NPE in QueryMapper when use Query with null as value

[EGD]

Spring Data MongoDB version: 3.1.5

used Query annotation:

@Query("parentId: null")
AnyEntity findRootScope();

used entity class:

    @Id
    public String id;
    public String name;
    @Field(targetType = FieldType.OBJECT_ID)
    public String parentId;
}

when calling this method i get NullPointerException:

java.lang.NullPointerException
at org.springframework.data.mongodb.core.convert.QueryMapper.applyFieldTargetTypeHintToValue(QueryMapper.java:692)
at org.springframework.data.mongodb.core.convert.QueryMapper.getMappedValue(QueryMapper.java:335)
at org.springframework.data.mongodb.core.convert.QueryMapper.getMappedObjectForField(QueryMapper.java:240)
at org.springframework.data.mongodb.core.convert.QueryMapper.getMappedObject(QueryMapper.java:143)
at org.springframework.data.mongodb.core.QueryOperations$QueryContext.getMappedQuery(QueryOperations.java:255)
at org.springframework.data.mongodb.core.MongoTemplate.doFind(MongoTemplate.java:2542)
at org.springframework.data.mongodb.core.ExecutableFindOperationSupport$ExecutableFindSupport.doFind(ExecutableFindOperationSupport.java:220)
at org.springframework.data.mongodb.core.ExecutableFindOperationSupport$ExecutableFindSupport.oneValue(ExecutableFindOperationSupport.java:132)
at org.springframework.data.mongodb.repository.query.AbstractMongoQuery.lambda$getExecution$4(AbstractMongoQuery.java:159)
at org.springframework.data.mongodb.repository.query.AbstractMongoQuery.doExecute(AbstractMongoQuery.java:132)
at org.springframework.data.mongodb.repository.query.AbstractMongoQuery.execute(AbstractMongoQuery.java:107)
at org.springframework.data.repository.core.support.RepositoryMethodInvoker.doInvoke(RepositoryMethodInvoker.java:137)
at org.springframework.data.repository.core.support.RepositoryMethodInvoker.invoke(RepositoryMethodInvoker.java:121)
at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.doInvoke(QueryExecutorMethodInterceptor.java:152)
at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.invoke(QueryExecutorMethodInterceptor.java:131)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:215)
at com.sun.proxy.$Proxy44.findRootScope(Unknown Source)

[christophstrobl]

Thanks for reporting - well look into it.
Meanwhile, have you tried { parentId : { $exists: false } } or is an equality filter required here?

[EGD]

Thanks, in my particular case, replacing to $exists works.

[rogeriomgatto]

Another workaround is to use new BsonNull() instead of null. This also works for setting null values in update dsl, which triggers the same bug.