How to Consume Facebook JSON using Jersey Client

Question

My code is not working:

package com.foo.json;

import javax.xml.bind.annotation.XmlRootElement;

import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.WebResource;

@XmlRootElement
public class Me {

    public String id;
    public String name;

    public static void main(String[] args) {
        Client client = Client.create();
        WebResource web_resource = client.resource("https://graph.facebook.com/me?fields=id,name&access_token=deleted");
        Me response = web_resource.get(Me.class);
        System.out.println(response);
    }

}

The error is:

Mar 28, 2012 11:56:43 AM com.sun.jersey.api.client.ClientResponse getEntity
SEVERE: A message body reader for Java class com.foo.json.Me, and Java type class com.foo.json.Me, and MIME media type text/javascript; charset=UTF-8 was not found
Mar 28, 2012 11:56:43 AM com.sun.jersey.api.client.ClientResponse getEntity
SEVERE: The registered message body readers compatible with the MIME media type are:
*/* ->
  com.sun.jersey.core.impl.provider.entity.FormProvider
  com.sun.jersey.core.impl.provider.entity.StringProvider
  com.sun.jersey.core.impl.provider.entity.ByteArrayProvider
  com.sun.jersey.core.impl.provider.entity.FileProvider
  com.sun.jersey.core.impl.provider.entity.InputStreamProvider
  com.sun.jersey.core.impl.provider.entity.DataSourceProvider
  com.sun.jersey.core.impl.provider.entity.XMLJAXBElementProvider$General
  com.sun.jersey.core.impl.provider.entity.ReaderProvider
  com.sun.jersey.core.impl.provider.entity.DocumentProvider
  com.sun.jersey.core.impl.provider.entity.SourceProvider$StreamSourceReader
  com.sun.jersey.core.impl.provider.entity.SourceProvider$SAXSourceReader
  com.sun.jersey.core.impl.provider.entity.SourceProvider$DOMSourceReader
  com.sun.jersey.json.impl.provider.entity.JSONJAXBElementProvider$General
  com.sun.jersey.json.impl.provider.entity.JSONArrayProvider$General
  com.sun.jersey.json.impl.provider.entity.JSONObjectProvider$General
  com.sun.jersey.core.impl.provider.entity.XMLRootElementProvider$General
  com.sun.jersey.core.impl.provider.entity.XMLListElementProvider$General
  com.sun.jersey.core.impl.provider.entity.XMLRootObjectProvider$General
  com.sun.jersey.core.impl.provider.entity.EntityHolderReader
  com.sun.jersey.json.impl.provider.entity.JSONRootElementProvider$General
  com.sun.jersey.json.impl.provider.entity.JSONListElementProvider$General
  com.sun.jersey.json.impl.provider.entity.JacksonProviderProxy

Exception in thread "main" com.sun.jersey.api.client.ClientHandlerException: A message body reader for Java class com.foo.json.Me, and Java type class com.foo.json.Me, and MIME media type text/javascript; charset=UTF-8 was not found
    at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:550)
    at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:506)
    at com.sun.jersey.api.client.WebResource.handle(WebResource.java:684)
    at com.sun.jersey.api.client.WebResource.get(WebResource.java:191)
    at com.foo.json.Me.main(Me.java:18)

The response from curl-ing the URL is:

$ curl --head https://graph.facebook.com/me?fields=id,name\&access_token=deleted
HTTP/1.1 200 OK
Access-Control-Allow-Origin: *
Cache-Control: private, no-cache, no-store, must-revalidate
Content-Type: text/javascript; charset=UTF-8
Expires: Sat, 01 Jan 2000 00:00:00 GMT
Pragma: no-cache
X-FB-Rev: 532491
X-FB-Debug: EGBmGLM1xfMiWi8KILCkQaG6FTn+WnRufgVY7FXDxnQ=
X-Cnection: close
Content-Length: 0
Date: Wed, 28 Mar 2012 18:58:53 GMT

and the content is:

$curl --head https://graph.facebook.com/me?fields=id,name\&access_token=deleted
{"id":"100001234567890","name":"My Name"}

What am I doing wrong? I do want to use the Jersey Client library and would prefer not to have to switch to another library. Thanks!

just letting you know that you can manually award the bounty http://stackoverflow.com/faq#bounty incase you are already satisfied with the accepted answer. helps to clear this question from the featured(questions with bounties) tab. — bool.dev, Apr 07 '12 at 20:57

score 7 · Accepted Answer · answered Apr 03 '12 at 19:33

You just have to mention Accept header of the response to application/json as it is coming as json. In absence of it, it is treated as text/javascript response(check headers of your curl response) which is giving you ClientHandlerException.

Running code:

TestClient.java

public class TestClient {

    public static void main(String[] args) {

        Client client = Client.create();
        WebResource web_resource = client.resource("https://graph.facebook.com/me?fields=id,name&access_token=deleted");
        MyBean response=web_resource.accept(MediaType.APPLICATION_JSON).get(MyBean.class);
        System.out.println(response.getId());
    }

}

MyBean.java

@XmlRootElement
public class MyBean{

    String id;
    String name;

    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

score 1 · Answer 2 · answered Mar 29 '12 at 13:11

1

Try to change your ME class to following:

@XmlElement
public String id;
@XmlElement
public String name;

And add proper getters and setters for them(!). In addition I'd suggest you to move main() method to other class.

answered Mar 29 '12 at 13:11

Alex Stybaev

4,623
3
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Hi, Thank you for your comments, but it did not work. The problem is that I am trying to consume JSON (not XML). I have included the jersey-json dependency/jars but I am not properly configuring it to scan my Me.java class and generate an appropriate message body reader (I think). – necromancer Mar 29 '12 at 17:46
Adding the following lines works but it is ugly because I am unmarshalling it once as String from web_resource and then unmarshalling it again via a separate JSON context. I am sure there is a better way, and I hope somebody can point me to it. ` JSONJAXBContext json_jaxb_context = new JSONJAXBContext(Me.class); String response = web_resource.get(String.class); Me me = json_jaxb_context.createJSONUnmarshaller().unmarshalFromJSON(new StringReader(response), Me.class);` – necromancer Mar 29 '12 at 17:48

How to Consume Facebook JSON using Jersey Client

2 Answers2