MessageBodyReader not found for media type=multipart/custom; boundary=custom-17940605525230162027, type=class org.glassfish.jersey.media.multipart.MultiPart, genericType=class org.glassfish.jersey.media.multipart.MultiPart.
Exception in thread "main" org.glassfish.jersey.message.internal.MessageBodyProviderNotFoundException: MessageBodyReader not found for media type=multipart/custom; boundary=custom-17940605525230162027, type=class org.glassfish.jersey.media.multipart.MultiPart, genericType=class org.glassfish.jersey.media.multipart.MultiPart.
    at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.aroundReadFrom(ReaderInterceptorExecutor.java:225)
    at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor.proceed(ReaderInterceptorExecutor.java:149)
    at org.glassfish.jersey.message.internal.MessageBodyFactory.readFrom(MessageBodyFactory.java:1124)
    at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:851)
    at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:783)
    at org.glassfish.jersey.client.ClientResponse.readEntity(ClientResponse.java:326)
    at org.glassfish.jersey.client.JerseyInvocation.translate(JerseyInvocation.java:761)
    at org.glassfish.jersey.client.JerseyInvocation.access$500(JerseyInvocation.java:90)
    at org.glassfish.jersey.client.JerseyInvocation$2.call(JerseyInvocation.java:671)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:228)
    at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:424)
    at org.glassfish.jersey.client.JerseyInvocation.invoke(JerseyInvocation.java:667)
    at org.glassfish.jersey.client.JerseyInvocation$Builder.method(JerseyInvocation.java:396)
    at org.glassfish.jersey.client.JerseyInvocation$Builder.get(JerseyInvocation.java:296)
    at com.mycompany.multipart.test.ClientMultipartTest.main(ClientMultipartTest.java:29)

I think I understand that I need to create and "register" a class that implements a custom MessageBodyReader interface (as seen here). That example is confusing to me however.

Would someone be able to guide me so that I can get to the point of having a MultiPart object whose body parts can be parsed? I also ultimately need to be able to construct a multipart response consisting of only the <cust:ack> elements and post it back to the server.

Many thanks in advance for any help that can be rendered!

@peeskillet I did not do that in the code above, and I'm pretty sure I will need to once I get past this exception. But I'm also pretty sure that it's not the cause of this exception. — Hallmarc, Dec 25 '14 at 08:31
I have registered the MultiPartFeature and still get the same exception. I have even tried to implement my own MessageBodyReader class that @consumes multipart/custom and still get the same exception. I'm completely stumped. — Hallmarc, Dec 29 '14 at 09:56

score 0 · Answer 1 · answered Oct 02 '19 at 21:32

Better late than ever. What you're looking for is this:

MultiPart content = response.readEntity(MultiPart.class);

This will cause the Jersey framework to parse out the content and give you a MultiPart object through which you can iterate over the parts.

Jersey 2.14: how to receive and parse multipart mime using custom MessageBodyReader

1 Answers1