Question

我正在使用Neo4j 2.2.1和Spring Data Neo4j 4.0.0，我正在尝试导入类似时间树的图形（具有下一个，第一个，最后一个和子关系），但只有2个级别。我保存在根对象，我得到以下异常（由于巨大的大小，我省略了异常中的大部分重复部分）：

org.neo4j.ogm.session.result.ResultProcessingException: Failed to execute request: {"statements":[{"statement":"CREATE (_1:`Trace`{_1_props}), 
...
...
        at org.neo4j.ogm.session.request.DefaultRequest.execute(DefaultRequest.java:90)
        at org.neo4j.ogm.session.request.SessionRequestHandler.execute(SessionRequestHandler.java:94)
        at org.neo4j.ogm.session.delegates.SaveDelegate.save(SaveDelegate.java:66)
        at org.neo4j.ogm.session.Neo4jSession.save(Neo4jSession.java:375)
        at org.springframework.data.neo4j.repository.GraphRepositoryImpl.save(GraphRepositoryImpl.java:101)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:452)
        at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:437)
        at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:409)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
        at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
        at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
        at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
        at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
        at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
        at com.sun.proxy.$Proxy42.save(Unknown Source)
        at de.rwthaachen.service.core.EpisodeServiceImpl.loadEpisodeVersionDataTest(EpisodeServiceImpl.java:141)
        at sampleapp.EpisodeLauncher.main(EpisodeLauncher.java:70)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
    Caused by: org.apache.http.client.HttpResponseException: Server Error
        at org.neo4j.ogm.session.request.DefaultRequest.execute(DefaultRequest.java:77)
        ... 27 more

这是我插入数据的函数：

public void loadEpisodeVersionDataTest(String projectName, Long timestampOfEpisodeVersion, LinkedHashSet<ExecutionRecord> executionRecords)
    {
        Long episodeNodeId = timeTreeService.getEpisodeVersionNodeId(projectName, timestampOfEpisodeVersion);
        EpisodeVersion episodeVersion = episodeVersionRepository.findOne(episodeNodeId);

        if(episodeVersion.getTraces() == null)
        {
            episodeVersion.contains(new LinkedHashSet<Trace>());
            Trace firstTrace = new Trace(0);
            episodeVersion.addTrace(firstTrace);
            episodeVersion.first(firstTrace);
            episodeVersion.last(firstTrace);
        }

        HashMap<String, Filter> filterMatchingStringToFilterMap = new HashMap<String, Filter>();
        for(Filter filter : filterRepository.getFiltersByFilterVersionChangeId(episodeVersion.getFilterVersionChange().getId()))
        {
            filterMatchingStringToFilterMap.put(filter.getMatchingString(), filter);
        }

        Iterator<ExecutionRecord> executionRecordIterator = executionRecords.iterator();
        ExecutionRecord previousExecutionRecord = episodeVersion.getLastTrace().getLastExecutionRecord();
        while(executionRecordIterator.hasNext())
        {
            ExecutionRecord executionRecord = executionRecordIterator.next();

            executionRecord.callerMappedOn(filterMatchingStringToFilterMap.get(executionRecord.getCallerFilterMatchingString()));
            executionRecord.calleeMappedOn(filterMatchingStringToFilterMap.get(executionRecord.getCalleeFilterMatchingString()));

            if(executionRecord.getTraceSequenceNumber() != episodeVersion.getLastTrace().getTraceSequenceNumber())
            {
                Trace newTrace = new Trace(executionRecord.getTraceSequenceNumber());
                newTrace.nextOf(episodeVersion.getLastTrace());
                episodeVersion.addTrace(newTrace);
                episodeVersion.last(newTrace);
            }

            if(episodeVersion.getLastTrace().getExecutionRecords() == null)
            {
                episodeVersion.getLastTrace().contains(new LinkedHashSet<ExecutionRecord>());
                episodeVersion.getLastTrace().first(executionRecord);
            }

            episodeVersion.getLastTrace().addExecutionRecord(executionRecord);
            executionRecord.nextOf(previousExecutionRecord);
            previousExecutionRecord = executionRecord;
            episodeVersion.getLastTrace().last(executionRecord);
        }

        episodeVersionRepository.save(episodeVersion);
    }

这个例外是什么意思？当我调试我的代码时，对象定义是按预期的。提前谢谢你的建议真的很感激！

修改

所以，我设法使之前的异常消失了。但现在我得到了另一个例外，如下所示。

java.lang.OutOfMemoryError: Java heap space\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:366)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.matchers.MemoMismatchesMatcher.match(MemoMismatchesMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.ZeroOrMoreMatcher.match(ZeroOrMoreMatcher.java:39)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.ZeroOrMoreMatcher.match(ZeroOrMoreMatcher.java:39)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.parserunners.BasicParseRunner.run(BasicParseRunner.java:72)\r\n\tat org.parboiled.parserunners.ReportingParseRunner.runBasicMatch(ReportingParseRunner.java:86)\r\n\tat org.parboiled.parserunners.ReportingParseRunner.run(ReportingParseRunner.java:66)\r\n\tat org.parboiled.scala.parserunners.ReportingParseRunner.run(ReportingParseRunner.scala:34)\r\n\tat org.neo4j.cypher.internal.compiler.v2_2.parser.Base$class.parseOrThrow(Base.scala:117)\r\n\tat org.neo4j.cypher.internal.compiler.v2_2.parser.CypherParser.parseOrThrow(CypherParser.scala:27)\r\n\tat org.neo4j.cypher.internal.compiler.v2_2.parser.CypherParser.parse(CypherParser.scala:34)\r\n\tat org.neo4j.cypher.internal.compiler.v2_2.CypherCompiler.prepareQuery(CypherCompiler.scala:126)\r\n\tat org.neo4j.cypher.internal.compatibility.CompatibilityFor2_2$$anon$2$$anonfun$3.apply(CompatibilityFor2_2.scala:154)\r\n\tat org.neo4j.cypher.internal.compatibility.CompatibilityFor2_2$$anon$2$$anonfun$3.apply(CompatibilityFor2_2.scala:154)\r\n\tat scala.util.Try$.apply(Try.scala:161)\r\n\tat org.neo4j.cypher.internal.compatibility.CompatibilityFor2_2$$anon$2.<init>(CompatibilityFor2_2.scala:154)\r\n\tat org.neo4j.cypher.internal.compatibility.CompatibilityFor2_2$class.produceParsedQuery(CompatibilityFor2_2.scala:153)\r\n\tat org.neo4j.cypher.internal.compatibility.CompatibilityFor2_2Cost.produceParsedQuery(CompatibilityFor2_2.scala:326)\r\n\tat org.neo4j.cypher.internal.CypherCompiler.parseQuery(CypherCompiler.scala:81)\r\n\tat org.neo4j.cypher.ExecutionEngine$$anonfun$org$neo4j$cypher$ExecutionEngine$$parsePreParsedQuery$1.apply(ExecutionEngine.scala:116)\r\n\tat org.neo4j.cypher.ExecutionEngine$$anonfun$org$neo4j$cypher$ExecutionEngine$$parsePreParsedQuery$1.apply(ExecutionEngine.scala:116)\r\n\tat org.neo4j.cypher.internal.LRUCache.getOrElseUpdate(LRUCache.scala:34)\r\n\tat org.neo4j.cypher.ExecutionEngine.org$neo4j$cypher$ExecutionEngine$$parsePreParsedQuery(ExecutionEngine.scala:116)\r\n\tat org.neo4j.cypher.ExecutionEngine.parseQuery(ExecutionEngine.scala:112)\r\n\tat org.neo4j.cypher.internal.ServerExecutionEngine.isPeriodicCommit(ServerExecutionEngine.scala:34)\r\n\tat org.neo4j.cypher.javacompat.internal.ServerExecutionEngine.isPeriodicCommit(ServerExecutionEngine.java:72)\r\n\tat org.neo4j.server.rest.transactional.TransactionHandle.selectExecutionStrategy(TransactionHandle.java:189)\r\n\tat org.neo4j.server.rest.transactional.TransactionHandle.commit(TransactionHandle.java:133)\r\n\tat org.neo4j.server.rest.web.TransactionalService$2.write(TransactionalService.java:211)\r\n\tat com.sun.jersey.core.impl.provider.entity.StreamingOutputProvider.writeTo(StreamingOutputProvider.java:71)\r\n\tat com.sun.jersey.core.impl.provider.entity.StreamingOutputProvider.writeTo(StreamingOutputProvider.java:57)\r\n\tat com.sun.jersey.spi.container.ContainerResponse.write(ContainerResponse.java:302)\r\n\tat com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1510)\r\n\tat com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1419)\r\n\tat com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1409)\r\n\tat com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:409)\r\n\tat com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:540)\r\n\tat com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:715)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:790)\r\n\tat org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:800)\r\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1669)\r\n\tat org.neo4j.server.rest.dbms.AuthorizationFilter.doFilter(AuthorizationFilter.java:120)\r\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)\r\n\tat org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)\r\n\tat org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:221)\r\n\tat org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1125)\r\n\tat org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)\r\n\tat org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)\r\n\tat org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1059)\r\n\tat org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)\r\n\tat org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:52)\r\n\tat org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)\r\n\tat org.eclipse.jetty.server.Server.handle(Server.java:497)\r\n\tat org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310)\r\n\tat org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:248)\r\n\tat org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)\r\n\tat org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:620)\r\n\tat org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:540)\r\n\tat java.lang.Thread.run(Thread.java:745)\r\nCaused by: java.lang.OutOfMemoryError: Java heap space\r\n\tat java.util.HashMap.resize(HashMap.java:580)\r\n\tat java.util.HashMap.addEntry(HashMap.java:879)\r\n\tat java.util.HashMap.put(HashMap.java:505)\r\n\tat java.util.HashSet.add(HashSet.java:217)\r\n\tat org.parboiled.MatcherContext.memoizeMismatch(MatcherContext.java:312)\r\n\tat org.parboiled.matchers.MemoMismatchesMatcher.match(MemoMismatchesMatcher.java:44)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.matchers.MemoMismatchesMatcher.match(MemoMismatchesMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.FirstOfMatcher.match(FirstOfMatcher.java:41)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n\tat org.parboiled.MatcherContext.runMatcher(MatcherContext.java:351)\r\n\tat org.parboiled.matchers.SequenceMatcher.match(SequenceMatcher.java:46)\r\n\tat org.parboiled.parserunners.BasicParseRunner.match(BasicParseRunner.java:77)\r\n"}]}
    at org.neo4j.ogm.session.response.JsonResponse.parseErrors(JsonResponse.java:132)
    at org.neo4j.ogm.session.response.JsonResponse.parseColumns(JsonResponse.java:109)
    at org.neo4j.ogm.session.response.JsonResponse.initialiseScan(JsonResponse.java:53)
    at org.neo4j.ogm.session.response.RowModelResponse.initialiseScan(RowModelResponse.java:60)
    at org.neo4j.ogm.session.response.RowModelResponse.<init>(RowModelResponse.java:34)
    at org.neo4j.ogm.session.response.SessionResponseHandler.updateObjects(SessionResponseHandler.java:77)
    at org.neo4j.ogm.session.delegates.SaveDelegate.save(SaveDelegate.java:67)
    at org.neo4j.ogm.session.delegates.SaveDelegate.save(SaveDelegate.java:41)
    at org.neo4j.ogm.session.Neo4jSession.save(Neo4jSession.java:370)
    at org.springframework.data.neo4j.repository.GraphRepositoryImpl.save(GraphRepositoryImpl.java:46)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:452)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:437)
    at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:409)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
    at com.sun.proxy.$Proxy42.save(Unknown Source)
    at de.rwthaachen.service.core.EpisodeServiceImpl.loadEpisodeVersionDataTest(EpisodeServiceImpl.java:141148)
    at sampleapp.EpisodeLauncher.main(EpisodeLauncher.java:70)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)
Caused by: org.apache.http.client.HttpResponseException: Server Error
    at org.neo4j.ogm.session.request.DefaultRequest.execute(DefaultRequest.java:77)
    ... 27 more

Answer 1

SDN 4并非真正用于将对象批量导入Neo4j。它是用于通用Java应用程序的对象图映射框架，而不是批量导入程序（它将自己特定的一组问题带到表中）。支持SDN预期用例的一些设计决策与您尝试设计专用ETL时所做的相反。我们也受到Neo4j的HTTP Transactional端点的性能的限制，虽然绝对的速度绝不慢，但不能希望与批量插入器竞争。

我们将来会对性能进行一些改进，当Neo4j的新二进制协议发布时（2.3），我们将把它作为我们的传输协议插入。我们希望这可以提高进出数据库的传输速度至少一个数量级。但是，请不要期望这些更改能够从根本上改变SDN 4的行为特征。虽然未来版本可能能够以比目前更快的速度加载几千个节点，但它仍然不会成为ETL工具，我不希望它被这样使用。

Answer 2

如果你受到记忆的限制，那么定期保存会有所帮助，因为SDN 4会持续发生变化。您看到的多个提交是一个正在运行的事务的一部分。

在LinkedHashSet问题上，使用像这样的接口Set

 Set<Foo> x = new LinkedHashSet<();
 ...
 public Set<Foo> getX() {}

应该有用。

Answer 3

经过几个小时的反复试验，我发现我需要限制我的保存深度。

之前，我没有指定深度级别，并且保存的对象越来越大，因为其子项的插入也同时运行。因此，在每个save方法的深度为1之后，我终于摆脱了StackOverFlow错误。并且，通过不定期保存（我将所有对象放在ArrayList中并将它们全部保存在最后），导入ca的性能提升1分钟。 1000个节点（有关系）。

尽管如此，性能仍然不尽如人意，因为我可以在不到1分钟的时间内使用我以前的MongoDB实现导入超过60,000个数据。我不知道是不是因为SDN4，以及嵌入式API是否会更快。如果有人对SDN4和嵌入式API进行任何基准测试，我真的很好奇。

SDN4 - ResultProcessingException：无法执行请求

修改

3 个答案: