Estoy tratando de almacenar una colección de guayaba especial para almacenar informes, pero aparece un error cuando se inicia la aplicación Spring.

Este es el error:

 org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'repositoryEntityController' defined in URL [jar:file:/C:/Users/mirel/.m2/repository/org/springframework/data/spring-data-rest-webmvc/2.5.6.RELEASE/spring-data-rest-webmvc-2.5.6.RELEASE.jar!/org/springframework/data/rest/webmvc/RepositoryEntityController.class]: Unsatisfied dependency expressed through constructor parameter 4; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'defaultConversionService' defined in class path resource [org/springframework/data/rest/webmvc/config/RepositoryRestMvcConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.format.support.DefaultFormattingConversionService]: Factory method 'defaultConversionService' threw exception; nested exception is java.lang.NullPointerException

Este es el modelo:

 public class Report { @Id private String id; private Calendar date; private BiMap<String, Multimap<String, String>> data; public Report() { } public Calendar getDate() { return date; } public void setDate(Calendar date) { this.date = date; } public BiMap<String, Multimap<String, String>> getData() { return data; } public void setData(BiMap<String, Multimap<String, String>> data) { this.data = data; } }

Repositorio:

 public interface ReportRepository extends MongoRepository<Report, String>{ }

Creo que defaultConversionService no puede guardar el tipo de datos MultiMap de la biblioteca Guava. ¿Cómo puedo guardar el modelo de informe?