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<p class=MsoNormal><span lang=EN-US>Hi, folks,<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I’m using Drools 5.1, MVEL dialect, JDK
1.6 to build a OLTP system running on tomcat 6.0.28. the runtime environment is
on a cloud virtual and node profile is relatively small. We’ve noticed
below run time exceptions from prod since it’s online from day one which
is impacting transaction processing. However it is happening adhoc-ly. Here I
have 1 question:<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;
mso-list:l0 level1 lfo1'><![if !supportLists]><span lang=EN-US><span
style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><span lang=EN-US>The yellow marked lines are
actually java file compiled from DRL file. Why there is null pointer exception
thrown from </span><span lang=EN-US style='font-size:11.0pt'>org.drools.common.DefaultAgenda.fireActivation</span><span
lang=EN-US style='font-size:11.0pt'>?</span><span lang=EN-US><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>ERROR>2012-02-25
11:42:25,071 com.</span><span lang=EN-US style='font-size:11.0pt'>xxx</span><span
lang=EN-US style='font-size:11.0pt'>.</span><span lang=EN-US style='font-size:
11.0pt'>xxx</span><span lang=EN-US style='font-size:11.0pt'>.</span><span
lang=EN-US style='font-size:11.0pt'>xxx</span><span lang=EN-US
style='font-size:11.0pt'>.</span><span lang=EN-US style='font-size:11.0pt'>xxx</span><span
lang=EN-US style='font-size:11.0pt'>[DefaultQuartzScheduler_Worker-3]: Rules
run time error:</span><span lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>org.drools.runtime.rule.ConsequenceException:
rule: Match</span><span lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'> </span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at
org.drools.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:916)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:845)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at org.drools.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1056)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:733)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:699)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at
org.drools.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:218)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at com. xxx.xxx.xxx.xxx.xxx.xxx.xxx (SessionManager.java:94)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at com. xxx.xxx.xxx.xxx.xxx.xxx.</span><span lang=EN-US style='font-size:11.0pt'>yyy</span><span
lang=EN-US style='font-size:11.0pt'>(SessionManagerJob.java:17)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at org.quartz.core.JobRunShell.run(JobRunShell.java:202)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:525)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>Caused by:
java.lang.NullPointerException</span><span lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at com.xxx.xxx.xxx.xxx.xxx.xxx.xxx(</span><span lang=EN-US style='font-size:
11.0pt'>xxx</span><span lang=EN-US style='font-size:11.0pt'>.java:634)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at com.xxx.xxx.xxx.xxx.xxx.</span><span lang=EN-US style='font-size:11.0pt'>yyy</span><span
lang=EN-US style='font-size:11.0pt'>.</span><span lang=EN-US style='font-size:
11.0pt'>yyy</span><span lang=EN-US style='font-size:11.0pt'>(</span><span
lang=EN-US style='font-size:11.0pt'>yyy</span><span lang=EN-US
style='font-size:11.0pt'>.java:227)</span><span lang=EN-US style='font-size:
11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at com.xxx.xxx.xxx.xxx.xxx.</span><span lang=EN-US style='font-size:11.0pt'>yyy</span><span
lang=EN-US style='font-size:11.0pt'>.</span><span lang=EN-US style='font-size:
11.0pt'>zzz</span><span lang=EN-US style='font-size:11.0pt'>(</span><span
lang=EN-US style='font-size:11.0pt'>zzz</span><span lang=EN-US
style='font-size:11.0pt'>.java:115)</span><span lang=EN-US style='font-size:
11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at com.xxx.xxx.xxx.xxx.xxx.</span><span lang=EN-US style='font-size:11.0pt'>yyy</span><span
lang=EN-US style='font-size:11.0pt'>.</span><span lang=EN-US style='font-size:
11.0pt'>ttt</span><span lang=EN-US style='font-size:11.0pt'>(</span><span
lang=EN-US style='font-size:11.0pt'>ttt</span><span lang=EN-US
style='font-size:11.0pt'>.java:83)</span><span lang=EN-US style='font-size:
11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at com.xxx.xxx.xxx.xxx.xxx.</span><span lang=EN-US style='font-size:11.0pt'>yyy</span><span
lang=EN-US style='font-size:11.0pt'>.</span><span lang=EN-US style='font-size:
11.0pt'>uuu</span><span lang=EN-US style='font-size:11.0pt'>(</span><span
lang=EN-US style='font-size:11.0pt'>uuu</span><span lang=EN-US
style='font-size:11.0pt'>.java:75)</span><span lang=EN-US style='font-size:
11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
<span style='background:yellow;mso-highlight:yellow'>at com. com.xxx.xxx.xxx.xxx.</span></span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>xxx.yyy.vvv</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>(</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>vvv</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>.java:9)</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;background:yellow;
mso-highlight:yellow'> at com. com.xxx.xxx.xxx.xxx.xxx.</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>yyy</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>.</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>www</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>(</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>www</span><span
lang=EN-US style='font-size:11.0pt;background:yellow;mso-highlight:yellow'>.java:28)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
at org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:906)</span><span
lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US style='font-size:11.0pt'>
... 9 more</span><span lang=EN-US style='font-size:11.0pt'><o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Best regards<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Abe<o:p></o:p></span></p>
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