[JENKINS-18775] [XStream] ConcurrentModificationException from DefaultConverterLookup

[jenkins-infra-bot]

A user reported a hung Jenkins instance displaying an error:

org.jvnet.hudson.reactor.ReactorException: java.lang.Error: java.lang.reflect.InvocationTargetException 
	at org.jvnet.hudson.reactor.Reactor.execute(Reactor.java:246) 
	at jenkins.InitReactorRunner.run(InitReactorRunner.java:43) 
	at jenkins.model.Jenkins.executeReactor(Jenkins.java:904) 
	at jenkins.model.Jenkins.(Jenkins.java:804) 
	at hudson.model.Hudson.(Hudson.java:81) 
	at hudson.model.Hudson.(Hudson.java:77) 
	at hudson.WebAppMain$2.run(WebAppMain.java:214) 
Caused by: java.lang.Error: java.lang.reflect.InvocationTargetException 
	at hudson.init.InitializerFinder.invoke(InitializerFinder.java:124) 
	at hudson.init.InitializerFinder$TaskImpl.run(InitializerFinder.java:184) 
	at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:259) 
	at jenkins.model.Jenkins$7.runTask(Jenkins.java:893) 
	at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:187) 
	at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:94) 
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) 
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) 
	at java.lang.Thread.run(Thread.java:722) 
Caused by: java.lang.reflect.InvocationTargetException 
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
	at java.lang.reflect.Method.invoke(Method.java:601) 
	at hudson.init.InitializerFinder.invoke(InitializerFinder.java:120) 
... 8 more 
Caused by: java.util.ConcurrentModificationException 
	at java.util.TreeMap$PrivateEntryIterator.nextEntry(TreeMap.java:1115) 
	at java.util.TreeMap$KeyIterator.next(TreeMap.java:1169) 
	at com.thoughtworks.xstream.core.util.PrioritizedList$PrioritizedItemIterator.next(PrioritizedList.java:91) 
	at com.thoughtworks.xstream.core.DefaultConverterLookup.lookupConverterForType(DefaultConverterLookup.java:55) 
	at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:56)

Seems that DefaultConverterLookup is failing to synchronize access to its converters field; probably another thread was calling registerConverter in the middle of this loop.

---

Originally reported by jglick, imported from: [XStream] ConcurrentModificationException from DefaultConverterLookup

• assignee: jglick
• status: Resolved
• priority: Major
• component(s): core
• label(s): 1.509.4-fixed, threads, xstream
• resolution: Fixed
• resolved: 2013-08-26T15:24:57+00:00
• votes: 0
• watchers: 4
• imported: 2025-11-24

Raw content of original issue

A user reported a hung Jenkins instance displaying an error:


org.jvnet.hudson.reactor.ReactorException: java.lang.Error: java.lang.reflect.InvocationTargetException 
	at org.jvnet.hudson.reactor.Reactor.execute(Reactor.java:246) 
	at jenkins.InitReactorRunner.run(InitReactorRunner.java:43) 
	at jenkins.model.Jenkins.executeReactor(Jenkins.java:904) 
	at jenkins.model.Jenkins.<init>(Jenkins.java:804) 
	at hudson.model.Hudson.<init>(Hudson.java:81) 
	at hudson.model.Hudson.<init>(Hudson.java:77) 
	at hudson.WebAppMain$2.run(WebAppMain.java:214) 
Caused by: java.lang.Error: java.lang.reflect.InvocationTargetException 
	at hudson.init.InitializerFinder.invoke(InitializerFinder.java:124) 
	at hudson.init.InitializerFinder$TaskImpl.run(InitializerFinder.java:184) 
	at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:259) 
	at jenkins.model.Jenkins$7.runTask(Jenkins.java:893) 
	at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:187) 
	at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:94) 
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) 
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) 
	at java.lang.Thread.run(Thread.java:722) 
Caused by: java.lang.reflect.InvocationTargetException 
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
	at java.lang.reflect.Method.invoke(Method.java:601) 
	at hudson.init.InitializerFinder.invoke(InitializerFinder.java:120) 
... 8 more 
Caused by: java.util.ConcurrentModificationException 
	at java.util.TreeMap$PrivateEntryIterator.nextEntry(TreeMap.java:1115) 
	at java.util.TreeMap$KeyIterator.next(TreeMap.java:1169) 
	at com.thoughtworks.xstream.core.util.PrioritizedList$PrioritizedItemIterator.next(PrioritizedList.java:91) 
	at com.thoughtworks.xstream.core.DefaultConverterLookup.lookupConverterForType(DefaultConverterLookup.java:55) 
	at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:56)


Seems that DefaultConverterLookup is failing to synchronize access to its converters field; probably another thread was calling registerConverter in the middle of this loop.

• environment: 1.516; JDK 7u10; Linux

[jenkins-infra-bot]

jglick:

• Original comment link
• Raw content of original comment:

  Upstream: http://jira.codehaus.org/browse/XSTR-744
  

Upstream: http://jira.codehaus.org/browse/XSTR-744

[jenkins-infra-bot]

scm_issue_link:

• Original comment link
• Raw content of original comment:

  Code changed in jenkins
  User: Jesse Glick
  Path:
   xstream/src/java/com/thoughtworks/xstream/core/DefaultConverterLookup.java
  http://jenkins-ci.org/commit/xstream/f3cd8709b1bb640109ddd60daebe7d69bdb719e1
  Log:
    JENKINS-18775 It is necessary to synchronize access to converters, not just typeToConverterMap.
  
  
  

Code changed in jenkins
User: Jesse Glick
Path:
xstream/src/java/com/thoughtworks/xstream/core/DefaultConverterLookup.java
http://jenkins-ci.org/commit/xstream/f3cd8709b1bb640109ddd60daebe7d69bdb719e1
Log:
JENKINS-18775 It is necessary to synchronize access to converters, not just typeToConverterMap.

[jenkins-infra-bot]

scm_issue_link:

• Original comment link
• Raw content of original comment:

  Code changed in jenkins
  User: Jesse Glick
  Path:
   core/pom.xml
  http://jenkins-ci.org/commit/jenkins/89c94dda875fba273d22451c540c2ad9e4ac0197
  Log:
    [FIXED JENKINS-18775] Integrated XStream 1.4.4-jenkins-4 with attempted fix for race condition.
  
  
  

Code changed in jenkins
User: Jesse Glick
Path:
core/pom.xml
http://jenkins-ci.org/commit/jenkins/89c94dda875fba273d22451c540c2ad9e4ac0197
Log:
[FIXED JENKINS-18775] Integrated XStream 1.4.4-jenkins-4 with attempted fix for race condition.

[jenkins-infra-bot]

dogfood:

• Original comment link
• Raw content of original comment:

  Integrated in  jenkins_main_trunk #2831
       [FIXED JENKINS-18775] Integrated XStream 1.4.4-jenkins-4 with attempted fix for race condition. (Revision 89c94dda875fba273d22451c540c2ad9e4ac0197)
  
       Result = SUCCESS
  Jesse Glick : 89c94dda875fba273d22451c540c2ad9e4ac0197
  Files : 
  
  	
  core/pom.xml
  
  
  

Integrated in jenkins_main_trunk #2831
[FIXED JENKINS-18775] Integrated XStream 1.4.4-jenkins-4 with attempted fix for race condition. (Revision 89c94dd)

Result = SUCCESS
Jesse Glick : 89c94dda875fba273d22451c540c2ad9e4ac0197
Files :

• core/pom.xml

[jenkins-infra-bot]

scm_issue_link:

• Original comment link
• Raw content of original comment:

  Code changed in jenkins
  User: Jesse Glick
  Path:
   changelog.html
  http://jenkins-ci.org/commit/jenkins/d3fa3bc906c7cb88c267f36b8eba1150435f9aaf
  Log:
    JENKINS-18775 JENKINS-17248 Noting.
  
  
  

Code changed in jenkins
User: Jesse Glick
Path:
changelog.html
http://jenkins-ci.org/commit/jenkins/d3fa3bc906c7cb88c267f36b8eba1150435f9aaf
Log:
JENKINS-18775 JENKINS-17248 Noting.

[jenkins-infra-bot]

dogfood:

• Original comment link
• Raw content of original comment:

  Integrated in  jenkins_main_trunk #2834
       JENKINS-18775 JENKINS-17248 Noting. (Revision d3fa3bc906c7cb88c267f36b8eba1150435f9aaf)
  
       Result = UNSTABLE
  Jesse Glick : d3fa3bc906c7cb88c267f36b8eba1150435f9aaf
  Files : 
  
  	
  changelog.html
  
  
  

Integrated in jenkins_main_trunk #2834
JENKINS-18775 JENKINS-17248 Noting. (Revision d3fa3bc)

Result = UNSTABLE
Jesse Glick : d3fa3bc906c7cb88c267f36b8eba1150435f9aaf
Files :

• changelog.html

[jenkins-infra-bot]

scm_issue_link:

• Original comment link
• Raw content of original comment:

  Code changed in jenkins
  User: Jesse Glick
  Path:
   core/src/main/java/hudson/util/XStream2.java
  http://jenkins-ci.org/commit/jenkins/1d20c524e14353aa2c047586a300180d1cdf15d2
  Log:
    JENKINS-18775 Noting that this usage of XStream is unsupported and could cause future problems.
  
  
  

Code changed in jenkins
User: Jesse Glick
Path:
core/src/main/java/hudson/util/XStream2.java
http://jenkins-ci.org/commit/jenkins/1d20c524e14353aa2c047586a300180d1cdf15d2
Log:
JENKINS-18775 Noting that this usage of XStream is unsupported and could cause future problems.

[jenkins-infra-bot]

dogfood:

• Original comment link
• Raw content of original comment:

  Integrated in  jenkins_main_trunk #2839
       JENKINS-18775 Noting that this usage of XStream is unsupported and could cause future problems. (Revision 1d20c524e14353aa2c047586a300180d1cdf15d2)
  
       Result = SUCCESS
  Jesse Glick : 1d20c524e14353aa2c047586a300180d1cdf15d2
  Files : 
  
  	
  core/src/main/java/hudson/util/XStream2.java
  
  
  

Integrated in jenkins_main_trunk #2839
JENKINS-18775 Noting that this usage of XStream is unsupported and could cause future problems. (Revision 1d20c52)

Result = SUCCESS
Jesse Glick : 1d20c524e14353aa2c047586a300180d1cdf15d2
Files :

• core/src/main/java/hudson/util/XStream2.java

[jenkins-infra-bot]

t_kurki:

• Original comment link
• Raw content of original comment:

  Are you quite sure about the fix in http://jenkins-ci.org/commit/xstream/f3cd8709b1bb640109ddd60daebe7d69bdb719e1 ? 
  
  Just putting synchronized on all the methods fixes the problem, but is a potentially big bottleneck and not necessary, see https://issues.jenkins-ci.org/browse/JENKINS-19561?focusedCommentId=185282&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-185282
  

Are you quite sure about the fix in http://jenkins-ci.org/commit/xstream/f3cd8709b1bb640109ddd60daebe7d69bdb719e1 ?

Just putting synchronized on all the methods fixes the problem, but is a potentially big bottleneck and not necessary, see https://issues.jenkins-ci.org/browse/JENKINS-19561?focusedCommentId=185282&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-185282

[jenkins-infra-bot]

scm_issue_link:

• Original comment link
• Raw content of original comment:

  Code changed in jenkins
  User: Jesse Glick
  Path:
   core/pom.xml
  http://jenkins-ci.org/commit/jenkins/20004f839d3b59920fd8cd608ff33ea691fe1326
  Log:
    [FIXED JENKINS-18775] Integrated XStream 1.4.4-jenkins-4 with attempted fix for race condition.
  
  (cherry picked from commit 89c94dda875fba273d22451c540c2ad9e4ac0197)
  
  
  

Code changed in jenkins
User: Jesse Glick
Path:
core/pom.xml
http://jenkins-ci.org/commit/jenkins/20004f839d3b59920fd8cd608ff33ea691fe1326
Log:
[FIXED JENKINS-18775] Integrated XStream 1.4.4-jenkins-4 with attempted fix for race condition.

(cherry picked from commit 89c94dd)

[jenkins-infra-bot]

[Original is_duplicated_by from Jira: JENKINS-18868]