Integration testing of a REST API - retrieve utilities

RetrieveUtils.java

public static String retrieveJsonFromResponse( final HttpResponse response ) 
      throws IOException{
   Preconditions.checkNotNull( response );
   
   return IOUtils.toString( response.getEntity().getContent() );
}

public static < T >T retrieveResourceFromResponse
      ( final HttpResponse response, final Class< T > clazz ) throws IOException{
   Preconditions.checkNotNull( response );
   Preconditions.checkNotNull( clazz );
   
   final String jsonFromResponse = retrieveJsonFromResponse( response );
   return ConvertUtil.convertJsonToResource( jsonFromResponse, clazz );
}

This gist is used in:
http://www.baeldung.com/2011/10/13/integration-testing-a-rest-api/