You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@commons.apache.org by "Sergey Vladimirov (JIRA)" <ji...@apache.org> on 2010/06/01 10:30:40 UTC
[jira] Commented: (DBCP-335) NPE with MySQL PreparedStatement
[ https://issues.apache.org/jira/browse/DBCP-335?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12873920#action_12873920 ]
Sergey Vladimirov commented on DBCP-335:
----------------------------------------
Marcus,
In your example code DBCP is not used. If you have exceptions with provided example - it is not DBCP related.
Anyway, if you need to periodicaly check if connection alive, it much better to use DBCP to do so. In fact, DBCP already has properties to check if connection alive:
validationQuery - query used to validate connection
testWhileIdle - set to true to check connection while they are in the pool
timeBetweenEvictionRunsMillis - time between checks (and evictions)
And one more thing about example. Personally i believe (IMHO) it is not correct to call Statement.execute() without synchronization.
> NPE with MySQL PreparedStatement
> --------------------------------
>
> Key: DBCP-335
> URL: https://issues.apache.org/jira/browse/DBCP-335
> Project: Commons Dbcp
> Issue Type: Bug
> Affects Versions: 1.4
> Environment: CloudFoundry, Linux, Sun Java 1.6.0_04, Grails 1.2.2, MySQL Connector 5.1.12
> Reporter: Marcus Better
>
> My Grails application using MySQL and DBCP often throws an exception as below. I can trigger it by making a simultaneous requests (three at a time) on differend threads in a ThreadPoolExecutor. The requests would all use the same query. This triggers the exception with a few percent probability.
> I have tried with DBCP 1.2.2 and 1.4.
> There is a similar-looking [MySQL bug|http://bugs.mysql.com/bug.php?id=41628] but they blame the pool...
> {code}
> Exception in thread "pool-1-thread-12" java.lang.NullPointerException
> at com.mysql.jdbc.PreparedStatement.fillSendPacket(PreparedStatement.java:2475)
> at com.mysql.jdbc.PreparedStatement.fillSendPacket(PreparedStatement.java:2451)
> at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2205)
> at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:96)
> at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:96)
> at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
> at org.hibernate.loader.Loader.getResultSet(Loader.java:1808)
> at org.hibernate.loader.Loader.doQuery(Loader.java:697)
> at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259)
> at org.hibernate.loader.Loader.loadEntity(Loader.java:1881)
> at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:71)
> at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:65)
> at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3072)
> at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:434)
> at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:415)
> at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:165)
> at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:121)
> at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:905)
> at org.hibernate.impl.SessionImpl.immediateLoad(SessionImpl.java:863)
> at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:95)
> at org.codehaus.groovy.grails.orm.hibernate.proxy.HibernateProxyHandler.unwrapProxy(HibernateProxyHandler.java:80)
> at org.codehaus.groovy.grails.orm.hibernate.cfg.GrailsHibernateUtil.unwrapProxy(GrailsHibernateUtil.java:322)
> at org.codehaus.groovy.grails.orm.hibernate.cfg.GrailsHibernateUtil$unwrapProxy.call(Unknown Source)
> at org.codehaus.groovy.grails.plugins.orm.hibernate.HibernatePluginSupport$__clinit__closure88.doCall(HibernatePluginSupport.groovy:401)
> at sun.reflect.GeneratedMethodAccessor381.invoke(Unknown Source)
> at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
> at java.lang.reflect.Method.invoke(Method.java:597)
> at org.codehaus.groovy.runtime.callsite.PogoMetaMethodSite$PogoCachedMethodSiteNoUnwrapNoCoerce.invoke(PogoMetaMethodSite.java:266)
> at org.codehaus.groovy.runtime.callsite.PogoMetaMethodSite.callCurrent(PogoMetaMethodSite.java:51)
> at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:151)
> at org.codehaus.groovy.grails.plugins.orm.hibernate.HibernatePluginSupport$__clinit__closure88.call(HibernatePluginSupport.groovy)
> at sun.reflect.GeneratedMethodAccessor380.invoke(Unknown Source)
> at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
> at java.lang.reflect.Method.invoke(Method.java:597)
> at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:86)
> at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:234)
> at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1049)
> at groovy.lang.ExpandoMetaClass.invokeMethod(ExpandoMetaClass.java:923)
> at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:880)
> at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:924)
> at groovy.lang.ExpandoMetaClass.invokeMethod(ExpandoMetaClass.java:923)
> at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:880)
> at org.codehaus.groovy.runtime.InvokerHelper.invokePogoMethod(InvokerHelper.java:739)
> at org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:722)
> at org.codehaus.groovy.runtime.metaclass.ClosureMetaMethod$1.invoke(ClosureMetaMethod.java:135)
> at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:234)
> at groovy.lang.MetaClassImpl.getProperty(MetaClassImpl.java:1594)
> at groovy.lang.ExpandoMetaClass.getProperty(ExpandoMetaClass.java:951)
> at groovy.lang.MetaClassImpl.getProperty(MetaClassImpl.java:3287)
> at groovy.lang.ExpandoMetaClass.getProperty(ExpandoMetaClass.java:964)
> at org.codehaus.groovy.runtime.callsite.PogoMetaClassGetPropertySite.getProperty(PogoMetaClassGetPropertySite.java:48)
> at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callGroovyObjectGetProperty(AbstractCallSite.java:241)
> at org.example.MyService.onApplicationEvent(MyService.groovy:52)
> at org.example.MyService.onApplicationEvent(MyService.groovy)
> at org.springframework.context.event.SimpleApplicationEventMulticaster$1.run(SimpleApplicationEventMulticaster.java:92)
> at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885)
> at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
> at java.lang.Thread.run(Thread.java:619)
> {code}
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.