RE: [JBoss-dev] NPE when using DefaultDS
Ok, I have done some investigation into this and I think I am understanding the problem, I'm just not too sure of the best solution. I would appreciate the opinion of someone who has worked with this code before. The problem is that when a statement obtained from a given jdbc connection throws a SQL exception the connection (through a rather convoluted series of method calls) is being closed. If the client program then tries to create another statement using the same connection a null pointer exception results because the underlying connection is returning a null, having been closed already. Whether this (the connection returning null instead of throwing another SQL excpetion, which is what you would expect from a closed connection) is what should happen or not is kinda beside the point, it is what is happening, and it is happening because our resource and pooling code decides to destroy the connection when a statement from the connection throws an error. So I guess my question is why do we do this? Is there some convention with jdbc I am unaware of that suggests a connection should become unusuable after a statement obtained from that connection throws an error? Or is there some other good reason we are doing this? If so I can change the code so that any attempted use of the connection in this situation will result in a SQL exception rather than a NPE. If there is no particular reason we are doing this then I will (try) to change the code so we don't do this! Guidence from someone who is familiar with this code would be appreciated, else I am going to bang on by myself and can't guarantee the results :-) Thanks David. -Original Message- From: Peter Fagerlund [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 28, 2001 12:40 PM To: David Maplesden; JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS While pooking around i found and : Uncommented body of deleteObject(pooledObject) - line 71 of org/jboss/resource/connectionmanager.ManagedConnectionPoolFactory.java (it seems this is called when the pool shrinks or is shut down. some test -is shrinking the pool to [0/0/10] and as a effect the next test using the DefaultDS do not have a connection ? ... it should probably create one before trying to create a table ? ...) *** Now when running run-testsuite I have 169 tests running and 1 error 99.41% Success rate - heh ... So the xa test is failing above - We knew that - and disabeling it should render a cool 100% of the 169 tests ! ... /peter_f on 1-11-26 22.54, David Maplesden at [EMAIL PROTECTED] wrote: I have been experiencing a NPE when calling createStatement on a connection obtained from DefaultDS. java.lang.NullPointerException at org.jboss.resource.adapter.jdbc.local.StatementInPool.init(S tatementInPool .java:35) at org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createS tatement(Conne ctionInPool.java:606) This doesn't always occur and I have only noticed it in the last week or so, previously it worked fine. It occurs after a previous statement throws an SQLException. In other words if you are using the connections from DefaultDS everything is fine until one of your SQL queries causes an SQL exception. After this point you get a NPE every time you try to create another statement from a connection for DefaultDS. I think (though I don't know for sure) that it has been caused by a change to the Object pool code made last week sometime. I hope someone out there can help. Thanks David. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
Re: [JBoss-dev] NPE when using DefaultDS
What I found ? was -it seems (when looking at the log) -that it is only the BMP-test that has this behavior ? ... and maybe rewriting that would solve it ? ... the result would then *only* be to hide this feature ? ... not what We want really ... /peter_f on 1-11-29 21.57, David Maplesden at [EMAIL PROTECTED] wrote: Ok, I have done some investigation into this and I think I am understanding the problem, I'm just not too sure of the best solution. I would appreciate the opinion of someone who has worked with this code before. The problem is that when a statement obtained from a given jdbc connection throws a SQL exception the connection (through a rather convoluted series of method calls) is being closed. If the client program then tries to create another statement using the same connection a null pointer exception results because the underlying connection is returning a null, having been closed already. Whether this (the connection returning null instead of throwing another SQL excpetion, which is what you would expect from a closed connection) is what should happen or not is kinda beside the point, it is what is happening, and it is happening because our resource and pooling code decides to destroy the connection when a statement from the connection throws an error. So I guess my question is why do we do this? Is there some convention with jdbc I am unaware of that suggests a connection should become unusuable after a statement obtained from that connection throws an error? Or is there some other good reason we are doing this? If so I can change the code so that any attempted use of the connection in this situation will result in a SQL exception rather than a NPE. If there is no particular reason we are doing this then I will (try) to change the code so we don't do this! Guidence from someone who is familiar with this code would be appreciated, else I am going to bang on by myself and can't guarantee the results :-) Thanks David. -Original Message- From: Peter Fagerlund [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 28, 2001 12:40 PM To: David Maplesden; JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS While pooking around i found and : Uncommented body of deleteObject(pooledObject) - line 71 of org/jboss/resource/connectionmanager.ManagedConnectionPoolFactory.java (it seems this is called when the pool shrinks or is shut down. some test -is shrinking the pool to [0/0/10] and as a effect the next test using the DefaultDS do not have a connection ? ... it should probably create one before trying to create a table ? ...) *** Now when running run-testsuite I have 169 tests running and 1 error 99.41% Success rate - heh ... So the xa test is failing above - We knew that - and disabeling it should render a cool 100% of the 169 tests ! ... /peter_f on 1-11-26 22.54, David Maplesden at [EMAIL PROTECTED] wrote: I have been experiencing a NPE when calling createStatement on a connection obtained from DefaultDS. java.lang.NullPointerException at org.jboss.resource.adapter.jdbc.local.StatementInPool.init(S tatementInPool .java:35) at org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createS tatement(Conne ctionInPool.java:606) This doesn't always occur and I have only noticed it in the last week or so, previously it worked fine. It occurs after a previous statement throws an SQLException. In other words if you are using the connections from DefaultDS everything is fine until one of your SQL queries causes an SQL exception. After this point you get a NPE every time you try to create another statement from a connection for DefaultDS. I think (though I don't know for sure) that it has been caused by a change to the Object pool code made last week sometime. I hope someone out there can help. Thanks David. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
Re: [JBoss-dev] NPE when using DefaultDS
The destroy logic was just changed by thedug, so the validity of the changes needs to be justified. I would suggest backing out the change since it seemed to be an unthinking merge from a 2.4 change that may have no relevance to the 3.0 codebase. There were two changes to jbosscx/src/main/org/jboss/resource/connectionmanager/ManagedConnectionPoolF actory.java This needs to be rolled back to version 1.2 to undo the changes. - Original Message - From: David Maplesden [EMAIL PROTECTED] To: JBossDev (E-mail) [EMAIL PROTECTED] Sent: Thursday, November 29, 2001 12:57 PM Subject: RE: [JBoss-dev] NPE when using DefaultDS Ok, I have done some investigation into this and I think I am understanding the problem, I'm just not too sure of the best solution. I would appreciate the opinion of someone who has worked with this code before. The problem is that when a statement obtained from a given jdbc connection throws a SQL exception the connection (through a rather convoluted series of method calls) is being closed. If the client program then tries to create another statement using the same connection a null pointer exception results because the underlying connection is returning a null, having been closed already. Whether this (the connection returning null instead of throwing another SQL excpetion, which is what you would expect from a closed connection) is what should happen or not is kinda beside the point, it is what is happening, and it is happening because our resource and pooling code decides to destroy the connection when a statement from the connection throws an error. So I guess my question is why do we do this? Is there some convention with jdbc I am unaware of that suggests a connection should become unusuable after a statement obtained from that connection throws an error? Or is there some other good reason we are doing this? If so I can change the code so that any attempted use of the connection in this situation will result in a SQL exception rather than a NPE. If there is no particular reason we are doing this then I will (try) to change the code so we don't do this! Guidence from someone who is familiar with this code would be appreciated, else I am going to bang on by myself and can't guarantee the results :-) Thanks David. -Original Message- From: Peter Fagerlund [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 28, 2001 12:40 PM To: David Maplesden; JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS While pooking around i found and : Uncommented body of deleteObject(pooledObject) - line 71 of org/jboss/resource/connectionmanager.ManagedConnectionPoolFactory.java (it seems this is called when the pool shrinks or is shut down. some test -is shrinking the pool to [0/0/10] and as a effect the next test using the DefaultDS do not have a connection ? ... it should probably create one before trying to create a table ? ...) *** Now when running run-testsuite I have 169 tests running and 1 error 99.41% Success rate - heh ... So the xa test is failing above - We knew that - and disabeling it should render a cool 100% of the 169 tests ! ... /peter_f on 1-11-26 22.54, David Maplesden at [EMAIL PROTECTED] wrote: I have been experiencing a NPE when calling createStatement on a connection obtained from DefaultDS. java.lang.NullPointerException at org.jboss.resource.adapter.jdbc.local.StatementInPool.init(S tatementInPool .java:35) at org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createS tatement(Conne ctionInPool.java:606) This doesn't always occur and I have only noticed it in the last week or so, previously it worked fine. It occurs after a previous statement throws an SQLException. In other words if you are using the connections from DefaultDS everything is fine until one of your SQL queries causes an SQL exception. After this point you get a NPE every time you try to create another statement from a connection for DefaultDS. I think (though I don't know for sure) that it has been caused by a change to the Object pool code made last week sometime. I hope someone out there can help. Thanks David. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus
Re: [JBoss-dev] NPE when using DefaultDS
on 1-11-29 21.57, David Maplesden at [EMAIL PROTECTED] wrote: and it is happening because our resource and pooling code decides to destroy the connection when a statement from the connection throws an error. could it not be left open ? ... that is : -there is a connention from pool to db ... why close it ? unless it is a broken connection inbetween pool - db right now when app - pooledConnection - db and the db returns a exception pooledConnection goes out of scoope ... and app is left hanging ... me trying to understand ... /peter_f ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
RE: [JBoss-dev] NPE when using DefaultDS
Yes, it was Doug's change that allowed the bug to surface, but on the face of it Doug's change seems a valid one to me, when a managed connection is being deleted from a pool the underlying connection should be closed. I think Doug's change is just showing up some bad handling of the situation that was going unnoticed previously. The problem is being caused by the fact that when the underlying connection is closed the client still has a reference to the connection wrapper, and calling createStatement on this results in a null pointer exception rather than an SQL exception. Of course the other question I was looking for an answer to is why is the connection being closed when a statement throws an exception? Does it need to be? I think there are two things here to fix. David. -Original Message- From: Scott M Stark [mailto:[EMAIL PROTECTED]] Sent: Friday, November 30, 2001 10:41 AM To: JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS The destroy logic was just changed by thedug, so the validity of the changes needs to be justified. I would suggest backing out the change since it seemed to be an unthinking merge from a 2.4 change that may have no relevance to the 3.0 codebase. There were two changes to jbosscx/src/main/org/jboss/resource/connectionmanager/ManagedC onnectionPoolF actory.java This needs to be rolled back to version 1.2 to undo the changes. - Original Message - From: David Maplesden [EMAIL PROTECTED] To: JBossDev (E-mail) [EMAIL PROTECTED] Sent: Thursday, November 29, 2001 12:57 PM Subject: RE: [JBoss-dev] NPE when using DefaultDS Ok, I have done some investigation into this and I think I am understanding the problem, I'm just not too sure of the best solution. I would appreciate the opinion of someone who has worked with this code before. The problem is that when a statement obtained from a given jdbc connection throws a SQL exception the connection (through a rather convoluted series of method calls) is being closed. If the client program then tries to create another statement using the same connection a null pointer exception results because the underlying connection is returning a null, having been closed already. Whether this (the connection returning null instead of throwing another SQL excpetion, which is what you would expect from a closed connection) is what should happen or not is kinda beside the point, it is what is happening, and it is happening because our resource and pooling code decides to destroy the connection when a statement from the connection throws an error. So I guess my question is why do we do this? Is there some convention with jdbc I am unaware of that suggests a connection should become unusuable after a statement obtained from that connection throws an error? Or is there some other good reason we are doing this? If so I can change the code so that any attempted use of the connection in this situation will result in a SQL exception rather than a NPE. If there is no particular reason we are doing this then I will (try) to change the code so we don't do this! Guidence from someone who is familiar with this code would be appreciated, else I am going to bang on by myself and can't guarantee the results :-) Thanks David. -Original Message- From: Peter Fagerlund [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 28, 2001 12:40 PM To: David Maplesden; JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS While pooking around i found and : Uncommented body of deleteObject(pooledObject) - line 71 of org/jboss/resource/connectionmanager.ManagedConnectionPoolFactory.java (it seems this is called when the pool shrinks or is shut down. some test -is shrinking the pool to [0/0/10] and as a effect the next test using the DefaultDS do not have a connection ? ... it should probably create one before trying to create a table ? ...) *** Now when running run-testsuite I have 169 tests running and 1 error 99.41% Success rate - heh ... So the xa test is failing above - We knew that - and disabeling it should render a cool 100% of the 169 tests ! ... /peter_f on 1-11-26 22.54, David Maplesden at [EMAIL PROTECTED] wrote: I have been experiencing a NPE when calling createStatement on a connection obtained from DefaultDS. java.lang.NullPointerException at org.jboss.resource.adapter.jdbc.local.StatementInPool.init(S tatementInPool .java:35) at org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createS tatement(Conne ctionInPool.java:606) This doesn't always occur and I have only noticed it in the last week or so, previously it worked fine. It occurs after a previous statement throws
Re: [JBoss-dev] NPE when using DefaultDS
You probably now know more about this is implemented than anyone else at the moment ;-). I haven't looked at this for a while but I think the following is more or less accurate. The problem IMHO is deciding when a fatal error has occured. When it has, the ConnectionManager is supposed to call ManagedConnection.destroy and remove the ManagedConnection from the pool. I think perhaps Doug's recent changes had something to do with this: when the connection dies, you definitely want to ditch the ManagedConnection. However, if you just try to execute some invalid sql, everything is still fine. I haven't looked into sorting SQLExceptions lately. Is there a reasonable way to distinguish fatal from non-fatal exceptions? david jencks On 2001.11.29 15:57:37 -0500 David Maplesden wrote: Ok, I have done some investigation into this and I think I am understanding the problem, I'm just not too sure of the best solution. I would appreciate the opinion of someone who has worked with this code before. The problem is that when a statement obtained from a given jdbc connection throws a SQL exception the connection (through a rather convoluted series of method calls) is being closed. If the client program then tries to create another statement using the same connection a null pointer exception results because the underlying connection is returning a null, having been closed already. Whether this (the connection returning null instead of throwing another SQL excpetion, which is what you would expect from a closed connection) is what should happen or not is kinda beside the point, it is what is happening, and it is happening because our resource and pooling code decides to destroy the connection when a statement from the connection throws an error. So I guess my question is why do we do this? Is there some convention with jdbc I am unaware of that suggests a connection should become unusuable after a statement obtained from that connection throws an error? Or is there some other good reason we are doing this? If so I can change the code so that any attempted use of the connection in this situation will result in a SQL exception rather than a NPE. If there is no particular reason we are doing this then I will (try) to change the code so we don't do this! Guidence from someone who is familiar with this code would be appreciated, else I am going to bang on by myself and can't guarantee the results :-) Thanks David. -Original Message- From: Peter Fagerlund [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 28, 2001 12:40 PM To: David Maplesden; JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS While pooking around i found and : Uncommented body of deleteObject(pooledObject) - line 71 of org/jboss/resource/connectionmanager.ManagedConnectionPoolFactory.java (it seems this is called when the pool shrinks or is shut down. some test -is shrinking the pool to [0/0/10] and as a effect the next test using the DefaultDS do not have a connection ? ... it should probably create one before trying to create a table ? ...) *** Now when running run-testsuite I have 169 tests running and 1 error 99.41% Success rate - heh ... So the xa test is failing above - We knew that - and disabeling it should render a cool 100% of the 169 tests ! ... /peter_f on 1-11-26 22.54, David Maplesden at [EMAIL PROTECTED] wrote: I have been experiencing a NPE when calling createStatement on a connection obtained from DefaultDS. java.lang.NullPointerException at org.jboss.resource.adapter.jdbc.local.StatementInPool.init(S tatementInPool .java:35) at org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createS tatement(Conne ctionInPool.java:606) This doesn't always occur and I have only noticed it in the last week or so, previously it worked fine. It occurs after a previous statement throws an SQLException. In other words if you are using the connections from DefaultDS everything is fine until one of your SQL queries causes an SQL exception. After this point you get a NPE every time you try to create another statement from a connection for DefaultDS. I think (though I don't know for sure) that it has been caused by a change to the Object pool code made last week sometime. I hope someone out there can help. Thanks David. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list
RE: [JBoss-dev] NPE when using DefaultDS
I don't know if you do have to distinguish between fatal and non-fatal errors though. If the error was fatal then the next time the underlying connection is accessed then it will indicate this by throwing a SQL exception of its own. I guess this is not ideal as you want to avoid returning a bad connection to the pool, but we have no indication that the connection is bad, simply because a statement threw an exception. I think we wait until a connection throws an exception of its own before we declare it as bad. David -Original Message- From: David Jencks [mailto:[EMAIL PROTECTED]] Sent: Friday, November 30, 2001 10:57 AM To: David Maplesden Cc: JBossDev Subject: Re: [JBoss-dev] NPE when using DefaultDS You probably now know more about this is implemented than anyone else at the moment ;-). I haven't looked at this for a while but I think the following is more or less accurate. The problem IMHO is deciding when a fatal error has occured. When it has, the ConnectionManager is supposed to call ManagedConnection.destroy and remove the ManagedConnection from the pool. I think perhaps Doug's recent changes had something to do with this: when the connection dies, you definitely want to ditch the ManagedConnection. However, if you just try to execute some invalid sql, everything is still fine. I haven't looked into sorting SQLExceptions lately. Is there a reasonable way to distinguish fatal from non-fatal exceptions? david jencks On 2001.11.29 15:57:37 -0500 David Maplesden wrote: Ok, I have done some investigation into this and I think I am understanding the problem, I'm just not too sure of the best solution. I would appreciate the opinion of someone who has worked with this code before. The problem is that when a statement obtained from a given jdbc connection throws a SQL exception the connection (through a rather convoluted series of method calls) is being closed. If the client program then tries to create another statement using the same connection a null pointer exception results because the underlying connection is returning a null, having been closed already. Whether this (the connection returning null instead of throwing another SQL excpetion, which is what you would expect from a closed connection) is what should happen or not is kinda beside the point, it is what is happening, and it is happening because our resource and pooling code decides to destroy the connection when a statement from the connection throws an error. So I guess my question is why do we do this? Is there some convention with jdbc I am unaware of that suggests a connection should become unusuable after a statement obtained from that connection throws an error? Or is there some other good reason we are doing this? If so I can change the code so that any attempted use of the connection in this situation will result in a SQL exception rather than a NPE. If there is no particular reason we are doing this then I will (try) to change the code so we don't do this! Guidence from someone who is familiar with this code would be appreciated, else I am going to bang on by myself and can't guarantee the results :-) Thanks David. -Original Message- From: Peter Fagerlund [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 28, 2001 12:40 PM To: David Maplesden; JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS While pooking around i found and : Uncommented body of deleteObject(pooledObject) - line 71 of org/jboss/resource/connectionmanager.ManagedConnectionPoolFactory.java (it seems this is called when the pool shrinks or is shut down. some test -is shrinking the pool to [0/0/10] and as a effect the next test using the DefaultDS do not have a connection ? ... it should probably create one before trying to create a table ? ...) *** Now when running run-testsuite I have 169 tests running and 1 error 99.41% Success rate - heh ... So the xa test is failing above - We knew that - and disabeling it should render a cool 100% of the 169 tests ! ... /peter_f on 1-11-26 22.54, David Maplesden at [EMAIL PROTECTED] wrote: I have been experiencing a NPE when calling createStatement on a connection obtained from DefaultDS. java.lang.NullPointerException at org.jboss.resource.adapter.jdbc.local.StatementInPool.init(S tatementInPool .java:35) at org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createS tatement(Conne ctionInPool.java:606) This doesn't always occur and I have only noticed it in the last week or so, previously it worked fine. It occurs after a previous statement throws an SQLException. In other words if you
Re: [JBoss-dev] NPE when using DefaultDS
Ok, but the point is that this change broke existing tests in main but not in 2.4 where the change was originally made. You seem to be experiencing another side-effect of the change as the org.jboss.test.cts.test.BmpUnitTestCase failures are SQL exceptions regarding the fact that the connection has been closed. Both issues need to be resolved. - Original Message - From: David Maplesden [EMAIL PROTECTED] To: JBossDev (E-mail) [EMAIL PROTECTED] Sent: Thursday, November 29, 2001 1:44 PM Subject: RE: [JBoss-dev] NPE when using DefaultDS Yes, it was Doug's change that allowed the bug to surface, but on the face of it Doug's change seems a valid one to me, when a managed connection is being deleted from a pool the underlying connection should be closed. I think Doug's change is just showing up some bad handling of the situation that was going unnoticed previously. The problem is being caused by the fact that when the underlying connection is closed the client still has a reference to the connection wrapper, and calling createStatement on this results in a null pointer exception rather than an SQL exception. Of course the other question I was looking for an answer to is why is the connection being closed when a statement throws an exception? Does it need to be? I think there are two things here to fix. David. -Original Message- From: Scott M Stark [mailto:[EMAIL PROTECTED]] Sent: Friday, November 30, 2001 10:41 AM To: JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS The destroy logic was just changed by thedug, so the validity of the changes needs to be justified. I would suggest backing out the change since it seemed to be an unthinking merge from a 2.4 change that may have no relevance to the 3.0 codebase. There were two changes to jbosscx/src/main/org/jboss/resource/connectionmanager/ManagedC onnectionPoolF actory.java This needs to be rolled back to version 1.2 to undo the changes. - Original Message - From: David Maplesden [EMAIL PROTECTED] To: JBossDev (E-mail) [EMAIL PROTECTED] Sent: Thursday, November 29, 2001 12:57 PM Subject: RE: [JBoss-dev] NPE when using DefaultDS Ok, I have done some investigation into this and I think I am understanding the problem, I'm just not too sure of the best solution. I would appreciate the opinion of someone who has worked with this code before. The problem is that when a statement obtained from a given jdbc connection throws a SQL exception the connection (through a rather convoluted series of method calls) is being closed. If the client program then tries to create another statement using the same connection a null pointer exception results because the underlying connection is returning a null, having been closed already. Whether this (the connection returning null instead of throwing another SQL excpetion, which is what you would expect from a closed connection) is what should happen or not is kinda beside the point, it is what is happening, and it is happening because our resource and pooling code decides to destroy the connection when a statement from the connection throws an error. So I guess my question is why do we do this? Is there some convention with jdbc I am unaware of that suggests a connection should become unusuable after a statement obtained from that connection throws an error? Or is there some other good reason we are doing this? If so I can change the code so that any attempted use of the connection in this situation will result in a SQL exception rather than a NPE. If there is no particular reason we are doing this then I will (try) to change the code so we don't do this! Guidence from someone who is familiar with this code would be appreciated, else I am going to bang on by myself and can't guarantee the results :-) Thanks David. -Original Message- From: Peter Fagerlund [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 28, 2001 12:40 PM To: David Maplesden; JBossDev (E-mail) Subject: Re: [JBoss-dev] NPE when using DefaultDS While pooking around i found and : Uncommented body of deleteObject(pooledObject) - line 71 of org/jboss/resource/connectionmanager.ManagedConnectionPoolFactory.java (it seems this is called when the pool shrinks or is shut down. some test -is shrinking the pool to [0/0/10] and as a effect the next test using the DefaultDS do not have a connection ? ... it should probably create one before trying to create a table ? ...) *** Now when running run-testsuite I have 169 tests running and 1 error 99.41% Success rate - heh ... So the xa test is failing above - We knew that - and disabeling it should render a cool 100% of the 169 tests
Re: [JBoss-dev] NPE when using DefaultDS
With David's fix - I just run-testsuite : result 182 tests with 1 error (XA) Thanks /peter_f ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
RE: [JBoss-dev] NPE when using DefaultDS
I got an improvement in the testsuite as well, but not quite that good. I guess we still have platform differences. David -Original Message- From: Peter Fagerlund [mailto:[EMAIL PROTECTED]] Sent: Friday, November 30, 2001 4:51 PM To: David Maplesden Cc: JBossDev Subject: Re: [JBoss-dev] NPE when using DefaultDS With David's fix - I just run-testsuite : result 182 tests with 1 error (XA) Thanks /peter_f ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
Re: [JBoss-dev] NPE when using DefaultDS
on 1-11-30 04.59, David Maplesden at [EMAIL PROTECTED] wrote: I got an improvement in the testsuite as well, but not quite that good. I guess we still have platform differences. ahhh ... how so ? ... Could You check it in with a runtime OS check ? ... /peter_f ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
Re: [JBoss-dev] NPE when using DefaultDS
While pooking around i found and : Uncommented body of deleteObject(pooledObject) - line 71 of org/jboss/resource/connectionmanager.ManagedConnectionPoolFactory.java (it seems this is called when the pool shrinks or is shut down. some test -is shrinking the pool to [0/0/10] and as a effect the next test using the DefaultDS do not have a connection ? ... it should probably create one before trying to create a table ? ...) *** Now when running run-testsuite I have 169 tests running and 1 error 99.41% Success rate - heh ... So the xa test is failing above - We knew that - and disabeling it should render a cool 100% of the 169 tests ! ... /peter_f on 1-11-26 22.54, David Maplesden at [EMAIL PROTECTED] wrote: I have been experiencing a NPE when calling createStatement on a connection obtained from DefaultDS. java.lang.NullPointerException at org.jboss.resource.adapter.jdbc.local.StatementInPool.init(StatementInPool .java:35) at org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createStatement(Conne ctionInPool.java:606) This doesn't always occur and I have only noticed it in the last week or so, previously it worked fine. It occurs after a previous statement throws an SQLException. In other words if you are using the connections from DefaultDS everything is fine until one of your SQL queries causes an SQL exception. After this point you get a NPE every time you try to create another statement from a connection for DefaultDS. I think (though I don't know for sure) that it has been caused by a change to the Object pool code made last week sometime. I hope someone out there can help. Thanks David. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
[JBoss-dev] NPE when using DefaultDS
I have been experiencing a NPE when calling createStatement on a connection obtained from DefaultDS. java.lang.NullPointerException at org.jboss.resource.adapter.jdbc.local.StatementInPool.init(StatementInPool .java:35) at org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createStatement(Conne ctionInPool.java:606) This doesn't always occur and I have only noticed it in the last week or so, previously it worked fine. It occurs after a previous statement throws an SQLException. In other words if you are using the connections from DefaultDS everything is fine until one of your SQL queries causes an SQL exception. After this point you get a NPE every time you try to create another statement from a connection for DefaultDS. I think (though I don't know for sure) that it has been caused by a change to the Object pool code made last week sometime. I hope someone out there can help. Thanks David. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
RE: [JBoss-dev] NPE when using DefaultDS
can we include a test for this as well, it is the kind of thing we don't want to repeat marcf |-Original Message- |From: [EMAIL PROTECTED] |[mailto:[EMAIL PROTECTED]]On Behalf Of David |Maplesden |Sent: Monday, November 26, 2001 4:55 PM |To: JBossDev (E-mail) |Subject: [JBoss-dev] NPE when using DefaultDS | | |I have been experiencing a NPE when calling createStatement on a connection |obtained from DefaultDS. | |java.lang.NullPointerException | at |org.jboss.resource.adapter.jdbc.local.StatementInPool.init(Statem |entInPool |.java:35) | at |org.jboss.resource.adapter.jdbc.local.ConnectionInPool.createStatem |ent(Conne |ctionInPool.java:606) | |This doesn't always occur and I have only noticed it in the last |week or so, |previously it worked fine. | |It occurs after a previous statement throws an SQLException. In |other words |if you are using the connections from DefaultDS everything is fine |until one |of your SQL queries causes an SQL exception. After this point you |get a NPE |every time you try to create another statement from a connection for |DefaultDS. | |I think (though I don't know for sure) that it has been caused by a change |to the Object pool code made last week sometime. | |I hope someone out there can help. | |Thanks |David. | | |--- |Outgoing mail is certified Virus Free. |Checked by AVG anti-virus system (http://www.grisoft.com). |Version: 6.0.298 / Virus Database: 161 - Release Date: 11/13/2001 | | |___ |Jboss-development mailing list |[EMAIL PROTECTED] |https://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
