Spring Data findFirstByOrderBy NullPointerException

Drivers & Stacks Spring Data Neo4j & Neo4j-OGM
1

I attempted to implement as follows:

Page<NetworkElement> findFirstByOrderByCaptureIdDesc(Pageable pageable);

captureId is a column name, ie. member variable of NetworkElement.

When I attempt to start the Spring Boot application I get:

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'neRepository': Invocation of init method failed; nested exception is java.lang.NullPointerException
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1778)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:593)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515)
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
	at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1247)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1167)
	at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:857)
	at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:760)
	... 33 common frames omitted
Caused by: java.lang.NullPointerException: null
	at org.springframework.data.neo4j.repository.query.TemplatedQueryCreator.complete(TemplatedQueryCreator.java:60)
	at org.springframework.data.neo4j.repository.query.TemplatedQueryCreator.complete(TemplatedQueryCreator.java:32)
	at org.springframework.data.repository.query.parser.AbstractQueryCreator.createQuery(AbstractQueryCreator.java:95)
	at org.springframework.data.repository.query.parser.AbstractQueryCreator.createQuery(AbstractQueryCreator.java:81)
	at org.springframework.data.neo4j.repository.query.PartTreeNeo4jQuery.<init>(PartTreeNeo4jQuery.java:56)
	at org.springframework.data.neo4j.repository.query.GraphQueryLookupStrategy.resolveQuery(GraphQueryLookupStrategy.java:89)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lookupQuery(RepositoryFactorySupport.java:566)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$mapMethodsToQuery$1(RepositoryFactorySupport.java:559)
	at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
	at java.util.Iterator.forEachRemaining(Iterator.java:116)
	at java.util.Collections$UnmodifiableCollection$1.forEachRemaining(Collections.java:1049)
	at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801)
	at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
	at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.mapMethodsToQuery(RepositoryFactorySupport.java:561)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$new$0(RepositoryFactorySupport.java:551)
	at java.util.Optional.map(Optional.java:215)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.<init>(RepositoryFactorySupport.java:551)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:324)
	at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.lambda$afterPropertiesSet$5(RepositoryFactoryBeanSupport.java:297)
	at org.springframework.data.util.Lazy.getNullable(Lazy.java:211)
	at org.springframework.data.util.Lazy.get(Lazy.java:94)
	at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:300)
	at org.springframework.data.neo4j.repository.support.Neo4jRepositoryFactoryBean.afterPropertiesSet(Neo4jRepositoryFactoryBean.java:75)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1837)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1774)
	... 44 common frames omitted
2

I can reproduce the problem you are facing. In the current 5.2 RC it is only partial solved because there will also be multiple results instead of one (for findFirst without any amount).
So basically we could patch 5.1 to not throw an exception but the behaviour might not be satisfying.
We need to discuss and compare with the other Spring Data projects which is the stronger component: the keyword findFirst (for 1) or the parameter Pageable with a size of 2, for example.
I created a ticker for findFirst[n] support in the SDN Jira for this.

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