Concurrency Problem

[wjn811]

Hi guys,

I am a poor java developer... and I'm on my way pushing myself to learn more.

I met a problem when I use jBPM4.0CR1.

The problem is described as following,

My boss asked me to make a workflow, which mainly contains 2 concurrency flows. And unfortunately, one is contained in another...
That means, a super process has a 'Con1' fork activity. And among the executions under that 'Con1', there is a sub-process, which also contains another fork activity 'Con2'.

Here is jpdls, (concurrency.jpdl.xml & sub_concurrency.jpdl.xml)
I hope you will understand what I am talking about~

concurrency.jpdl.xml

<process name="concurruncy" xmlns="http://jbpm.org/4.0/jpdl">
 <start g="13,103,48,48" name="start1">
 <transition g="-52,-22" name="to fork1" to="fork1"/>
 </start>
 <end g="818,27,48,48" name="end1"/>
 <fork g="100,101,48,48" name="fork1">
 <transition g="-52,-22" name="to task1" to="task1"/>
 <transition name="to task2" to="task2" g="-52,-22"/>
 </fork>
 <task assignee="#{u1}" g="240,145,92,52" name="task1">
 <transition g="-56,-21" name="to Subprocess1" to="Subprocess1"/>
 </task>
 <task assignee="#{u2}" g="223,12,92,52" name="task2">
 <transition g="-49,-22" name="to join2" to="join2"/>
 </task>
 <join g="681,26,48,48" name="join2">
 <transition g="-50,-22" name="to end1" to="end1"/>
 </join>
 <sub-process g="420,139,92,52" name="Subprocess1" sub-process-key="sub_concurrency">
 <parameter-in subvar="u2" var="u2"/>
 <parameter-in subvar="u4" var="u4"/>
 <transition g="-49,-22" name="to join2" to="join2"/>
 </sub-process>
</process>

sub_concurrency.jpdl.xml

<process name="sub_concurrency" xmlns="http://jbpm.org/4.0/jpdl">
 <start g="89,110,48,48" name="start1">
 <transition g="-52,-22" name="to fork1" to="fork1"/>
 </start>
 <end g="596,115,48,48" name="sub_end"/>
 <fork g="200,107,48,48" name="fork1">
 <transition g="-52,-22" name="to task4" to="task4"/>
 <transition name="to task3" to="task3" g="-52,-22"/>
 </fork>
 <task assignee="#{u3}" g="304,60,92,52" name="task3">
 <transition g="-28,-25" name="to sub_join" to="sub_join"/>
 </task>
 <task assignee="#{u4}" g="309,150,92,52" name="task4">
 <transition g="-27,3" name="to sub_join" to="sub_join"/>
 </task>
 <join g="483,113,48,48" name="sub_join">
 <transition g="-36,-25" name="to sub_end" to="sub_end"/>
 </join>
</process>

I'm sorry. I apply these nonsense names on assignees and task names :)

I make a JUnit test to run this work flow.
Then, java exceptions appears,

10:46:30,185 FIN | [Execution] execution[to task4] ends
10:46:30,187 FIN | [Execution] execution[to task3] ends
10:46:30,187 FIN | [ExecuteActivity] executing activity(sub_end)
10:46:30,188 FIN | [Execution] process-instance ends with state ended
10:46:30,203 FIN | [Signal] execution[to task1] signals activity(Subprocess1)
10:46:30,204 WRN | [ProxyWarnLog] Narrowing proxy to class org.jbpm.jpdl.internal.model.JpdlExecution - this operation breaks ==
10:46:30,204 FIN | [ExecuteActivity] execution[to task1] executes activity(join2)
10:46:30,213 FIN | [Execution] execution[to task1] ends
10:46:30,215 FIN | [Execution] execution[to task2] ends
10:46:30,215 FIN | [ExecuteActivity] executing activity(end1)
10:46:30,215 FIN | [Execution] process-instance ends with state ended
10:46:30,228 WRN | [JDBCExceptionReporter] SQL Error: 1451, SQLState: 23000
10:46:30,229 SEV | [JDBCExceptionReporter] Cannot delete or update a parent row: a foreign key constraint fails (`jbpm4db/jbpm4_execution`, CONSTRAINT `FK_EXEC_SUPEREXEC` FOREIGN KEY (`SUPEREXEC_`) REFERENCES `jbpm4_execution` (`DBID_`))
### EXCEPTION ###########################################
10:46:30,229 SEV | [AbstractFlushingEventListener] Could not synchronize database state with session
org.hibernate.exception.ConstraintViolationException: could not delete: [org.jbpm.jpdl.internal.model.JpdlExecution#2]
 at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:94)
 at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
 at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2569)
 at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2725)
 at org.hibernate.action.EntityDeleteAction.execute(EntityDeleteAction.java:97)
 at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:279)
 at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:263)
 at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:172)
 at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321)
 at org.hibernate.event.def.DefaultAutoFlushEventListener.onAutoFlush(DefaultAutoFlushEventListener.java:64)
 at org.hibernate.impl.SessionImpl.autoFlushIfRequired(SessionImpl.java:996)
 at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1141)
 at org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
 at org.hibernate.impl.AbstractQueryImpl.uniqueResult(AbstractQueryImpl.java:835)
 at org.jbpm.pvm.internal.hibernate.DbSessionImpl.findProcessInstanceById(DbSessionImpl.java:175)
 at org.jbpm.pvm.internal.hibernate.DbSessionImpl.deleteProcessInstance(DbSessionImpl.java:225)
 at org.jbpm.pvm.internal.model.ExecutionImpl.end(ExecutionImpl.java:354)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:597)
 at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:197)
 at org.jbpm.pvm.internal.model.ExecutionImpl_$$_javassist_3.end(ExecutionImpl_$$_javassist_3.java)
 at org.jbpm.pvm.internal.model.ExecutionImpl.end(ExecutionImpl.java:364)
 at org.jbpm.jpdl.internal.activity.EndActivity.execute(EndActivity.java:82)
 at org.jbpm.jpdl.internal.activity.EndActivity.execute(EndActivity.java:45)
 at org.jbpm.pvm.internal.model.op.ExecuteActivity.perform(ExecuteActivity.java:60)
 at org.jbpm.pvm.internal.model.ExecutionImpl.performAtomicOperationSync(ExecutionImpl.java:625)
 at org.jbpm.pvm.internal.model.ExecutionImpl.fire(ExecutionImpl.java:535)
 at org.jbpm.pvm.internal.model.ExecutionImpl.take(ExecutionImpl.java:441)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:597)
 at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:197)
 at org.jbpm.pvm.internal.model.ExecutionImpl_$$_javassist_3.take(ExecutionImpl_$$_javassist_3.java)

I find that all the execution has been well finished and inactive executions will be deleted from jbpm4_exection

10:53:39,305 FIN | [ExecuteActivity] execution[to task1] executes activity(join2)
10:53:39,311 FIN | [Execution] execution[to task1] ends
10:53:39,314 FIN | [Execution] execution[to task2] ends
10:53:39,314 FIN | [ExecuteActivity] executing activity(end1)
10:53:39,314 FIN | [Execution] process-instance ends with state ended

But failed because of foreign key constraint. I dont know why...

Do I make the problem clearly described?

Please help me~ Thx!


My mail: [e-mail]
-----------------------------------------------------
And I find that if I add a state activity just after sub-process, which will join together with task2, things go right! Is it a kind of answer?

[wjn811]

It's me again...

I will post data generated by jBPM in MySQL just after exceptions occur

SQL

SELECT * FROM jbpm4_execution\G;

Data in jbpm4_execution

*************************** 1. row ***************************
 DBID_: 1
 CLASS_: jpdl
 DBVERSION_: 1
 ACTIVITYNAME_: NULL
 PROCDEFID_: concurruncy-1
 HASVARS_:
 NAME_: NULL
 KEY_: NULL
 ID_: concurruncy.1
 STATE_: inactive-concurrent-root
SUSPHISTSTATE_: NULL
 PRIORITY_: 0
 HISACTINST_: NULL
 PARENT_: NULL
 INSTANCE_: 1
 SUPEREXEC_: NULL
 SUBPROCINST_: NULL
 PARENT_IDX_: NULL
*************************** 2. row ***************************
 DBID_: 2
 CLASS_: jpdl
 DBVERSION_: 1
 ACTIVITYNAME_: Subprocess1
 PROCDEFID_: concurruncy-1
 HASVARS_:
 NAME_: to task1
 KEY_: NULL
 ID_: concurruncy.1.to task1[0]
 STATE_: active-concurrent
SUSPHISTSTATE_: NULL
 PRIORITY_: 0
 HISACTINST_: 1
 PARENT_: 1
 INSTANCE_: 1
 SUPEREXEC_: NULL
 SUBPROCINST_: 4
 PARENT_IDX_: 0
*************************** 3. row ***************************
 DBID_: 3
 CLASS_: jpdl
 DBVERSION_: 1
 ACTIVITYNAME_: join2
 PROCDEFID_: concurruncy-1
 HASVARS_:
 NAME_: to task2
 KEY_: NULL
 ID_: concurruncy.1.to task2[0]
 STATE_: inactive-join
SUSPHISTSTATE_: NULL
 PRIORITY_: 0
 HISACTINST_: 2
 PARENT_: 1
 INSTANCE_: 1
 SUPEREXEC_: NULL
 SUBPROCINST_: NULL
 PARENT_IDX_: 1
*************************** 4. row ***************************
 DBID_: 4
 CLASS_: jpdl
 DBVERSION_: 1
 ACTIVITYNAME_: NULL
 PROCDEFID_: sub_concurrency-1
 HASVARS_:
 NAME_: NULL
 KEY_: NULL
 ID_: sub_concurrency.4
 STATE_: inactive-concurrent-root
SUSPHISTSTATE_: NULL
 PRIORITY_: 0
 HISACTINST_: NULL
 PARENT_: NULL
 INSTANCE_: 4
 SUPEREXEC_: 2
 SUBPROCINST_: NULL
 PARENT_IDX_: NULL
*************************** 5. row ***************************
 DBID_: 5
 CLASS_: jpdl
 DBVERSION_: 1
 ACTIVITYNAME_: sub_join
 PROCDEFID_: sub_concurrency-1
 HASVARS_:
 NAME_: to task4
 KEY_: NULL
 ID_: sub_concurrency.4.to task4[0]
 STATE_: inactive-join
SUSPHISTSTATE_: NULL
 PRIORITY_: 0
 HISACTINST_: 3
 PARENT_: 4
 INSTANCE_: 4
 SUPEREXEC_: NULL
 SUBPROCINST_: NULL
 PARENT_IDX_: 0
*************************** 6. row ***************************
 DBID_: 6
 CLASS_: jpdl
 DBVERSION_: 0
 ACTIVITYNAME_: task3
 PROCDEFID_: sub_concurrency-1
 HASVARS_:
 NAME_: to task3
 KEY_: NULL
 ID_: sub_concurrency.4.to task3[0]
 STATE_: active-concurrent
SUSPHISTSTATE_: NULL
 PRIORITY_: 0
 HISACTINST_: 4
 PARENT_: 4
 INSTANCE_: 4
 SUPEREXEC_: NULL
 SUBPROCINST_: NULL
 PARENT_IDX_: 1
6 rows in set (0.00 sec)

Look at row 4. Its SUPEREXEC_ refers to row2(DBID_=2)

[kukeltje]

sorry, this is not directed at you peronally but DOES ANYBODY EVER USE SOME KIND OF SEARCH FUNCTIONALITY?

The post below yours is about EXACTELY this same Error

[kukeltje]

See http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4238433#4238433

[wjn811]

hi kukeltje,

very appreciate your replies!

I'm a new one here. And I even don't know JIRA... What a pity!

I go through the topic you have metioned

http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4238433#4238433

If I don't misunderstand that post, changing org.hibernate.dialect can get my problem solved?

However, my org.hibernate.dialect is configured as org.hibernate.dialect.MySQLInnoDBDialect...

<property name="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/jbpm4db</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password">123456</property>
<property name="hibernate.hbm2ddl.auto">update</property>
<property name="hibernate.show.sql">true</property>

<mapping resource="jbpm.repository.hbm.xml" />
<mapping resource="jbpm.execution.hbm.xml" />
<mapping resource="jbpm.history.hbm.xml" />
<mapping resource="jbpm.task.hbm.xml" />
<mapping resource="jbpm.jpdl.hbm.xml" />
<mapping resource="jbpm.identity.hbm.xml" />

So I think my problem is different from that. ?



And the ConstraintViolationException
here is because `FK_EXEC_SUPEREXEC` but not `FK_EXEC_INSTANCE` (Yes, it's due to that I use sub-process. Because if I put these 2 fork flows into One process, one embedded into another, tasks in Inner-Fork-Flow will be created twice)



This time I try to be clever to USE SOME KIND OF SEARCH FUNCTIONALITY (I was stupid enough yesterday~~). I learn Google! hahaha

Fortunately, I find this issue list

https://jira.jboss.org/jira/secure/BrowseVersion.jspa?id=10052&versionId=12313199&showOpenIssuesOnly=true (And I know JIRA! Fortunately again)



And I find this issue JBPM-2303 UNRESOLVED Exception with a process containing a fork/join

You can touch it:https://jira.jboss.org/jira/browse/JBPM-2303

I ran that tests and got exceptions. I think join/fork flow has its own bugs.



I should go to see what happens in jBPM4. I should have enough time to do that. It's my fault.

I really want to know what's wrong with my code, What is the actual reason caused that exception happens. If it is proved to be a bug, I can sleep well tonight~~ hahaha



Please help me again. Thx!

Or I have to wait for jBPM4 released? hahahaha

My e-mail: [e-mail]

[kukeltje]

And maybe this as well

[jbpmjboss11]

Did you find the solution for this issue. I am having the same problem.

Thanks
Yo