[jetty-users] java.lang.reflect.InaccessibleObjectException error in web

["Paul B. Henson" <henson@xxxxxxx>]

I run the shibboleth idp under jetty 12, generally very successfully. I 
had a very strange failure today though.

I restarted one of my idp's earlier, which I do all of the time with no 
problems.

Today though immediately after restarting, I started seeing ELException 
errors (which were passed through to clients as a runtime error message 
on their web browser), basically saying that it could not call 
WarningIterator.hasNext() due to a 
java.lang.reflect.InaccessibleObjectException because "module java.base 
does not "opens java.util" to unnamed module @4eb45fec".

The idp uses spring webflow, and that message appears to be referring to 
an expression evaluation in one of the flows:

    <on-start>
        <evaluate 
expression="WarningConditionMap.entrySet().iterator()" 
result="flowScope.WarningIterator" />
    </on-start>

    <decision-state id="CheckIterator">
        <if test="WarningIterator.hasNext()" then="CheckCondition" 
else="proceed" />
    </decision-state>

but I have no idea why all the sudden it couldn't be called? Everything 
I could see about this particular error recommends either "fixing your 
code" or adding the "--add-opens" jvm argument to work around security 
restrictions in the jvm.

Neither of those seems to apply? It's the same code that was always 
running, and after looking at it for a bit and having no idea why it was 
doing that, I restarted it again and the issue went away, so it was the 
same code that was successfully running again.

I guess a solar flare hit a memory DIMM at just the wrong time and 
screwed up some internal jvm state while it was starting? Very weird and 
very disconcerting not knowing why it happened or if it might happen 
again out of the blue at some point…

Any thoughts on what might have happened here? Thanks much…


2024-08-21 16:28:10,012 - 
2620:df:8000:4702:0:2:800d:1bab/node0z14eizolsvyr15dii518s9huc11 - ERROR 
[net.shibbo
leth.idp.profile.interceptor:35] - Uncaught runtime exception
org.springframework.binding.expression.EvaluationException: An 
ELException occurred getting the value for expression 
'WarningIterator.hasNext()' on context [class 
org.springframework.webflow.engine.impl.RequestControlContextImpl]
        at 
org.springframework.binding.expression.spel.SpringELExpression.getValue(SpringELExpression.java:104)
Caused by: org.springframework.expression.spel.SpelEvaluationException: 
EL1029E: A problem occurred when trying to execute method 'hasNext' on 
object of type 'java.util.LinkedHashMap$LinkedEntryIterator': 'Problem 
invoking method: public final boolean 
java.util.LinkedHashMap$LinkedHashIterator.hasNext()'
        at 
org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:159)
Caused by: org.springframework.expression.AccessException: Problem 
invoking method: public final boolean 
java.util.LinkedHashMap$LinkedHashIterator.hasNext()
        at 
org.springframework.expression.spel.support.ReflectiveMethodExecutor.execute(ReflectiveMethodExecutor.java:146)
Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make 
public final boolean 
java.util.LinkedHashMap$LinkedHashIterator.hasNext() accessible: module 
java.base does not "opens java.util" to unnamed module @4eb45fec
        at 
java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)