首先，我可能会在这里做一些不必要的事情，但我相信这个问题与此无关。我试图用这个转换器类在neo4j中存储ZonedDateTime值：
public class ZonedDateTimeConverter implements AttributeConverter<ZonedDateTime, Long> {
@Override
public Long toGraphProperty(ZonedDateTime value) {
return value != null ? value.toEpochSecond() : null;
}
@Override
public ZonedDateTime toEntityAttribute(Long value) {
if (value == null) return null;
Instant i = Instant.ofEpochSecond(value);
ZoneId zoneId = ZoneId.systemDefault();
return ZonedDateTime.ofInstant(i, zoneId);
}
}
保存值似乎工作正常，但在检索时（例如使用findOne），我得到以下内容：
org.neo4j.ogm.metadata.MappingException: Error mapping GraphModel to instance of co.sens.data.models.Transaction
at org.neo4j.ogm.mapper.GraphEntityMapper.mapEntities(GraphEntityMapper.java:97)
at org.neo4j.ogm.mapper.GraphEntityMapper.map(GraphEntityMapper.java:69)
at org.neo4j.ogm.session.response.SessionResponseHandler.loadById(SessionResponseHandler.java:149)
at org.neo4j.ogm.session.delegates.LoadOneDelegate.load(LoadOneDelegate.java:45)
at org.neo4j.ogm.session.delegates.LoadOneDelegate.load(LoadOneDelegate.java:36)
at org.neo4j.ogm.session.Neo4jSession.load(Neo4jSession.java:99)
at org.springframework.data.neo4j.repository.GraphRepositoryImpl.findOne(GraphRepositoryImpl.java:60)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:475)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:460)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:432)
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$1.proceedWithInvocation(TransactionInterceptor.java:99)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
at com.sun.proxy.$Proxy112.findOne(Unknown Source)
at co.sens.data.AccountRepositoryTest.testTransactionsForAccount(AccountRepositoryTest.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 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:73)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:82)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:73)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:224)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:83)
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:68)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:163)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:27)
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.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
Caused by: java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Long
at co.sens.data.ZonedDateTimeConverter.toEntityAttribute(ZonedDateTimeConverter.java:13)
at org.neo4j.ogm.entityaccess.FieldWriter.write(FieldWriter.java:64)
at org.neo4j.ogm.mapper.GraphEntityMapper.writeProperty(GraphEntityMapper.java:164)
at org.neo4j.ogm.mapper.GraphEntityMapper.setProperties(GraphEntityMapper.java:129)
at org.neo4j.ogm.mapper.GraphEntityMapper.mapNodes(GraphEntityMapper.java:110)
at org.neo4j.ogm.mapper.GraphEntityMapper.mapEntities(GraphEntityMapper.java:94)
... 62 more
这是一个错误还是我错误地认为它应该如何工作？
答案 0 :(得分：0)
问题是当通过网络返回查询结果时，JSON会丢失类型信息;在这种情况下，数值被解释为整数。
将转换器更改为处理Number应该注意这一点。这是一个例子：https://github.com/neo4j/neo4j-ogm/blob/master/src/main/java/org/neo4j/ogm/typeconversion/DateLongConverter.java