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Posted to issues@commons.apache.org by "Gary D. Gregory (Created) (JIRA)" <ji...@apache.org> on 2011/10/17 03:50:11 UTC
[jira] [Created] (POOL-191) ConcurrentModificationException in
GenericObjectPool LinkedList
ConcurrentModificationException in GenericObjectPool LinkedList
---------------------------------------------------------------
Key: POOL-191
URL: https://issues.apache.org/jira/browse/POOL-191
Project: Commons Pool
Issue Type: Bug
Affects Versions: 1.5.6
Environment: Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
Maven home: C:\Java\apache-maven-3.0.3\bin\..
Java version: 1.6.0_24, vendor: Sun Microsystems Inc.
Java home: C:\Program Files\Java\jdk1.6.0_24\jre
Default locale: en_US, platform encoding: Cp1252
OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
Reporter: Gary D. Gregory
{noformat}
java.util.ConcurrentModificationException
at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
at java.util.LinkedList$ListItr.next(LinkedList.java:696)
at java.util.AbstractCollection.toString(AbstractCollection.java:421)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuffer.append(StringBuffer.java:219)
at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuffer.append(StringBuffer.java:219)
at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuilder.append(StringBuilder.java:115)
at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
{noformat}
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[jira] [Commented] (POOL-191) ConcurrentModificationException in
GenericObjectPool LinkedList
Posted by "Phil Steitz (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/POOL-191?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13128677#comment-13128677 ]
Phil Steitz commented on POOL-191:
----------------------------------
Having dug a little bit into the lang code, I am inclined to bounce this back to [lang]. At the very least, the various private collection traversal thingies should come with warning labels. They should *not* be used in concurrent applications and the javadoc should indicate that. There do not appear to be any guards to prevent exactly this kind of exception, when the code breaks access protection and then ends up throwing CoMod exceptions because private collections are being modified while iterated. Other than the lack of a threadsafe toString, I don't see a [pool] bug here.
> ConcurrentModificationException in GenericObjectPool LinkedList
> ---------------------------------------------------------------
>
> Key: POOL-191
> URL: https://issues.apache.org/jira/browse/POOL-191
> Project: Commons Pool
> Issue Type: Bug
> Affects Versions: 1.5.6
> Environment: Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
> Maven home: C:\Java\apache-maven-3.0.3\bin\..
> Java version: 1.6.0_24, vendor: Sun Microsystems Inc.
> Java home: C:\Program Files\Java\jdk1.6.0_24\jre
> Default locale: en_US, platform encoding: Cp1252
> OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
> Reporter: Gary D. Gregory
>
> It is possible to get a {{ConcurrentModificationException}} in a {{LinkedList}} from a {{GenericObjectPool}}.
> This happens when I call {{ReflectionToStringBuilder.toString(this)}} from a subclass of {{GenericObjectPool}}. My guess is that it would happen with just {{ReflectionToStringBuilder.toString(gop)}}. IOW, subclassing does not have anything to do with it I would venture.
> For example, in this stack trace {{JmsSessionPool}} is a subclass of {{GenericObjectPool}}.
> {noformat}
> java.util.ConcurrentModificationException
> at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
> at java.util.LinkedList$ListItr.next(LinkedList.java:696)
> at java.util.AbstractCollection.toString(AbstractCollection.java:421)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuilder.append(StringBuilder.java:115)
> at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
> at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
> at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
> at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
> at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
> at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
> {noformat}
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[jira] [Commented] (POOL-191) ConcurrentModificationException in
GenericObjectPool LinkedList
Posted by "Phil Steitz (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/POOL-191?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13128631#comment-13128631 ]
Phil Steitz commented on POOL-191:
----------------------------------
I forgot that the allocation queue is a LinkedList, so in theory the exception could be coming from there. I would strongly recommend against trying to dump the contents of that field while the pool is running. I don't know how the reflection tostring builder stuff above works, but I would not recommend using reflection to circumvent visibility with classes such as GOP that rely on synchronization and limiting visibility to protect data structures. It would be better to code a threadsafe toString directly if that is what you need.
> ConcurrentModificationException in GenericObjectPool LinkedList
> ---------------------------------------------------------------
>
> Key: POOL-191
> URL: https://issues.apache.org/jira/browse/POOL-191
> Project: Commons Pool
> Issue Type: Bug
> Affects Versions: 1.5.6
> Environment: Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
> Maven home: C:\Java\apache-maven-3.0.3\bin\..
> Java version: 1.6.0_24, vendor: Sun Microsystems Inc.
> Java home: C:\Program Files\Java\jdk1.6.0_24\jre
> Default locale: en_US, platform encoding: Cp1252
> OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
> Reporter: Gary D. Gregory
>
> It is possible to get a {{ConcurrentModificationException}} in a {{LinkedList}} from a {{GenericObjectPool}}.
> This happens when I call {{ReflectionToStringBuilder.toString(this)}} from a subclass of {{GenericObjectPool}}. My guess is that it would happen with just {{ReflectionToStringBuilder.toString(gop)}}. IOW, subclassing does not have anything to do with it I would venture.
> For example, in this stack trace {{JmsSessionPool}} is a subclass of {{GenericObjectPool}}.
> {noformat}
> java.util.ConcurrentModificationException
> at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
> at java.util.LinkedList$ListItr.next(LinkedList.java:696)
> at java.util.AbstractCollection.toString(AbstractCollection.java:421)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuilder.append(StringBuilder.java:115)
> at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
> at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
> at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
> at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
> at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
> at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
> {noformat}
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[jira] [Commented] (POOL-191) ConcurrentModificationException in
GenericObjectPool LinkedList
Posted by "Gary D. Gregory (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/POOL-191?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13128810#comment-13128810 ]
Gary D. Gregory commented on POOL-191:
--------------------------------------
Ok, that all makes sense. Thank you Phil. I'll move the discussion to [lang].
> ConcurrentModificationException in GenericObjectPool LinkedList
> ---------------------------------------------------------------
>
> Key: POOL-191
> URL: https://issues.apache.org/jira/browse/POOL-191
> Project: Commons Pool
> Issue Type: Bug
> Affects Versions: 1.5.6
> Environment: Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
> Maven home: C:\Java\apache-maven-3.0.3\bin\..
> Java version: 1.6.0_24, vendor: Sun Microsystems Inc.
> Java home: C:\Program Files\Java\jdk1.6.0_24\jre
> Default locale: en_US, platform encoding: Cp1252
> OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
> Reporter: Gary D. Gregory
>
> It is possible to get a {{ConcurrentModificationException}} in a {{LinkedList}} from a {{GenericObjectPool}}.
> This happens when I call {{ReflectionToStringBuilder.toString(this)}} from a subclass of {{GenericObjectPool}}. My guess is that it would happen with just {{ReflectionToStringBuilder.toString(gop)}}. IOW, subclassing does not have anything to do with it I would venture.
> For example, in this stack trace {{JmsSessionPool}} is a subclass of {{GenericObjectPool}}.
> {noformat}
> java.util.ConcurrentModificationException
> at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
> at java.util.LinkedList$ListItr.next(LinkedList.java:696)
> at java.util.AbstractCollection.toString(AbstractCollection.java:421)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuilder.append(StringBuilder.java:115)
> at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
> at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
> at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
> at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
> at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
> at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
> {noformat}
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[jira] [Commented] (POOL-191) ConcurrentModificationException in
GenericObjectPool LinkedList
Posted by "Gary D. Gregory (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/POOL-191?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13129060#comment-13129060 ]
Gary D. Gregory commented on POOL-191:
--------------------------------------
Created [LANG-762] Handle or document ReflectionToStringBuilder and ToStringBuilder for collections that are not thread safe https://issues.apache.org/jira/browse/LANG-762
> ConcurrentModificationException in GenericObjectPool LinkedList
> ---------------------------------------------------------------
>
> Key: POOL-191
> URL: https://issues.apache.org/jira/browse/POOL-191
> Project: Commons Pool
> Issue Type: Bug
> Affects Versions: 1.5.6
> Environment: Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
> Maven home: C:\Java\apache-maven-3.0.3\bin\..
> Java version: 1.6.0_24, vendor: Sun Microsystems Inc.
> Java home: C:\Program Files\Java\jdk1.6.0_24\jre
> Default locale: en_US, platform encoding: Cp1252
> OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
> Reporter: Gary D. Gregory
>
> It is possible to get a {{ConcurrentModificationException}} in a {{LinkedList}} from a {{GenericObjectPool}}.
> This happens when I call {{ReflectionToStringBuilder.toString(this)}} from a subclass of {{GenericObjectPool}}. My guess is that it would happen with just {{ReflectionToStringBuilder.toString(gop)}}. IOW, subclassing does not have anything to do with it I would venture.
> For example, in this stack trace {{JmsSessionPool}} is a subclass of {{GenericObjectPool}}.
> {noformat}
> java.util.ConcurrentModificationException
> at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
> at java.util.LinkedList$ListItr.next(LinkedList.java:696)
> at java.util.AbstractCollection.toString(AbstractCollection.java:421)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuilder.append(StringBuilder.java:115)
> at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
> at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
> at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
> at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
> at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
> at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
> {noformat}
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[jira] [Closed] (POOL-191) ConcurrentModificationException in
GenericObjectPool LinkedList
Posted by "Gary D. Gregory (Closed) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/POOL-191?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Gary D. Gregory closed POOL-191.
--------------------------------
Resolution: Not A Problem
> ConcurrentModificationException in GenericObjectPool LinkedList
> ---------------------------------------------------------------
>
> Key: POOL-191
> URL: https://issues.apache.org/jira/browse/POOL-191
> Project: Commons Pool
> Issue Type: Bug
> Affects Versions: 1.5.6
> Environment: Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
> Maven home: C:\Java\apache-maven-3.0.3\bin\..
> Java version: 1.6.0_24, vendor: Sun Microsystems Inc.
> Java home: C:\Program Files\Java\jdk1.6.0_24\jre
> Default locale: en_US, platform encoding: Cp1252
> OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
> Reporter: Gary D. Gregory
>
> It is possible to get a {{ConcurrentModificationException}} in a {{LinkedList}} from a {{GenericObjectPool}}.
> This happens when I call {{ReflectionToStringBuilder.toString(this)}} from a subclass of {{GenericObjectPool}}. My guess is that it would happen with just {{ReflectionToStringBuilder.toString(gop)}}. IOW, subclassing does not have anything to do with it I would venture.
> For example, in this stack trace {{JmsSessionPool}} is a subclass of {{GenericObjectPool}}.
> {noformat}
> java.util.ConcurrentModificationException
> at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
> at java.util.LinkedList$ListItr.next(LinkedList.java:696)
> at java.util.AbstractCollection.toString(AbstractCollection.java:421)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuilder.append(StringBuilder.java:115)
> at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
> at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
> at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
> at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
> at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
> at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
> {noformat}
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[jira] [Commented] (POOL-191) ConcurrentModificationException in
GenericObjectPool LinkedList
Posted by "Phil Steitz (Commented) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/POOL-191?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13128618#comment-13128618 ]
Phil Steitz commented on POOL-191:
----------------------------------
How exactly does JmsSessionPool.toString() work? GOP 1.5.6 does not implement toString and it does not expose the backing store, which is a ConcurrentLinkedList (a direct linked list impl stolen from [collections], not a subclass of j.u.LinkedList). My guess would be that you used GOP 1.5.6's package-scoped debugInfo method; but then the top of the trace does not make sense, because it should be ConcurrentLinkedList throwing. In theory, using debugInfo with the relaxed synchronization in borrow/return in 1.5.6 could cause ConcurrentMod exceptions, because while that method is synchronized, borrow and return are not fully synched. I will see if I can make this happen using [performance].
Can you share the relevant bits of the code of the subclass? Obviously a test case against [pool] itself would be best.
> ConcurrentModificationException in GenericObjectPool LinkedList
> ---------------------------------------------------------------
>
> Key: POOL-191
> URL: https://issues.apache.org/jira/browse/POOL-191
> Project: Commons Pool
> Issue Type: Bug
> Affects Versions: 1.5.6
> Environment: Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
> Maven home: C:\Java\apache-maven-3.0.3\bin\..
> Java version: 1.6.0_24, vendor: Sun Microsystems Inc.
> Java home: C:\Program Files\Java\jdk1.6.0_24\jre
> Default locale: en_US, platform encoding: Cp1252
> OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
> Reporter: Gary D. Gregory
>
> It is possible to get a {{ConcurrentModificationException}} in a {{LinkedList}} from a {{GenericObjectPool}}.
> This happens when I call {{ReflectionToStringBuilder.toString(this)}} from a subclass of {{GenericObjectPool}}. My guess is that it would happen with just {{ReflectionToStringBuilder.toString(gop)}}. IOW, subclassing does not have anything to do with it I would venture.
> For example, in this stack trace {{JmsSessionPool}} is a subclass of {{GenericObjectPool}}.
> {noformat}
> java.util.ConcurrentModificationException
> at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
> at java.util.LinkedList$ListItr.next(LinkedList.java:696)
> at java.util.AbstractCollection.toString(AbstractCollection.java:421)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuilder.append(StringBuilder.java:115)
> at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
> at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
> at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
> at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
> at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
> at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
> {noformat}
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[jira] [Updated] (POOL-191) ConcurrentModificationException in
GenericObjectPool LinkedList
Posted by "Gary D. Gregory (Updated) (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/POOL-191?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Gary D. Gregory updated POOL-191:
---------------------------------
Description:
It is possible to get a {{ConcurrentModificationException}} in a {{LinkedList}} from a {{GenericObjectPool}}.
This happens when I call {{ReflectionToStringBuilder.toString(this)}} from a subclass of {{GenericObjectPool}}. My guess is that it would happen with just {{ReflectionToStringBuilder.toString(gop)}}. IOW, subclassing does not have anything to do with it I would venture.
For example, in this stack trace {{JmsSessionPool}} is a subclass of {{GenericObjectPool}}.
{noformat}
java.util.ConcurrentModificationException
at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
at java.util.LinkedList$ListItr.next(LinkedList.java:696)
at java.util.AbstractCollection.toString(AbstractCollection.java:421)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuffer.append(StringBuffer.java:219)
at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuffer.append(StringBuffer.java:219)
at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuilder.append(StringBuilder.java:115)
at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
{noformat}
was:
{noformat}
java.util.ConcurrentModificationException
at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
at java.util.LinkedList$ListItr.next(LinkedList.java:696)
at java.util.AbstractCollection.toString(AbstractCollection.java:421)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuffer.append(StringBuffer.java:219)
at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuffer.append(StringBuffer.java:219)
at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
at java.lang.String.valueOf(String.java:2826)
at java.lang.StringBuilder.append(StringBuilder.java:115)
at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
{noformat}
> ConcurrentModificationException in GenericObjectPool LinkedList
> ---------------------------------------------------------------
>
> Key: POOL-191
> URL: https://issues.apache.org/jira/browse/POOL-191
> Project: Commons Pool
> Issue Type: Bug
> Affects Versions: 1.5.6
> Environment: Apache Maven 3.0.3 (r1075438; 2011-02-28 12:31:09-0500)
> Maven home: C:\Java\apache-maven-3.0.3\bin\..
> Java version: 1.6.0_24, vendor: Sun Microsystems Inc.
> Java home: C:\Program Files\Java\jdk1.6.0_24\jre
> Default locale: en_US, platform encoding: Cp1252
> OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows"
> Reporter: Gary D. Gregory
>
> It is possible to get a {{ConcurrentModificationException}} in a {{LinkedList}} from a {{GenericObjectPool}}.
> This happens when I call {{ReflectionToStringBuilder.toString(this)}} from a subclass of {{GenericObjectPool}}. My guess is that it would happen with just {{ReflectionToStringBuilder.toString(gop)}}. IOW, subclassing does not have anything to do with it I would venture.
> For example, in this stack trace {{JmsSessionPool}} is a subclass of {{GenericObjectPool}}.
> {noformat}
> java.util.ConcurrentModificationException
> at java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:761)
> at java.util.LinkedList$ListItr.next(LinkedList.java:696)
> at java.util.AbstractCollection.toString(AbstractCollection.java:421)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:598)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:473)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:692)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.comm.jms.JmsSessionPool.toString(JmsSessionPool.java:120)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuffer.append(StringBuffer.java:219)
> at org.apache.commons.lang3.builder.ToStringStyle.appendDetail(ToStringStyle.java:586)
> at org.apache.commons.lang3.builder.ToStringStyle.appendInternal(ToStringStyle.java:550)
> at org.apache.commons.lang3.builder.ToStringStyle.append(ToStringStyle.java:436)
> at org.apache.commons.lang3.builder.ToStringBuilder.append(ToStringBuilder.java:848)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.appendFieldsIn(ReflectionToStringBuilder.java:528)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:689)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:288)
> at org.apache.commons.lang3.builder.ReflectionToStringBuilder.toString(ReflectionToStringBuilder.java:119)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:828)
> at com.seagullsw.appinterface.server.comm.BasicCommunicationManager.toString(BasicCommunicationManager.java:817)
> at java.lang.String.valueOf(String.java:2826)
> at java.lang.StringBuilder.append(StringBuilder.java:115)
> at com.seagullsw.appinterface.server.AisHelper.waitForCommuncationManagers(AisHelper.java:217)
> at com.seagullsw.appinterface.server.AisHelper.start(AisHelper.java:136)
> at com.seagullsw.appinterface.server.AisHelper.startFromResource(AisHelper.java:161)
> at com.seagullsw.appinterface.server.AbstractServerJunit4.startServer(AbstractServerJunit4.java:179)
> at com.seagullsw.appinterface.server.comm.jms.AbstractJmsRoundtripMaxConcurrencyTestCase.setUpOnce(AbstractJmsRoundtripMaxConcurrencyTestCase.java:141)
> at com.seagullsw.appinterface.server.comm.jms.ibmmq.JmsRoundtripMaxConcurrency032TestCase.setUpOnce(JmsRoundtripMaxConcurrency032TestCase.java:40)
> {noformat}
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