Amdatu + Jackson - Not Serializing ArrayList - RESTful Service with OSGi

Question

I am writing a Hello World web-service, and got stuck trying to serialize/deserialize the class list returned.

I have this code that is supposed to return a list of Conferences in Json:

@GET
@Produces({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
@Description("lists conferences")
public List<Conference> list() {
    return agenda.listConferences();
}

Now, when I test the Service then I get this as response:

SEVERE: The system could not find a javax.ws.rs.ext.MessageBodyWriter or a DataSourceProvider class for the java.util.ArrayList type and application/json mediaT
ype.  Ensure that a javax.ws.rs.ext.MessageBodyWriter exists in the JAX-RS application for the type and media type specified.
Nov 16, 2013 2:49:00 PM org.apache.wink.server.internal.RequestProcessor logException
INFO: The following error occurred during the invocation of the handlers chain: WebApplicationException (500 - Internal Server Error) with message 'null' while
processing GET request sent to http://localhost:8080/conferences

If I return the class Conference it works and returns the respective Json of the class, but if I make it return a list of conferences then it throws this exception.

I am using these bundles to manage the RESTful service:

  <dependency>
      <groupId>org.codehaus.jackson</groupId>
      <artifactId>jackson-jaxrs</artifactId>
      <version>1.9.13</version>
  </dependency>
  <dependency>
      <groupId>org.codehaus.jackson</groupId>
      <artifactId>jackson-core-asl</artifactId>
      <version>1.9.13</version>
  </dependency>
  <dependency>
      <groupId>org.codehaus.jackson</groupId>
      <artifactId>jackson-mapper-asl</artifactId>
      <version>1.9.13</version>
  </dependency>
  <dependency>
      <groupId>org.amdatu.web</groupId>
      <artifactId>org.amdatu.web.rest.wink</artifactId>
      <version>1.0.1</version>
  </dependency>
  <dependency>
      <groupId>org.amdatu.web</groupId>
      <artifactId>org.amdatu.web.rest.jaxrs</artifactId>
      <version>1.0.0</version>
  </dependency>

Anybody knows why?

Answer 1

The reason is that you are using an old version of Amdatu Wink. The current version is 1.0.6. Jackson support was not available yet in the version you are using.