Question

I have a webservice which return this kind of json object :

{

"dossiers": [
    {
        "id": "2"
    },
    {
        "id": "3"
    }
]
}

So I’m try to unserialize this answer in a POJO using jersey-client (v1.12).

So here is my current code :

DossiersPOJO.java

 @XmlRootElement( name = "dossiers" )
public class DossiersPOJO
{
    private List<DossierPOJO> dossiers;

    public List<DossierPOJO> getDossiers( )
    {
        return dossiers;
    }

    public void setDossiers( List<DossierPOJO> dossiers )
    {
        this.dossiers = dossiers;
    }
}

Dossier.java

public class DossierPOJO
{
    private Long id;

    public Long getId( )
    {
        return id;
    }

    public void setId( Long id )
    {
        this.id = id;
    }
}

And the client code itself :

WebResource siraWebResource = Client.create( ).resource(
                "http://localhost:8081/site/rest/path/resources" );

Builder accept = siraWebResource.accept( MediaType.APPLICATION_JSON_TYPE );
//        accept.accept( "application/json" );

DossiersPOJO dossierJson = accept.get( DossiersPOJO.class );

But when I call get I get this error stack :

log4j:WARN No appenders could be found for logger (org.springframework.core.env.StandardEnvironment).
log4j:WARN Please initialize the log4j system properly.
26 avr. 2012 17:18:03 com.sun.jersey.api.client.ClientResponse getEntity
GRAVE: A message body reader for Java class fr.paris.lutece.batches.ramen.bean.DossiersPOJO, and Java type class fr.paris.lutece.batches.ramen.bean.DossiersPOJO, and MIME media type application/json was not found
26 avr. 2012 17:18:03 com.sun.jersey.api.client.ClientResponse getEntity
GRAVE: 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.MimeMultipartProvider
  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.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

I can’t figure out where the problem come from since I know my client POJO are exactly similar to server side one.

Answer 1

Actually it was easier than I thought!
In the first time my pom.xml contains only one dependency :

<dependency>
    <groupId>com.sun.jersey</groupId>
    <artifactId>jersey-client</artifactId>
    <version>1.12</version>
</dependency>

And I found out that json to object conversion needs another dependency :

<dependency>
    <groupId>com.sun.jersey</groupId>
    <artifactId>jersey-json</artifactId>
    <version>1.12</version>
</dependency>

And that it, adding this dependency is enought and now my project is able to handle json response and convert it to pojo object.