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Posted to ojb-user@db.apache.org by Daniel Perry <d....@netcase.co.uk> on 2004/10/11 16:29:27 UTC
SQLExcpetion
Hi all,
One of our systems has been running fine (live) for the last few weeks until
yesterday when for about half an hour it started randomly crashing. Since
then it has been fine! The (partial) exception trace is below. From what i
can figure the problem is coming from dud mysql connections. However, i
thought that OJB checked the connection before using it by using the
validation query?
I'm using OJB 1.0.0, mysql-connector 3.0.10, and mysql 4.0.18.
Any ideas about what would cause this? Anyway i can prevent it occuring
again?
Thanks,
Daniel.
[org.apache.ojb.broker.accesslayer.StatementsForClassImpl] ERROR: No
operations allowed after connection closed.
Connection was closed due to the following exception:
** BEGIN NESTED EXCEPTION **
java.sql.SQLException
MESSAGE: Communication link failure: java.io.IOException, underlying cause:
Unexpected end of input stream
** BEGIN NESTED EXCEPTION **
java.io.IOException
MESSAGE: Unexpected end of input stream
STACKTRACE:
java.io.IOException: Unexpected end of input stream
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
at
com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1496)
at org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
Source)
at org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unknown
Source)
at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown Source)
at
org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterator(Unknown
Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFromQuery(Unkn
own Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQuery(Unknow
n Source)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQuery(Unknow
n Source)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(
Unknown Source)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(
Unknown Source)
at
org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadData(Unknown
Source)
at org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
Source)
at
org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getData(Unknown
Source)
at
org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.iterator(Unknown
Source)
at
org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForEachIterator
(ForEachSupport.java:329)
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RE: Bug identified (was RE: SQLExcpetion)
Posted by Daniel Perry <d....@netcase.co.uk>.
No problem. I've not come accross many bugs (well serious ones) in OJB, but
it's nice to find a hole and hopefully prevent it causing problems for other
people. I'm just glad it's sorted now, and our clients app isnt crashing
anymore.
I agree with your comments on cleaning up a bit better. The code seems to
do better if transactions are used, but much of my code doesnt have any
requirement for them.
Thanks,
Daniel.
> -----Original Message-----
> From: Armin Waibel [mailto:arminw@apache.org]
> Sent: 16 November 2004 12:53
> To: OJB Users List
> Subject: Re: Bug identified (was RE: SQLExcpetion)
>
>
> Hi Daniel,
>
> many thanks for your detailed description and suggestion.
>
> >
> > The solution is in ConnectionManagerImpl.getConnection method. The
> code is
> > already there, but commented out:
> >
> >> // if (con == null || !isAlive(con))
> >> // isAlive check, how do we react if false and we in tx?
> >> // create a new connection isn't the right way I think.
> >> if (con == null)
> >
> >
> > I think this code should be applied - or at the very least, should be
> > modified and applied if not inside a transaction:
> >
> > if (con == null || (!isInLocalTransaction() && !isAlive(con)) )
> >
>
> I will check in your patch ASAP. Additionally I think we should release
> the closed connection instance and I will do a minor refactoring of
> CollectionProxyDefaultImpl to handle the used PB instance more strict.
>
>
> regards,
> Armin
>
>
> Daniel Perry wrote:
>
> > I believe that I have solved this problem, and that there is a
> bug in OJB.
> > I cannot be sure, but with the fix, the app has been running
> for 10 days now
> > with no reported errors.
> >
> > It seems that in certain circumstances an old connection will
> be reused, and
> > it will not be validated (or checked for being alive).
> >
> > The following conditions are required for the error to occur :
> > 1. An object is cached (it will only happen with a long term cache - eg
> > ObjectCacheDefaultImpl)
> > 2. The object has been cached for long enough for the database
> connection
> > that was used to load it has expired
> > 3. The object was loaded from outside a transaction (or
> possibly also inside
> > a very long living transaction)
> > 4. A collection proxy (not sure if it affects other proxies) is
> materialised
> > from within this
> > object
> >
> > What seems to happen, is the connection which was used to load
> the object is
> > held onto, and when the collection is materialised it reuses this stale
> > connection and crashes out. It might also be caused if it has
> already been
> > materialised and refresh=true - not sure how that works though.
> >
> > This bug will only affect people using OJB in accordance with the above
> > criteria. ObjectCachePerBrokerImpl shouldn't be affected. Also the bug
> > wont apply if using transactions - as when it is closed it drops the
> > connection.
> >
> > The solution is in ConnectionManagerImpl.getConnection method.
> The code is
> > already there, but commented out:
> >
> >> // if (con == null || !isAlive(con))
> >> // isAlive check, how do we react if false and we in tx?
> >> // create a new connection isn't the right way I think.
> >> if (con == null)
> >
> >
> > I think this code should be applied - or at the very least, should be
> > modified and applied if not inside a transaction:
> >
> > if (con == null || (!isInLocalTransaction() && !isAlive(con)) )
> >
> > Daniel.
> >
> >
> >>-----Original Message-----
> >>From: Daniel Perry [mailto:d.perry@netcase.co.uk]
> >>Sent: 02 November 2004 11:14
> >>To: OJB Users List
> >>Subject: RE: SQLExcpetion
> >>
> >>
> >>Once again our app has started getting these errors (see trace
> below). It
> >>seems to be happening after several days of operation.
> >>
> >>The problem always seems to happen when iterating over a proxied
> >>collection
> >>in a jsp (using jakarta JSTL c:forEach tag).
> >>
> >>See comments below:
> >>
> >>
> >>>Is the error always caused by the same class
> >>>
> >>> >>>>at
> >>> >>>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForE
> >>> >>>
> >>> >>>achIterator
> >>>
> >>>or always caused when materialized a proxied collection?
> >>
> >>Yes it's caused by that same class, but not always from the same jsp.
> >>
> >>But it's also always when proxied collections are materialised.
> >>
> >>
> >>>Does the error occur when OJB materialize a class with clob/blob or
> >>>binary/object field?
> >>>
> >>
> >>Dont think so.
> >>
> >>
> >>>>Is there a way for me to clear the connection pool?
> >>>
> >>>You can try
> >>>ConnectionFactoryFactory.createConnectionFactory().releaseAllRe
> sources()
> >>>CFF is a singleton. This call clear the used pool and close all
> >>>connections of the pool (connections in use will be ignored AFAIK)
> >>>
> >>>Or extend ConnectionFactoryPooledImpl and add your own
> >>
> >>monitoring methods.
> >>
> >>
> >>I've tried clearing the connection pool every hour, so the connections
> >>should be fine. I havnt tried clearing the cache...
> >>
> >>How are connections obtained when cached objects have their proxied
> >>collections materialised? (note no transactions are being used)
> >>
> >>I think an object is being loaded, and stuck in the cache.
> Days later the
> >>object is being used and is having a proxied collection
> materialised, and
> >>this is using the origional connection.
> >>
> >>From what i can see in the code, a collection proxy obtains a
> broker, the
> >>broker obtains a connection - but (and i might have got the code
> >>wrong here)
> >>it should reuse the broker it used when it was initally loaded,
> >>and then the
> >>broker reuses the conenction without checking it isnt closed :
> >>ConnectionManagerImpl.getConnection
> >>
> >> // if (con == null || !isAlive(con))
> >> // isAlive check, how do we react if false and we in tx?
> >> // create a new connection isn't the right way I think.
> >> if (con == null)
> >>
> >>This only checks if it has a connection, not if the connection is valid.
> >>Maybe i should reinstate the (con == null || !isAlive(con)) ???
> >>
> >>Could this be the cause of my problem? or am i way off track!
> >>
> >>Daniel.
> >>
> >>Stack trace:
> >>
> >>org.apache.jasper.JasperException:
> >>org.apache.ojb.broker.PersistenceBrokerException:
> >>org.apache.ojb.broker.PersistenceBrokerSQLException:
> >>java.sql.SQLException:
> >>No operations allowed after connection closed.
> >>
> >>Connection was closed due to the following exception:
> >>
> >>** BEGIN NESTED EXCEPTION **
> >>
> >>java.sql.SQLException
> >>MESSAGE: Communication link failure: java.io.IOException,
> >>underlying cause:
> >>Unexpected end of input stream
> >>
> >>** BEGIN NESTED EXCEPTION **
> >>
> >>java.io.IOException
> >>MESSAGE: Unexpected end of input stream
> >>
> >>STACKTRACE:
> >>
> >>java.io.IOException: Unexpected end of input stream
> >> at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
> >> at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
> >> at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
> >> at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
> >> at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
> >> at
> >>com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.
> java:1496)
> >> at
> >>org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
> >>Source)
> >> at
> >>org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unkno
> >>wn Source)
> >> at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown
> >>Source)
> >> at
> >>org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterato
> r(Unknown
> >>Source)
> >> at
> >>org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFrom
> >>Query(Unkn
> >>own Source)
> >> at
> >>org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQu
> >>ery(Unknow
> >>n Source)
> >> at
> >>org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQue
> >>ry(Unknown
> >>Source)
> >> at
> >>org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQue
> >>ry(Unknown
> >>Source)
> >> at
> >>org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQu
> >>ery(Unknow
> >>n Source)
> >> at
> >>org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollecti
> >>onByQuery(
> >>Unknown Source)
> >> at
> >>org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollecti
> >>onByQuery(
> >>Unknown Source)
> >> at
> >>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadDa
> >>ta(Unknown
> >>Source)
> >> at
> >>org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
> >>Source)
> >> at
> >>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getDat
> >>a(Unknown
> >>Source)
> >> at
> >>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.iterat
> >>or(Unknown
> >>Source)
> >> at
> >>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForEa
> >>chIterator
> >>(ForEachSupport.java:329)
> >> at
> >>org.apache.taglibs.standard.tag.common.core.ForEachSupport.support
> >>edTypeForE
> >>achIterator(ForEachSupport.java:205)
> >> at
> >>org.apache.taglibs.standard.tag.common.core.ForEachSupport.prepare
> >>(ForEachSu
> >>pport.java:137)
> >> at
> >>javax.servlet.jsp.jstl.core.LoopTagSupport.doStartTag(LoopTagSuppo
> >>rt.java:22
> >>7)
> >> at
> >>org.apache.jsp.WEB_002dINF.jsps.manager.behavioursscreen.appraisal
> >>_jsp._jspx
> >>_meth_c_forEach_0(appraisal_jsp.java:294)
> >> at
> >>org.apache.jsp.WEB_002dINF.jsps.manager.behavioursscreen.appraisal
> >>_jsp._jspS
> >>ervice(appraisal_jsp.java:186)
> >> at
> >>org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
> >> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
> >> at
> >>org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrap
> >>per.java:2
> >>98)
> >> at
> >>org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
> >> at
> >>org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
> >> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
> >> at
> >>org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(A
> >>pplication
> >>FilterChain.java:237)
> >> at
> >>org.apache.catalina.core.ApplicationFilterChain.doFilter(Applicati
> >>onFilterCh
> >>ain.java:157)
> >> at
> >>org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationD
> >>ispatcher.
> >>java:703)
> >> at
> >>org.apache.catalina.core.ApplicationDispatcher.processRequest(Appl
> >>icationDis
> >>patcher.java:463)
> >> at
> >>org.apache.catalina.core.ApplicationDispatcher.doForward(Applicati
> >>onDispatch
> >>er.java:398)
> >> at
> >>org.apache.catalina.core.ApplicationDispatcher.forward(Application
> >>Dispatcher
> >>.java:312)
> >> at
> >>org.apache.struts.action.RequestProcessor.doForward(RequestProcess
> >>or.java:10
> >>56)
> >> at
> >>org.apache.struts.action.RequestProcessor.processForwardConfig(Req
> >>uestProces
> >>sor.java:388)
> >> at
> >>org.apache.struts.action.RequestProcessor.process(RequestProcessor
> >>.java:231)
> >> at
> >>org.apache.struts.action.ActionServlet.process(ActionServlet.java:1158)
> >> at
> >>org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
> >> at javax.servlet.http.HttpServlet.service(HttpServlet.java:697)
> >> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
> >> at
> >>org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(A
> >>pplication
> >>FilterChain.java:237)
> >> at
> >>org.apache.catalina.core.ApplicationFilterChain.doFilter(Applicati
> >>onFilterCh
> >>ain.java:157)
> >> at
> >>org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapp
> >>erValve.ja
> >>va:214)
> >> at
> >>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> >>alveContex
> >>t.java:104)
> >> at
> >>org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
> >>java:520)
> >> at
> >>org.apache.catalina.core.StandardContextValve.invokeInternal(Stand
> >>ardContext
> >>Valve.java:198)
> >> at
> >>org.apache.catalina.core.StandardContextValve.invoke(StandardConte
> >>xtValve.ja
> >>va:152)
> >> at
> >>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> >>alveContex
> >>t.java:104)
> >> at
> >>org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
> >>java:520)
> >> at
> >>org.apache.catalina.core.StandardHostValve.invoke(StandardHostValv
> >>e.java:137
> >>)
> >> at
> >>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> >>alveContex
> >>t.java:104)
> >> at
> >>org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValv
> >>e.java:117
> >>)
> >> at
> >>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> >>alveContex
> >>t.java:102)
> >> at
> >>org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
> >>java:520)
> >> at
> >>org.apache.catalina.core.StandardEngineValve.invoke(StandardEngine
> >>Valve.java
> >>:109)
> >> at
> >>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> >>alveContex
> >>t.java:104)
> >> at
> >>org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
> >>java:520)
> >> at
> >>org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
> >> at
> >>org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
> >> at
> >>org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:296)
> >> at
> >>org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:372)
> >> at
> >>org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:694)
> >> at
> >>org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket
> >>.java:626)
> >> at
> >>org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:807)
> >> at
> >>org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(Thre
> >>adPool.jav
> >>a:644)
> >> at java.lang.Thread.run(Thread.java:534)
> >>
> >>
> >>** END NESTED EXCEPTION **
> >>
> >>
> >>
> >>
> >>
> >>
> >>---------------------------------------------------------------------
> >>To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> >>For additional commands, e-mail: ojb-user-help@db.apache.org
> >>
> >>
> >
> >
> >
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> >
> >
> >
>
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Re: Bug identified (was RE: SQLExcpetion)
Posted by Armin Waibel <ar...@apache.org>.
Hi Daniel,
many thanks for your detailed description and suggestion.
>
> The solution is in ConnectionManagerImpl.getConnection method. The
code is
> already there, but commented out:
>
>> // if (con == null || !isAlive(con))
>> // isAlive check, how do we react if false and we in tx?
>> // create a new connection isn't the right way I think.
>> if (con == null)
>
>
> I think this code should be applied - or at the very least, should be
> modified and applied if not inside a transaction:
>
> if (con == null || (!isInLocalTransaction() && !isAlive(con)) )
>
I will check in your patch ASAP. Additionally I think we should release
the closed connection instance and I will do a minor refactoring of
CollectionProxyDefaultImpl to handle the used PB instance more strict.
regards,
Armin
Daniel Perry wrote:
> I believe that I have solved this problem, and that there is a bug in OJB.
> I cannot be sure, but with the fix, the app has been running for 10 days now
> with no reported errors.
>
> It seems that in certain circumstances an old connection will be reused, and
> it will not be validated (or checked for being alive).
>
> The following conditions are required for the error to occur :
> 1. An object is cached (it will only happen with a long term cache - eg
> ObjectCacheDefaultImpl)
> 2. The object has been cached for long enough for the database connection
> that was used to load it has expired
> 3. The object was loaded from outside a transaction (or possibly also inside
> a very long living transaction)
> 4. A collection proxy (not sure if it affects other proxies) is materialised
> from within this
> object
>
> What seems to happen, is the connection which was used to load the object is
> held onto, and when the collection is materialised it reuses this stale
> connection and crashes out. It might also be caused if it has already been
> materialised and refresh=true - not sure how that works though.
>
> This bug will only affect people using OJB in accordance with the above
> criteria. ObjectCachePerBrokerImpl shouldn't be affected. Also the bug
> wont apply if using transactions - as when it is closed it drops the
> connection.
>
> The solution is in ConnectionManagerImpl.getConnection method. The code is
> already there, but commented out:
>
>> // if (con == null || !isAlive(con))
>> // isAlive check, how do we react if false and we in tx?
>> // create a new connection isn't the right way I think.
>> if (con == null)
>
>
> I think this code should be applied - or at the very least, should be
> modified and applied if not inside a transaction:
>
> if (con == null || (!isInLocalTransaction() && !isAlive(con)) )
>
> Daniel.
>
>
>>-----Original Message-----
>>From: Daniel Perry [mailto:d.perry@netcase.co.uk]
>>Sent: 02 November 2004 11:14
>>To: OJB Users List
>>Subject: RE: SQLExcpetion
>>
>>
>>Once again our app has started getting these errors (see trace below). It
>>seems to be happening after several days of operation.
>>
>>The problem always seems to happen when iterating over a proxied
>>collection
>>in a jsp (using jakarta JSTL c:forEach tag).
>>
>>See comments below:
>>
>>
>>>Is the error always caused by the same class
>>>
>>> >>>>at
>>> >>>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForE
>>> >>>
>>> >>>achIterator
>>>
>>>or always caused when materialized a proxied collection?
>>
>>Yes it's caused by that same class, but not always from the same jsp.
>>
>>But it's also always when proxied collections are materialised.
>>
>>
>>>Does the error occur when OJB materialize a class with clob/blob or
>>>binary/object field?
>>>
>>
>>Dont think so.
>>
>>
>>>>Is there a way for me to clear the connection pool?
>>>
>>>You can try
>>>ConnectionFactoryFactory.createConnectionFactory().releaseAllResources()
>>>CFF is a singleton. This call clear the used pool and close all
>>>connections of the pool (connections in use will be ignored AFAIK)
>>>
>>>Or extend ConnectionFactoryPooledImpl and add your own
>>
>>monitoring methods.
>>
>>
>>I've tried clearing the connection pool every hour, so the connections
>>should be fine. I havnt tried clearing the cache...
>>
>>How are connections obtained when cached objects have their proxied
>>collections materialised? (note no transactions are being used)
>>
>>I think an object is being loaded, and stuck in the cache. Days later the
>>object is being used and is having a proxied collection materialised, and
>>this is using the origional connection.
>>
>>>From what i can see in the code, a collection proxy obtains a broker, the
>>broker obtains a connection - but (and i might have got the code
>>wrong here)
>>it should reuse the broker it used when it was initally loaded,
>>and then the
>>broker reuses the conenction without checking it isnt closed :
>>ConnectionManagerImpl.getConnection
>>
>> // if (con == null || !isAlive(con))
>> // isAlive check, how do we react if false and we in tx?
>> // create a new connection isn't the right way I think.
>> if (con == null)
>>
>>This only checks if it has a connection, not if the connection is valid.
>>Maybe i should reinstate the (con == null || !isAlive(con)) ???
>>
>>Could this be the cause of my problem? or am i way off track!
>>
>>Daniel.
>>
>>Stack trace:
>>
>>org.apache.jasper.JasperException:
>>org.apache.ojb.broker.PersistenceBrokerException:
>>org.apache.ojb.broker.PersistenceBrokerSQLException:
>>java.sql.SQLException:
>>No operations allowed after connection closed.
>>
>>Connection was closed due to the following exception:
>>
>>** BEGIN NESTED EXCEPTION **
>>
>>java.sql.SQLException
>>MESSAGE: Communication link failure: java.io.IOException,
>>underlying cause:
>>Unexpected end of input stream
>>
>>** BEGIN NESTED EXCEPTION **
>>
>>java.io.IOException
>>MESSAGE: Unexpected end of input stream
>>
>>STACKTRACE:
>>
>>java.io.IOException: Unexpected end of input stream
>> at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
>> at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
>> at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
>> at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
>> at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
>> at
>>com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1496)
>> at
>>org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
>>Source)
>> at
>>org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unkno
>>wn Source)
>> at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown
>>Source)
>> at
>>org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterator(Unknown
>>Source)
>> at
>>org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFrom
>>Query(Unkn
>>own Source)
>> at
>>org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQu
>>ery(Unknow
>>n Source)
>> at
>>org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQue
>>ry(Unknown
>>Source)
>> at
>>org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQue
>>ry(Unknown
>>Source)
>> at
>>org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQu
>>ery(Unknow
>>n Source)
>> at
>>org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollecti
>>onByQuery(
>>Unknown Source)
>> at
>>org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollecti
>>onByQuery(
>>Unknown Source)
>> at
>>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadDa
>>ta(Unknown
>>Source)
>> at
>>org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
>>Source)
>> at
>>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getDat
>>a(Unknown
>>Source)
>> at
>>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.iterat
>>or(Unknown
>>Source)
>> at
>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForEa
>>chIterator
>>(ForEachSupport.java:329)
>> at
>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.support
>>edTypeForE
>>achIterator(ForEachSupport.java:205)
>> at
>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.prepare
>>(ForEachSu
>>pport.java:137)
>> at
>>javax.servlet.jsp.jstl.core.LoopTagSupport.doStartTag(LoopTagSuppo
>>rt.java:22
>>7)
>> at
>>org.apache.jsp.WEB_002dINF.jsps.manager.behavioursscreen.appraisal
>>_jsp._jspx
>>_meth_c_forEach_0(appraisal_jsp.java:294)
>> at
>>org.apache.jsp.WEB_002dINF.jsps.manager.behavioursscreen.appraisal
>>_jsp._jspS
>>ervice(appraisal_jsp.java:186)
>> at
>>org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
>> at
>>org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrap
>>per.java:2
>>98)
>> at
>>org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
>> at
>>org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
>> at
>>org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(A
>>pplication
>>FilterChain.java:237)
>> at
>>org.apache.catalina.core.ApplicationFilterChain.doFilter(Applicati
>>onFilterCh
>>ain.java:157)
>> at
>>org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationD
>>ispatcher.
>>java:703)
>> at
>>org.apache.catalina.core.ApplicationDispatcher.processRequest(Appl
>>icationDis
>>patcher.java:463)
>> at
>>org.apache.catalina.core.ApplicationDispatcher.doForward(Applicati
>>onDispatch
>>er.java:398)
>> at
>>org.apache.catalina.core.ApplicationDispatcher.forward(Application
>>Dispatcher
>>.java:312)
>> at
>>org.apache.struts.action.RequestProcessor.doForward(RequestProcess
>>or.java:10
>>56)
>> at
>>org.apache.struts.action.RequestProcessor.processForwardConfig(Req
>>uestProces
>>sor.java:388)
>> at
>>org.apache.struts.action.RequestProcessor.process(RequestProcessor
>>.java:231)
>> at
>>org.apache.struts.action.ActionServlet.process(ActionServlet.java:1158)
>> at
>>org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:697)
>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
>> at
>>org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(A
>>pplication
>>FilterChain.java:237)
>> at
>>org.apache.catalina.core.ApplicationFilterChain.doFilter(Applicati
>>onFilterCh
>>ain.java:157)
>> at
>>org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapp
>>erValve.ja
>>va:214)
>> at
>>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
>>alveContex
>>t.java:104)
>> at
>>org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
>>java:520)
>> at
>>org.apache.catalina.core.StandardContextValve.invokeInternal(Stand
>>ardContext
>>Valve.java:198)
>> at
>>org.apache.catalina.core.StandardContextValve.invoke(StandardConte
>>xtValve.ja
>>va:152)
>> at
>>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
>>alveContex
>>t.java:104)
>> at
>>org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
>>java:520)
>> at
>>org.apache.catalina.core.StandardHostValve.invoke(StandardHostValv
>>e.java:137
>>)
>> at
>>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
>>alveContex
>>t.java:104)
>> at
>>org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValv
>>e.java:117
>>)
>> at
>>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
>>alveContex
>>t.java:102)
>> at
>>org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
>>java:520)
>> at
>>org.apache.catalina.core.StandardEngineValve.invoke(StandardEngine
>>Valve.java
>>:109)
>> at
>>org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
>>alveContex
>>t.java:104)
>> at
>>org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
>>java:520)
>> at
>>org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
>> at
>>org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
>> at
>>org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:296)
>> at
>>org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:372)
>> at
>>org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:694)
>> at
>>org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket
>>.java:626)
>> at
>>org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:807)
>> at
>>org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(Thre
>>adPool.jav
>>a:644)
>> at java.lang.Thread.run(Thread.java:534)
>>
>>
>>** END NESTED EXCEPTION **
>>
>>
>>
>>
>>
>>
>>---------------------------------------------------------------------
>>To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
>>For additional commands, e-mail: ojb-user-help@db.apache.org
>>
>>
>
>
>
> ---------------------------------------------------------------------
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>
>
>
---------------------------------------------------------------------
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Bug identified (was RE: SQLExcpetion)
Posted by Daniel Perry <d....@netcase.co.uk>.
I believe that I have solved this problem, and that there is a bug in OJB.
I cannot be sure, but with the fix, the app has been running for 10 days now
with no reported errors.
It seems that in certain circumstances an old connection will be reused, and
it will not be validated (or checked for being alive).
The following conditions are required for the error to occur :
1. An object is cached (it will only happen with a long term cache - eg
ObjectCacheDefaultImpl)
2. The object has been cached for long enough for the database connection
that was used to load it has expired
3. The object was loaded from outside a transaction (or possibly also inside
a very long living transaction)
4. A collection proxy (not sure if it affects other proxies) is materialised
from within this
object
What seems to happen, is the connection which was used to load the object is
held onto, and when the collection is materialised it reuses this stale
connection and crashes out. It might also be caused if it has already been
materialised and refresh=true - not sure how that works though.
This bug will only affect people using OJB in accordance with the above
criteria. ObjectCachePerBrokerImpl shouldn't be affected. Also the bug
wont apply if using transactions - as when it is closed it drops the
connection.
The solution is in ConnectionManagerImpl.getConnection method. The code is
already there, but commented out:
>
> // if (con == null || !isAlive(con))
> // isAlive check, how do we react if false and we in tx?
> // create a new connection isn't the right way I think.
> if (con == null)
I think this code should be applied - or at the very least, should be
modified and applied if not inside a transaction:
if (con == null || (!isInLocalTransaction() && !isAlive(con)) )
Daniel.
> -----Original Message-----
> From: Daniel Perry [mailto:d.perry@netcase.co.uk]
> Sent: 02 November 2004 11:14
> To: OJB Users List
> Subject: RE: SQLExcpetion
>
>
> Once again our app has started getting these errors (see trace below). It
> seems to be happening after several days of operation.
>
> The problem always seems to happen when iterating over a proxied
> collection
> in a jsp (using jakarta JSTL c:forEach tag).
>
> See comments below:
>
> > Is the error always caused by the same class
> >
> > >>>>at
> > >>>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForE
> > >>>
> > >>>achIterator
> >
> > or always caused when materialized a proxied collection?
>
> Yes it's caused by that same class, but not always from the same jsp.
>
> But it's also always when proxied collections are materialised.
>
> >
> > Does the error occur when OJB materialize a class with clob/blob or
> > binary/object field?
> >
>
> Dont think so.
>
> > > Is there a way for me to clear the connection pool?
> >
> > You can try
> > ConnectionFactoryFactory.createConnectionFactory().releaseAllResources()
> > CFF is a singleton. This call clear the used pool and close all
> > connections of the pool (connections in use will be ignored AFAIK)
> >
> > Or extend ConnectionFactoryPooledImpl and add your own
> monitoring methods.
>
>
> I've tried clearing the connection pool every hour, so the connections
> should be fine. I havnt tried clearing the cache...
>
> How are connections obtained when cached objects have their proxied
> collections materialised? (note no transactions are being used)
>
> I think an object is being loaded, and stuck in the cache. Days later the
> object is being used and is having a proxied collection materialised, and
> this is using the origional connection.
>
> From what i can see in the code, a collection proxy obtains a broker, the
> broker obtains a connection - but (and i might have got the code
> wrong here)
> it should reuse the broker it used when it was initally loaded,
> and then the
> broker reuses the conenction without checking it isnt closed :
> ConnectionManagerImpl.getConnection
>
> // if (con == null || !isAlive(con))
> // isAlive check, how do we react if false and we in tx?
> // create a new connection isn't the right way I think.
> if (con == null)
>
> This only checks if it has a connection, not if the connection is valid.
> Maybe i should reinstate the (con == null || !isAlive(con)) ???
>
> Could this be the cause of my problem? or am i way off track!
>
> Daniel.
>
> Stack trace:
>
> org.apache.jasper.JasperException:
> org.apache.ojb.broker.PersistenceBrokerException:
> org.apache.ojb.broker.PersistenceBrokerSQLException:
> java.sql.SQLException:
> No operations allowed after connection closed.
>
> Connection was closed due to the following exception:
>
> ** BEGIN NESTED EXCEPTION **
>
> java.sql.SQLException
> MESSAGE: Communication link failure: java.io.IOException,
> underlying cause:
> Unexpected end of input stream
>
> ** BEGIN NESTED EXCEPTION **
>
> java.io.IOException
> MESSAGE: Unexpected end of input stream
>
> STACKTRACE:
>
> java.io.IOException: Unexpected end of input stream
> at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
> at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
> at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
> at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
> at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
> at
> com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1496)
> at
> org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
> Source)
> at
> org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unkno
> wn Source)
> at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown
> Source)
> at
> org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterator(Unknown
> Source)
> at
> org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFrom
> Query(Unkn
> own Source)
> at
> org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQu
> ery(Unknow
> n Source)
> at
> org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQue
> ry(Unknown
> Source)
> at
> org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQue
> ry(Unknown
> Source)
> at
> org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQu
> ery(Unknow
> n Source)
> at
> org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollecti
> onByQuery(
> Unknown Source)
> at
> org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollecti
> onByQuery(
> Unknown Source)
> at
> org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadDa
> ta(Unknown
> Source)
> at
> org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
> Source)
> at
> org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getDat
> a(Unknown
> Source)
> at
> org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.iterat
> or(Unknown
> Source)
> at
> org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForEa
> chIterator
> (ForEachSupport.java:329)
> at
> org.apache.taglibs.standard.tag.common.core.ForEachSupport.support
> edTypeForE
> achIterator(ForEachSupport.java:205)
> at
> org.apache.taglibs.standard.tag.common.core.ForEachSupport.prepare
> (ForEachSu
> pport.java:137)
> at
> javax.servlet.jsp.jstl.core.LoopTagSupport.doStartTag(LoopTagSuppo
> rt.java:22
> 7)
> at
> org.apache.jsp.WEB_002dINF.jsps.manager.behavioursscreen.appraisal
> _jsp._jspx
> _meth_c_forEach_0(appraisal_jsp.java:294)
> at
> org.apache.jsp.WEB_002dINF.jsps.manager.behavioursscreen.appraisal
> _jsp._jspS
> ervice(appraisal_jsp.java:186)
> at
> org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
> at
> org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrap
> per.java:2
> 98)
> at
> org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
> at
> org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(A
> pplication
> FilterChain.java:237)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(Applicati
> onFilterCh
> ain.java:157)
> at
> org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationD
> ispatcher.
> java:703)
> at
> org.apache.catalina.core.ApplicationDispatcher.processRequest(Appl
> icationDis
> patcher.java:463)
> at
> org.apache.catalina.core.ApplicationDispatcher.doForward(Applicati
> onDispatch
> er.java:398)
> at
> org.apache.catalina.core.ApplicationDispatcher.forward(Application
> Dispatcher
> .java:312)
> at
> org.apache.struts.action.RequestProcessor.doForward(RequestProcess
> or.java:10
> 56)
> at
> org.apache.struts.action.RequestProcessor.processForwardConfig(Req
> uestProces
> sor.java:388)
> at
> org.apache.struts.action.RequestProcessor.process(RequestProcessor
> .java:231)
> at
> org.apache.struts.action.ActionServlet.process(ActionServlet.java:1158)
> at
> org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
> at javax.servlet.http.HttpServlet.service(HttpServlet.java:697)
> at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(A
> pplication
> FilterChain.java:237)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(Applicati
> onFilterCh
> ain.java:157)
> at
> org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapp
> erValve.ja
> va:214)
> at
> org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> alveContex
> t.java:104)
> at
> org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
> java:520)
> at
> org.apache.catalina.core.StandardContextValve.invokeInternal(Stand
> ardContext
> Valve.java:198)
> at
> org.apache.catalina.core.StandardContextValve.invoke(StandardConte
> xtValve.ja
> va:152)
> at
> org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> alveContex
> t.java:104)
> at
> org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
> java:520)
> at
> org.apache.catalina.core.StandardHostValve.invoke(StandardHostValv
> e.java:137
> )
> at
> org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> alveContex
> t.java:104)
> at
> org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValv
> e.java:117
> )
> at
> org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> alveContex
> t.java:102)
> at
> org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
> java:520)
> at
> org.apache.catalina.core.StandardEngineValve.invoke(StandardEngine
> Valve.java
> :109)
> at
> org.apache.catalina.core.StandardValveContext.invokeNext(StandardV
> alveContex
> t.java:104)
> at
> org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.
> java:520)
> at
> org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
> at
> org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
> at
> org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:296)
> at
> org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:372)
> at
> org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:694)
> at
> org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket
> .java:626)
> at
> org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:807)
> at
> org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(Thre
> adPool.jav
> a:644)
> at java.lang.Thread.run(Thread.java:534)
>
>
> ** END NESTED EXCEPTION **
>
>
>
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> For additional commands, e-mail: ojb-user-help@db.apache.org
>
>
---------------------------------------------------------------------
To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
For additional commands, e-mail: ojb-user-help@db.apache.org
RE: SQLExcpetion
Posted by Daniel Perry <d....@netcase.co.uk>.
Once again our app has started getting these errors (see trace below). It
seems to be happening after several days of operation.
The problem always seems to happen when iterating over a proxied collection
in a jsp (using jakarta JSTL c:forEach tag).
See comments below:
> Is the error always caused by the same class
>
> >>>>at
> >>>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForE
> >>>
> >>>achIterator
>
> or always caused when materialized a proxied collection?
Yes it's caused by that same class, but not always from the same jsp.
But it's also always when proxied collections are materialised.
>
> Does the error occur when OJB materialize a class with clob/blob or
> binary/object field?
>
Dont think so.
> > Is there a way for me to clear the connection pool?
>
> You can try
> ConnectionFactoryFactory.createConnectionFactory().releaseAllResources()
> CFF is a singleton. This call clear the used pool and close all
> connections of the pool (connections in use will be ignored AFAIK)
>
> Or extend ConnectionFactoryPooledImpl and add your own monitoring methods.
I've tried clearing the connection pool every hour, so the connections
should be fine. I havnt tried clearing the cache...
How are connections obtained when cached objects have their proxied
collections materialised? (note no transactions are being used)
I think an object is being loaded, and stuck in the cache. Days later the
object is being used and is having a proxied collection materialised, and
this is using the origional connection.
>From what i can see in the code, a collection proxy obtains a broker, the
broker obtains a connection - but (and i might have got the code wrong here)
it should reuse the broker it used when it was initally loaded, and then the
broker reuses the conenction without checking it isnt closed :
ConnectionManagerImpl.getConnection
// if (con == null || !isAlive(con))
// isAlive check, how do we react if false and we in tx?
// create a new connection isn't the right way I think.
if (con == null)
This only checks if it has a connection, not if the connection is valid.
Maybe i should reinstate the (con == null || !isAlive(con)) ???
Could this be the cause of my problem? or am i way off track!
Daniel.
Stack trace:
org.apache.jasper.JasperException:
org.apache.ojb.broker.PersistenceBrokerException:
org.apache.ojb.broker.PersistenceBrokerSQLException: java.sql.SQLException:
No operations allowed after connection closed.
Connection was closed due to the following exception:
** BEGIN NESTED EXCEPTION **
java.sql.SQLException
MESSAGE: Communication link failure: java.io.IOException, underlying cause:
Unexpected end of input stream
** BEGIN NESTED EXCEPTION **
java.io.IOException
MESSAGE: Unexpected end of input stream
STACKTRACE:
java.io.IOException: Unexpected end of input stream
at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
at
com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1496)
at
org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
Source)
at
org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unknown Source)
at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown
Source)
at
org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterator(Unknown
Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFromQuery(Unkn
own Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQuery(Unknow
n Source)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
Source)
at
org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQuery(Unknow
n Source)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(
Unknown Source)
at
org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(
Unknown Source)
at
org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadData(Unknown
Source)
at
org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
Source)
at
org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getData(Unknown
Source)
at
org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.iterator(Unknown
Source)
at
org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForEachIterator
(ForEachSupport.java:329)
at
org.apache.taglibs.standard.tag.common.core.ForEachSupport.supportedTypeForE
achIterator(ForEachSupport.java:205)
at
org.apache.taglibs.standard.tag.common.core.ForEachSupport.prepare(ForEachSu
pport.java:137)
at
javax.servlet.jsp.jstl.core.LoopTagSupport.doStartTag(LoopTagSupport.java:22
7)
at
org.apache.jsp.WEB_002dINF.jsps.manager.behavioursscreen.appraisal_jsp._jspx
_meth_c_forEach_0(appraisal_jsp.java:294)
at
org.apache.jsp.WEB_002dINF.jsps.manager.behavioursscreen.appraisal_jsp._jspS
ervice(appraisal_jsp.java:186)
at
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
at
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:2
98)
at
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Application
FilterChain.java:237)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterCh
ain.java:157)
at
org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.
java:703)
at
org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDis
patcher.java:463)
at
org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatch
er.java:398)
at
org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher
.java:312)
at
org.apache.struts.action.RequestProcessor.doForward(RequestProcessor.java:10
56)
at
org.apache.struts.action.RequestProcessor.processForwardConfig(RequestProces
sor.java:388)
at
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:231)
at
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1158)
at
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:697)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Application
FilterChain.java:237)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterCh
ain.java:157)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.ja
va:214)
at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContex
t.java:104)
at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at
org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContext
Valve.java:198)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.ja
va:152)
at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContex
t.java:104)
at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137
)
at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContex
t.java:104)
at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117
)
at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContex
t.java:102)
at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java
:109)
at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContex
t.java:104)
at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at
org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
at
org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
at
org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:296)
at
org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:372)
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:694)
at
org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:626)
at
org.apache.jk.common.SocketConnection.runIt(ChannelSocket.java:807)
at
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.jav
a:644)
at java.lang.Thread.run(Thread.java:534)
** END NESTED EXCEPTION **
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Re: SQLExcpetion
Posted by Armin Waibel <ar...@apache.org>.
Hi Daniel,
Daniel Perry wrote:
> I'm still getting these errors in my app.
>
> Currently i'm using i've got ConnectionFactoryPooledImpl set in
> ojb.properties, and in the repository_database.xml i have the following in
> my jdbc-connection-descriptor:
>
> <connection-pool
> minActive="5"
> maxActive="50"
> whenExhaustedAction="2"
> validationQuery="select count(*) from OJB_HL_SEQ"
> />
>
> Is there a reason i would get these errors? Surely the connection pool
> should be validating the connection before handing it out, and then it
> should be fine?
>
I doubt that the ConnectionFactory implementation cause this error,
because it's the first time I heard about such a problem and the
validation query is working AFAIK (did you check this by logging the sql
statements e.g. with p6spy?)
> Is ConnectionFactoryDBCPImpl any better than the one i'm using?
>
Both ConnectionFactory implementations use commons-pool, but DBCP is a
JDBC/Pool/Datasource api build on top of commons-pool. If this
implementation will work you found a bug in ConnectionFactoryPooledImpl ;-)
> I am considering switching to ConnectionFactoryNotPooledImpl, but it would
> mean a big performance hit!
>
Is the error always caused by the same class
>>>>at
>>>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForE
>>>
>>>achIterator
or always caused when materialized a proxied collection?
Does the error occur when OJB materialize a class with clob/blob or
binary/object field?
> Is there a way for me to clear the connection pool?
You can try
ConnectionFactoryFactory.createConnectionFactory().releaseAllResources()
CFF is a singleton. This call clear the used pool and close all
connections of the pool (connections in use will be ignored AFAIK)
Or extend ConnectionFactoryPooledImpl and add your own monitoring methods.
regards,
Armin
> As it's only when the
> system has been running for a while that i see these errors, i figure if i
> clear the pool every half hour, it should stop it!
>
> Daniel.
>
>
>
>>-----Original Message-----
>>From: Daniel Perry [mailto:d.perry@netcase.co.uk]
>>Sent: 11 October 2004 16:20
>>To: OJB Users List
>>Subject: RE: SQLExcpetion
>>
>>
>>Ah i forgot to mention - mysql and tomcat are on the same machine :) which
>>kinda counts out network problems.
>>
>>I cant see any reason why i'd get these errors (at least on a 1 machine
>>system). The connection pool should prevent them happening due to
>>timeouts/etc. If it doesnt, then i'd expect to find that mysql had died,
>>and the system to remain down until it had been started up again.
>>
>>Daniel.
>>
>>
>>
>>
>>>-----Original Message-----
>>>From: Edson Carlos Ericksson Richter
>>>[mailto:edson.richter@mgrinformatica.com.br]
>>>Sent: 11 October 2004 16:07
>>>To: OJB Users List
>>>Subject: Re: SQLExcpetion
>>>
>>>
>>>If you try to copy large files between machines, you get Connection
>>>Reset (or connection reset by peer, in some OSes)??? If so, you get a
>>>trahsed network card or network hub... I had this problem some time ago,
>>>and I had to exchange a hub with some ports "burned", sending trash in
>>>my network...
>>>
>>>Just my 2c,
>>>
>>>Richter
>>>
>>>Daniel Perry escreveu:
>>>
>>>
>>>>Hi all,
>>>>
>>>>One of our systems has been running fine (live) for the last few
>>>
>>>weeks until
>>>
>>>>yesterday when for about half an hour it started randomly
>>
>>crashing. Since
>>
>>>>then it has been fine! The (partial) exception trace is below.
>>>
>>>>From what i
>>>
>>>>can figure the problem is coming from dud mysql connections.
>>
>>However, i
>>
>>>>thought that OJB checked the connection before using it by using the
>>>>validation query?
>>>>
>>>>I'm using OJB 1.0.0, mysql-connector 3.0.10, and mysql 4.0.18.
>>>>
>>>>Any ideas about what would cause this? Anyway i can prevent
>>
>>it occuring
>>
>>>>again?
>>>>
>>>>Thanks,
>>>>Daniel.
>>>>
>>>>
>>>>
>>>>
>>>>[org.apache.ojb.broker.accesslayer.StatementsForClassImpl] ERROR: No
>>>>operations allowed after connection closed.
>>>>
>>>>Connection was closed due to the following exception:
>>>>
>>>>** BEGIN NESTED EXCEPTION **
>>>>
>>>>java.sql.SQLException
>>>>MESSAGE: Communication link failure: java.io.IOException,
>>>
>>>underlying cause:
>>>
>>>>Unexpected end of input stream
>>>>
>>>>** BEGIN NESTED EXCEPTION **
>>>>
>>>>java.io.IOException
>>>>MESSAGE: Unexpected end of input stream
>>>>
>>>>STACKTRACE:
>>>>
>>>>java.io.IOException: Unexpected end of input stream
>>>>at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
>>>>at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
>>>>at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
>>>>at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
>>>>at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
>>>>at
>>>>com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.j
>>>
>>>ava:1496)
>>>
>>>>at
>>
>>org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
>>
>>>>Source)
>>>>at
>>
>>org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unknown
>>
>>>>Source)
>>>>at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown Source)
>>>>at
>>>
>>>org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterator(Unknown
>>>
>>>>Source)
>>>>at
>>>>org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFro
>>>
>>>mQuery(Unkn
>>>
>>>>own Source)
>>>>at
>>>>org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQ
>>>
>>>uery(Unknow
>>>
>>>>n Source)
>>>>at
>>>>org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQu
>>>
>>>ery(Unknown
>>>
>>>>Source)
>>>>at
>>>>org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQu
>>>
>>>ery(Unknown
>>>
>>>>Source)
>>>>at
>>>>org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQ
>>>
>>>uery(Unknow
>>>
>>>>n Source)
>>>>at
>>>>org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollect
>>>
>>>ionByQuery(
>>>
>>>>Unknown Source)
>>>>at
>>>>org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollect
>>>
>>>ionByQuery(
>>>
>>>>Unknown Source)
>>>>at
>>>>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadD
>>>
>>>ata(Unknown
>>>
>>>>Source)
>>>>at
>>>
>>>org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
>>>
>>>>Source)
>>>>at
>>>>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getDa
>>>
>>>ta(Unknown
>>>
>>>>Source)
>>>>at
>>>>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.itera
>>>
>>>tor(Unknown
>>>
>>>>Source)
>>>>at
>>>>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForE
>>>
>>>achIterator
>>>
>>>>(ForEachSupport.java:329)
>>>>
>>>>
>>>>---------------------------------------------------------------------
>>>>To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
>>>>For additional commands, e-mail: ojb-user-help@db.apache.org
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>---------------------------------------------------------------------
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>>>For additional commands, e-mail: ojb-user-help@db.apache.org
>>>
>>>
>>
>>
>>---------------------------------------------------------------------
>>To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
>>For additional commands, e-mail: ojb-user-help@db.apache.org
>>
>>
>
>
>
> ---------------------------------------------------------------------
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> For additional commands, e-mail: ojb-user-help@db.apache.org
>
>
>
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SQLExcpetion
Posted by Daniel Perry <d....@netcase.co.uk>.
I'm still getting these errors in my app.
Currently i'm using i've got ConnectionFactoryPooledImpl set in
ojb.properties, and in the repository_database.xml i have the following in
my jdbc-connection-descriptor:
<connection-pool
minActive="5"
maxActive="50"
whenExhaustedAction="2"
validationQuery="select count(*) from OJB_HL_SEQ"
/>
Is there a reason i would get these errors? Surely the connection pool
should be validating the connection before handing it out, and then it
should be fine?
Is ConnectionFactoryDBCPImpl any better than the one i'm using?
I am considering switching to ConnectionFactoryNotPooledImpl, but it would
mean a big performance hit!
Is there a way for me to clear the connection pool? As it's only when the
system has been running for a while that i see these errors, i figure if i
clear the pool every half hour, it should stop it!
Daniel.
> -----Original Message-----
> From: Daniel Perry [mailto:d.perry@netcase.co.uk]
> Sent: 11 October 2004 16:20
> To: OJB Users List
> Subject: RE: SQLExcpetion
>
>
> Ah i forgot to mention - mysql and tomcat are on the same machine :) which
> kinda counts out network problems.
>
> I cant see any reason why i'd get these errors (at least on a 1 machine
> system). The connection pool should prevent them happening due to
> timeouts/etc. If it doesnt, then i'd expect to find that mysql had died,
> and the system to remain down until it had been started up again.
>
> Daniel.
>
>
>
> > -----Original Message-----
> > From: Edson Carlos Ericksson Richter
> > [mailto:edson.richter@mgrinformatica.com.br]
> > Sent: 11 October 2004 16:07
> > To: OJB Users List
> > Subject: Re: SQLExcpetion
> >
> >
> > If you try to copy large files between machines, you get Connection
> > Reset (or connection reset by peer, in some OSes)??? If so, you get a
> > trahsed network card or network hub... I had this problem some time ago,
> > and I had to exchange a hub with some ports "burned", sending trash in
> > my network...
> >
> > Just my 2c,
> >
> > Richter
> >
> > Daniel Perry escreveu:
> >
> > >Hi all,
> > >
> > >One of our systems has been running fine (live) for the last few
> > weeks until
> > >yesterday when for about half an hour it started randomly
> crashing. Since
> > >then it has been fine! The (partial) exception trace is below.
> > From what i
> > >can figure the problem is coming from dud mysql connections.
> However, i
> > >thought that OJB checked the connection before using it by using the
> > >validation query?
> > >
> > >I'm using OJB 1.0.0, mysql-connector 3.0.10, and mysql 4.0.18.
> > >
> > >Any ideas about what would cause this? Anyway i can prevent
> it occuring
> > >again?
> > >
> > >Thanks,
> > >Daniel.
> > >
> > >
> > >
> > >
> > >[org.apache.ojb.broker.accesslayer.StatementsForClassImpl] ERROR: No
> > >operations allowed after connection closed.
> > >
> > >Connection was closed due to the following exception:
> > >
> > >** BEGIN NESTED EXCEPTION **
> > >
> > >java.sql.SQLException
> > >MESSAGE: Communication link failure: java.io.IOException,
> > underlying cause:
> > >Unexpected end of input stream
> > >
> > >** BEGIN NESTED EXCEPTION **
> > >
> > >java.io.IOException
> > >MESSAGE: Unexpected end of input stream
> > >
> > >STACKTRACE:
> > >
> > >java.io.IOException: Unexpected end of input stream
> > > at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
> > > at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
> > > at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
> > > at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
> > > at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
> > > at
> > >com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.j
> > ava:1496)
> > > at
> org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
> > >Source)
> > > at
> org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unknown
> > >Source)
> > > at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown Source)
> > > at
> >
> >org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterator(Unknown
> > >Source)
> > > at
> > >org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFro
> > mQuery(Unkn
> > >own Source)
> > > at
> > >org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQ
> > uery(Unknow
> > >n Source)
> > > at
> > >org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQu
> > ery(Unknown
> > >Source)
> > > at
> > >org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQu
> > ery(Unknown
> > >Source)
> > > at
> > >org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQ
> > uery(Unknow
> > >n Source)
> > > at
> > >org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollect
> > ionByQuery(
> > >Unknown Source)
> > > at
> > >org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollect
> > ionByQuery(
> > >Unknown Source)
> > > at
> > >org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadD
> > ata(Unknown
> > >Source)
> > > at
> > org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
> > >Source)
> > > at
> > >org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getDa
> > ta(Unknown
> > >Source)
> > > at
> > >org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.itera
> > tor(Unknown
> > >Source)
> > > at
> > >org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForE
> > achIterator
> > >(ForEachSupport.java:329)
> > >
> > >
> > >---------------------------------------------------------------------
> > >To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> > >For additional commands, e-mail: ojb-user-help@db.apache.org
> > >
> > >
> > >
> > >
> > >
> >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> > For additional commands, e-mail: ojb-user-help@db.apache.org
> >
> >
>
>
> ---------------------------------------------------------------------
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> For additional commands, e-mail: ojb-user-help@db.apache.org
>
>
---------------------------------------------------------------------
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RE: SQLExcpetion
Posted by Daniel Perry <d....@netcase.co.uk>.
Ah i forgot to mention - mysql and tomcat are on the same machine :) which
kinda counts out network problems.
I cant see any reason why i'd get these errors (at least on a 1 machine
system). The connection pool should prevent them happening due to
timeouts/etc. If it doesnt, then i'd expect to find that mysql had died,
and the system to remain down until it had been started up again.
Daniel.
> -----Original Message-----
> From: Edson Carlos Ericksson Richter
> [mailto:edson.richter@mgrinformatica.com.br]
> Sent: 11 October 2004 16:07
> To: OJB Users List
> Subject: Re: SQLExcpetion
>
>
> If you try to copy large files between machines, you get Connection
> Reset (or connection reset by peer, in some OSes)??? If so, you get a
> trahsed network card or network hub... I had this problem some time ago,
> and I had to exchange a hub with some ports "burned", sending trash in
> my network...
>
> Just my 2c,
>
> Richter
>
> Daniel Perry escreveu:
>
> >Hi all,
> >
> >One of our systems has been running fine (live) for the last few
> weeks until
> >yesterday when for about half an hour it started randomly crashing. Since
> >then it has been fine! The (partial) exception trace is below.
> From what i
> >can figure the problem is coming from dud mysql connections. However, i
> >thought that OJB checked the connection before using it by using the
> >validation query?
> >
> >I'm using OJB 1.0.0, mysql-connector 3.0.10, and mysql 4.0.18.
> >
> >Any ideas about what would cause this? Anyway i can prevent it occuring
> >again?
> >
> >Thanks,
> >Daniel.
> >
> >
> >
> >
> >[org.apache.ojb.broker.accesslayer.StatementsForClassImpl] ERROR: No
> >operations allowed after connection closed.
> >
> >Connection was closed due to the following exception:
> >
> >** BEGIN NESTED EXCEPTION **
> >
> >java.sql.SQLException
> >MESSAGE: Communication link failure: java.io.IOException,
> underlying cause:
> >Unexpected end of input stream
> >
> >** BEGIN NESTED EXCEPTION **
> >
> >java.io.IOException
> >MESSAGE: Unexpected end of input stream
> >
> >STACKTRACE:
> >
> >java.io.IOException: Unexpected end of input stream
> > at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
> > at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
> > at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
> > at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
> > at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
> > at
> >com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.j
> ava:1496)
> > at org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
> >Source)
> > at org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unknown
> >Source)
> > at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown Source)
> > at
> >org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterator(Unknown
> >Source)
> > at
> >org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFro
> mQuery(Unkn
> >own Source)
> > at
> >org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQ
> uery(Unknow
> >n Source)
> > at
> >org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQu
> ery(Unknown
> >Source)
> > at
> >org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQu
> ery(Unknown
> >Source)
> > at
> >org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQ
> uery(Unknow
> >n Source)
> > at
> >org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollect
> ionByQuery(
> >Unknown Source)
> > at
> >org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollect
> ionByQuery(
> >Unknown Source)
> > at
> >org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadD
> ata(Unknown
> >Source)
> > at
> org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
> >Source)
> > at
> >org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getDa
> ta(Unknown
> >Source)
> > at
> >org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.itera
> tor(Unknown
> >Source)
> > at
> >org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForE
> achIterator
> >(ForEachSupport.java:329)
> >
> >
> >---------------------------------------------------------------------
> >To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> >For additional commands, e-mail: ojb-user-help@db.apache.org
> >
> >
> >
> >
> >
>
>
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Re: SQLExcpetion
Posted by Edson Carlos Ericksson Richter <ed...@mgrinformatica.com.br>.
If you try to copy large files between machines, you get Connection
Reset (or connection reset by peer, in some OSes)??? If so, you get a
trahsed network card or network hub... I had this problem some time ago,
and I had to exchange a hub with some ports "burned", sending trash in
my network...
Just my 2c,
Richter
Daniel Perry escreveu:
>Hi all,
>
>One of our systems has been running fine (live) for the last few weeks until
>yesterday when for about half an hour it started randomly crashing. Since
>then it has been fine! The (partial) exception trace is below. From what i
>can figure the problem is coming from dud mysql connections. However, i
>thought that OJB checked the connection before using it by using the
>validation query?
>
>I'm using OJB 1.0.0, mysql-connector 3.0.10, and mysql 4.0.18.
>
>Any ideas about what would cause this? Anyway i can prevent it occuring
>again?
>
>Thanks,
>Daniel.
>
>
>
>
>[org.apache.ojb.broker.accesslayer.StatementsForClassImpl] ERROR: No
>operations allowed after connection closed.
>
>Connection was closed due to the following exception:
>
>** BEGIN NESTED EXCEPTION **
>
>java.sql.SQLException
>MESSAGE: Communication link failure: java.io.IOException, underlying cause:
>Unexpected end of input stream
>
>** BEGIN NESTED EXCEPTION **
>
>java.io.IOException
>MESSAGE: Unexpected end of input stream
>
>STACKTRACE:
>
>java.io.IOException: Unexpected end of input stream
> at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1455)
> at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1826)
> at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1098)
> at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1192)
> at com.mysql.jdbc.Connection.execSQL(Connection.java:2051)
> at
>com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1496)
> at org.apache.ojb.broker.accesslayer.JdbcAccessImpl.executeQuery(Unknown
>Source)
> at org.apache.ojb.broker.accesslayer.RsQueryObject.performQuery(Unknown
>Source)
> at org.apache.ojb.broker.accesslayer.RsIterator.<init>(Unknown Source)
> at
>org.apache.ojb.broker.core.RsIteratorFactoryImpl.createRsIterator(Unknown
>Source)
> at
>org.apache.ojb.broker.core.PersistenceBrokerImpl.getRsIteratorFromQuery(Unkn
>own Source)
> at
>org.apache.ojb.broker.core.PersistenceBrokerImpl.getIteratorFromQuery(Unknow
>n Source)
> at
>org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
>Source)
> at
>org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(Unknown
>Source)
> at
>org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQuery(Unknow
>n Source)
> at
>org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(
>Unknown Source)
> at
>org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(
>Unknown Source)
> at
>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.loadData(Unknown
>Source)
> at org.apache.ojb.broker.core.proxy.ListProxyDefaultImpl.loadData(Unknown
>Source)
> at
>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.getData(Unknown
>Source)
> at
>org.apache.ojb.broker.core.proxy.CollectionProxyDefaultImpl.iterator(Unknown
>Source)
> at
>org.apache.taglibs.standard.tag.common.core.ForEachSupport.toForEachIterator
>(ForEachSupport.java:329)
>
>
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