Unable to get collection response from cxf rest web service - web-services

Question

I am trying to get java.util.List as response from cxf rest web service.
I have tried with WebClient class's method postObjectGetCollection method but no luck.
I am getting - org.apache.cxf.jaxrs.client.ClientWebApplicationException: .No message body reader has been found for class : interface java.util.Collection, ContentType : application/json.
Below are my client code-
String mediaType = "application/json";
if (url != null) {
List<DataTypeDTO> resultdtos = new ArrayList<DataTypeDTO>();
WebClient client = WebClient.create(url);
client = client.accept(mediaType).type(mediaType).path(uri);
resultdtos = (List<DataTypeDTO>)client.getCollection(DataTypeDTO.class);
System.out.println(resultdtos);
}
Please help me out if i am missing any configuration or other things.

Answer 1

You need to provide the provider list while creating the webClient object in your rest client.
You can use the below code to resolve your issue:
final String url = "http://localhost:10227/someService";
final String uri = "/manageXyz/fetchAllDataTypes";
final String mediaType = "application/json";
Object response = null;
List<Object> providers = new ArrayList<Object>();
providers.add( new JacksonJaxbJsonProvider() );
WebClient client = WebClient.create(url, providers);
client = client.accept(mediaType).type(mediaType).path(uri);
response = (List<Object>)client.post(oemUser, List.class);
If you are using maven, you also need to provide below required jars to resolve maven dependency in your project:
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-jaxrs</artifactId>
<version>1.5.4</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-xc</artifactId>
<version>1.9.13</version>
</dependency>