java - NPE 将数据保存到 neo4j 时

Question

我正在使用 spring-boot 1.5.1 和 spring-boot-starter-data-neo4j

我的 neo4j 配置如下:

@SpringBootApplication // same as @Configuration @EnableAutoConfiguration
                        // @ComponentScan
@EnableNeo4jRepositories(basePackages = "org.nymeria.umapi.spring.neo4j")
@EnableTransactionManagement
public class Application {

    public static void main(String[] args) throws InterruptedException {
        SpringApplication.run(Application.class, args);
    }

}

在一个名为org.nymeria.umapi.spring.neo4j.movi​​es的包中，我里面有一个电影模型/存储库/ Controller 包，它工作得很好。

我创建了另一个名为 org.nymeria.umapi.spring.neo4j.tvshow 的包，其中包含存储库/模型包，但保存数据不起作用。

我的 TvShow 模型类如下所示:

@NodeEntity
public class TvShow {
    @GraphId
    private Long tvshow_id;
    @Property
    EnumClass genre;
    @Index(unique = true)
    @Property(name = "imdb_ud")
    String imdbID;
    @Property
    List<SimplePojo> property = new ArrayList<>();

    public TvShow () {
        super();
    }
    // getter and setter ...
}

然后我有简单的界面TvShowRepository，当我执行tvshowRepo.save(tvshow);它抛出一个 NPE 异常

java.lang.NullPointerException
    at org.neo4j.ogm.compiler.builders.node.DefaultNodeBuilder.addProperty(DefaultNodeBuilder.java:45)
    at org.neo4j.ogm.context.EntityGraphMapper.updateNode(EntityGraphMapper.java:249)
    at org.neo4j.ogm.context.EntityGraphMapper.mapEntity(EntityGraphMapper.java:220)
    at org.neo4j.ogm.context.EntityGraphMapper.map(EntityGraphMapper.java:135)
    at org.neo4j.ogm.session.delegates.SaveDelegate.save(SaveDelegate.java:83)
    at org.neo4j.ogm.session.delegates.SaveDelegate.save(SaveDelegate.java:44)
    at org.neo4j.ogm.session.Neo4jSession.save(Neo4jSession.java:447)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.springframework.data.neo4j.transaction.SharedSessionCreator$SharedSessionInvocationHandler.invoke(SharedSessionCreator.java:131)
    at com.sun.proxy.$Proxy80.save(Unknown Source)
    at org.springframework.data.neo4j.repository.support.SimpleNeo4jRepository.save(SimpleNeo4jRepository.java:76)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:504)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:489)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:461)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:61)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:282)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:57)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
    at com.sun.proxy.$Proxy97.save(Unknown Source)
    at org.nymeria.umapi.spring.movie.feeder.utils.TvShowFactory.createTvShow(TvShowFactory.java:56)
    at org.nymeria.umapi.spring.movie.feeder.utils.TvShowFactoryService.getOrCreateTvShow(TvShowFactoryService.java:17)
    at org.nymeria.umapi.spring.movie.feeder.utils.TvShowFactoryServiceTest.storeInDatabase(TvShowFactoryServiceTest.java:60)
    at org.nymeria.umapi.spring.movie.feeder.utils.TvShowFactoryServiceTest.test(TvShowFactoryServiceTest.java:48)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
    at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
    at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:252)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)

我不知道这是配置错误还是我做错了什么或者是错误

Answer 1

这个问题很可能

  @Property
  List<SimplePojo> property = new ArrayList<>();

节点不能将嵌套对象作为属性。

(即便如此，NullPointerException 也没有帮助 - 请打开一个问题以在 https://github.com/neo4j/neo4j-ogm/issues 抛出更有用的错误)