Cryptic exception on use groovy-based code: java.lang.ClassCastException: class java.util.LinkedHashMap cannot be cast to class java.util.Iterator (java.util.LinkedHashMap and java.util.Iterator are in module java.base of loader 'bootstrap') at org.codehaus.groovy.runtime.dgm$834.invoke(Unknown Source)

[Hubbitus]

From https://gitlab.com/unidata-community/addressmaster/-/issues/5

Really it looks very strange to me and project very well work in container. But running in gretty I got very strange stacktrace:

SEVERE: Exception sending context initialized event to listener instance of class [com.taskdata.addressmaster.server.JulToSlf4jConfigurerInContextLoaderListener]
java.lang.ExceptionInInitializerError
        at com.taskdata.addressmaster.server.JulToSlf4jConfigurerInContextLoaderListener.contextInitialized(JulToSlf4jConfigurerInContextLoaderListener.java:46)
        at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4690)
        at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5151)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
        at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384)
        at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
        at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140)
        at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909)
        at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
        at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384)
        at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
        at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140)
        at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909)
        at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
        at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
        at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
        at org.apache.catalina.startup.Tomcat.start(Tomcat.java:468)
        at org.apache.catalina.startup.Tomcat$start$1.call(Unknown Source)
        at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:47)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:115)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:119)
        at org.akhikhl.gretty.TomcatServerManager.startServer(TomcatServerManager.groovy:52)
        at org.akhikhl.gretty.ServerManager$startServer$0.call(Unknown Source)
        at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:47)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:115)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:127)
        at org.akhikhl.gretty.Runner.run(Runner.groovy:129)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:564)
        at org.codehaus.groovy.runtime.callsite.PlainObjectMetaMethodSite.doInvoke(PlainObjectMetaMethodSite.java:43)
        at org.codehaus.groovy.runtime.callsite.PogoMetaMethodSite$PogoCachedMethodSiteNoUnwrapNoCoerce.invoke(PogoMetaMethodSite.java:190)
        at org.codehaus.groovy.runtime.callsite.PogoMetaMethodSite.call(PogoMetaMethodSite.java:70)
        at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:47)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:115)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:119)
        at org.akhikhl.gretty.Runner.main(Runner.groovy:54)
Caused by: java.lang.ClassCastException: class java.util.LinkedHashMap cannot be cast to class java.util.Iterator (java.util.LinkedHashMap and java.util.Iterator are in module java.base of loader 'bootstrap')
        at org.codehaus.groovy.runtime.dgm$834.invoke(Unknown Source)
        at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite$PojoMetaMethodSiteNoUnwrapNoCoerce.invoke(PojoMetaMethodSite.java:247)
        at org.codehaus.groovy.runtime.callsite.PojoMetaMethodSite.call(PojoMetaMethodSite.java:56)
        at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:47)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:125)
        at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:139)
        at info.hubbitus.utils.bench.ProgressLogger.<clinit>(ProgressLogger.groovy:98)
        ... 46 more

Step to reproduce

For easy reproduce and do not require start databases I have prepared branch #5-gretty-bug-reproduce, just checkout it and as usual run:

./gradlew farmRunDebug

[aindlq]

can you try, as a workaround, to define your farm config explicitly?

[Hubbitus]

Sorry, what you meant under "define your farm config explicitly"?

That already explicitly defined.

[aindlq]

What you linked to is generic gretty config.

Multiple web-apps feature works out-of-the-box in configureless mode, although it is fully configurable/customizable.

https://gretty-gradle-plugin.github.io/gretty-doc/Multiple-web-apps-introduction.html

My guess is something is wrong with configureless mode. Can you try define farm explicitly as documented here - https://gretty-gradle-plugin.github.io/gretty-doc/Farm-web-app-list.html

[aindlq]

Example - https://github.com/gretty-gradle-plugin/gretty/blob/master/integrationTests/farm/MyWebApp/build.gradle#L12

[Hubbitus]

Are you speak about something like https://gitlab.com/unidata-community/addressmaster/-/merge_requests/4/diffs?commit_id=8c5a87f499f5dccc52543b88dc29fbbf78ae0afb#a5feec40b7a05be26caacdbfc454d31ce0825448_124_126 ?

I think it is not change way I need run it (./gradlew farmRunDebug)?
Then it looks like change nothing.

[aindlq]

Hm, apparently you have only one webapp, right? So maybe I'm missing something, but then why are you using farm* tasks if you have only one webapp?

[Hubbitus]

./gradlew appRunDebug changes nothing if you speak about that.