How to bind request body to action method parameter?

I understand how Play binds URI segments or parameters to action method parameters. I also saw how an uploaded file can be accessed.

But I am still looking for the way to bind the request entity of a PUT or POST request to a method parameter.

Suppose the request is sth like

PUT /blog/entries/67

Content-Type: application/atom+xml

<entry>...</entry>

And I would like to bind that to an entry parameter:

public static void (String entryId, Entry entry) {
    // entryId开发者_JAVA技巧 being 67
    // entry being the deserialized Atom payload (e.g. using Apache Abdera parser)

   backend.updateEntry(67,entry);

   // AtomPub's 'canonical' response is the updated entry.
   render(entry) 

}

Two questions:

Does something like this work?

Where do I find the documentation of how to create the deserializer?

Take a look at the Custom Binding documentation on the Play site.

http://www.playframework.org/documentation/1.2.3/controllers#custombinding

I think what you are looking for is play.data.binding.TypeBinder, which allows you to customise the way Play binds certain objects in your controller.

Update:

Looking at the play groups, Guillaume has posted the following code for handling JSON in the body of a POST, so this could easily be adapted to get XML from an atom+xml input. It uses a BinderPlugin, rather than the TypeBinder, which allows you to do more pwerful binding operations.

package plugins;

import play.*;
import play.mvc.*;

import com.google.gson.*;

import java.util.*;
import java.lang.reflect.*;
import java.lang.annotation.*;

public class BinderPlugin extends PlayPlugin {

    public Object bind(String name, Class clazz, Type type, Annotation[] annotations, Map<String, String[]> params) {
        if(Http.Request.current().contentType.equals("application/json")) {
            JsonObject json = new JsonParser().parse(Scope.Params.current().get("body")).getAsJsonObject();
            if(clazz.equals(String.class)) {
                return json.getAsJsonPrimitive(name).getAsString();
            }
        }
        return null;
    }

}