How to get full REST request body using Jersey?

Question

How can one get the full HTTP REST request body for a POST request using Jersey?

In our case the data will be XML. Size would vary from 1K to 1MB.

The docs seem to indicate you should use MessageBodyReader but I can't see any examples.

Answer 1

You could use the @Consumes annotation to get the full body:

import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.MediaType;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;

@Path("doc")
public class BodyResource
{
  @POST
  @Consumes(MediaType.APPLICATION_XML)
  public void post(Document doc) throws TransformerConfigurationException, TransformerException
  {
    Transformer tf = TransformerFactory.newInstance().newTransformer();
    tf.transform(new DOMSource(doc), new StreamResult(System.out));
  }
}

Note: Don't forget the "Content-Type: application/xml" header by the request.

Answer 2

Try this using this single code:

import javax.ws.rs.POST;
import javax.ws.rs.Path;

@Path("/serviceX")
public class MyClassRESTService {

    @POST
    @Path("/doSomething")   
    public void someMethod(String x) {

        System.out.println(x);
                // String x contains the body, you can process
                // it, parse it using JAXB and so on ...

    }
}

The url for try rest services ends .... /serviceX/doSomething

Answer 3

Turns out you don't have to do much at all.

See below - the parameter x will contain the full HTTP body (which is XML in our case).

@POST
public Response go(String x) throws IOException {
    ...
}

Answer 4

It does seem you would have to use a MessageBodyReader here. Here's an example, using jdom:

import org.jdom.Document;
import javax.ws.rs.ext.MessageBodyReader;
import javax.ws.rs.ext.Provider;
import javax.ws.rs.ext.MediaType;
import javax.ws.rs.ext.MultivaluedMap;
import java.lang.reflect.Type;
import java.lang.annotation.Annotation;
import java.io.InputStream;

@Provider // this annotation is necessary!
@ConsumeMime("application/xml") // this is a hint to the system to only consume xml mime types
public class XMLMessageBodyReader implements MessageBodyReader<Document> {
  private SAXBuilder builder = new SAXBuilder();

  public boolean isReadable(Class type, Type genericType, Annotation[] annotations, MediaType mediaType) {
    // check if we're requesting a jdom Document
    return Document.class.isAssignableFrom(type);
  }

  public Document readFrom(Class type, Type genericType, Annotation[] annotations, MediaType mediaType, MultivaluedMap<String, String> httpHeaders, InputStream entityStream) {
    try {
      return builder.build(entityStream);
    }
    catch (Exception e) {
      // handle error somehow
    }
  } 
}

Add this class to the list of resources your jersey deployment will process (usually configured via web.xml, I think). You can then use this reader in one of your regular resource classes like this:

@Path("/somepath") @POST
public void handleXMLData(Document doc) {
  // do something with the document
}

I haven't verified that this works exactly as typed, but that's the gist of it. More reading here:

• http://weblogs.java.net/blog/mhadley/archive/2008/02/integrating_jer_2.html
• http://blogs.oracle.com/sandoz/entry/jersey_and_abdera_with_a

Answer 5

Since you're transferring data in xml, you could also (un)marshal directly from/to pojos.

There's an example (and more info) in the jersey user guide, which I copy here:

POJO with JAXB annotations:

@XmlRootElement
public class Planet {
    public int id;
    public String name;
    public double radius;
}

Resource:

@Path("planet")
public class Resource {

    @GET
    @Produces(MediaType.APPLICATION_XML)
    public Planet getPlanet() {
        Planet p = new Planet();
        p.id = 1;
        p.name = "Earth";
        p.radius = 1.0;

        return p;
    }

    @POST
    @Consumes(MediaType.APPLICATION_XML)
    public void setPlanet(Planet p) {
        System.out.println("setPlanet " + p.name);
    }

}      

The xml that gets produced/consumed:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<planet>
    <id>1</id>
    <name>Earth</name>
    <radius>1.0</radius>
</planet>