NPE in PersistentPropertyResourceMapping.isExported using SD MongoDB @DbRef Object [DATAREST-796]

Mark Paluch opened DATAREST-796 and commented

Spring Data Rest with Spring Data MongoDB runs into a NPE when using DbRef on Object properties in the associated class.

Model:

    @Data
    @NoArgsConstructor
    @Document(collection = "model")
    public static class Model {

        @Id
        private ObjectId id;
        private String name;

        @DBRef
        private Set<Post> posts;
    }

    @Data
    @NoArgsConstructor
    @Document(collection = "post")
    public static class Post {

        @Id
        private ObjectId id;

        @DBRef
        private Object owner;
    }

Stack-trace:

java.lang.NullPointerException: null
	at org.springframework.data.rest.core.mapping.PersistentPropertyResourceMapping.isExported(PersistentPropertyResourceMapping.java:84) ~[spring-data-rest-core-2.4.4.RELEASE.jar:na]
	at org.springframework.data.rest.core.mapping.MappingResourceMetadata.isExported(MappingResourceMetadata.java:77) ~[spring-data-rest-core-2.4.4.RELEASE.jar:na]
	at org.springframework.data.rest.webmvc.mapping.AssociationLinks.isLinkableAssociation(AssociationLinks.java:95) ~[spring-data-rest-webmvc-2.4.4.RELEASE.jar:na]
	at org.springframework.data.rest.webmvc.json.PersistentEntityJackson2Module$AssociationUriResolvingDeserializerModifier.updateBuilder(PersistentEntityJackson2Module.java:339) ~[spring-data-rest-webmvc-2.4.4.RELEASE.jar:na]
	at com.fasterxml.jackson.databind.deser.BeanDeserializerFactory.buildBeanDeserializer(BeanDeserializerFactory.java:240) ~[jackson-databind-2.6.5.jar:2.6.5]

Affects: 2.4.4 (Gosling SR4), 2.5 RC1 (Hopper)

Reference URL: https://gist.github.com/mp911de/1edbc0ad7b3ae621cc491ac6f2f2e100

Issue Links:

• DATAREST-797 NPE in LinkCollectingAssociationHandler.doWithAssociation using SD MongoDB @DbRef Object