Gatling 3.7.4 execution issue - ClassNotFoundException

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Alex Michael

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Feb 15, 2022, 2:54:03 AM2/15/22
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Hi Stephane Landelle / Team

I upgraded my Gatling and Maven to the latest version below are the snippet.

<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<!-- <scala.version>2.12.7</scala.version> -->
<encoding>UTF-8</encoding>
<gatling.version>3.7.4</gatling.version>
<gatling-plugin.version>4.1.1</gatling-plugin.version>
<maven-jar-plugin.version>3.2.0</maven-jar-plugin.version>
<scala-maven-plugin.version>4.5.6</scala-maven-plugin.version>
</properties>


But when triggering the mvn command from IDE, its failing to find the Classes
mvn command -- ./mvnw clean gatling:test -Dgatling.simulationClass=com.sampleproject.ProjectStoreSimulation

[ERROR] i.g.a.Gatling$ - Run crashed
java.lang.ClassNotFoundException: com.sampleproject.ProjectStoreSimulation
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
....
...
Wrapped by: java.lang.IllegalArgumentException: User defined Simulation class com.sampleproject.ProjectStoreSimulation could not be loaded
at io.gatling.app.Selection$Selector.findUserDefinedSimulationInClassloader$1(Selection.scala:87)
at io.gatling.app.Selection$Selector.$anonfun$singleSimulationFromConfig$4(Selection.scala:91)
...
...
...

Caused by: java.lang.IllegalArgumentException: User defined Simulation class com.sampleproject.ProjectStoreSimulation could not be loaded
at io.gatling.app.Selection$Selector.findUserDefinedSimulationInClassloader$1(Selection.scala:87)
at io.gatling.app.Selection$Selector.$anonfun$singleSimulationFromConfig$4(Selection.scala:91)
at scala.Option.orElse(Option.scala:477)

Caused by: java.lang.ClassNotFoundException: com.sampleproject.ProjectStoreSimulation
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

[ERROR] Failed to execute goal io.gatling:gatling-maven-plugin:4.1.1:test (default-cli) on project upgrade-store-test: Gatling failed. Process exited with an error: 255 (Exit value: 255) -> [Help 1]


But when I run the Engine directly the script executes perfectly it only fails with MVN command.

--Alex Michael Raj J


Stéphane LANDELLE

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Feb 15, 2022, 3:04:16 AM2/15/22
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Hi,

As requested in this group's terms, please:
  • Provide a Short, Self Contained, Correct (Compilable), Example (see http://sscce.org/)
--

Stéphane Landelle

Chief Technical Officer

   

slan...@gatling.io
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Alex Michael

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Feb 15, 2022, 4:16:45 AM2/15/22
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After upgrading my Gatling from 3.0.0 To 3.7.4, the script is failing to execute from mvn commandLine with the below error. Below are the error message I see as part of mvn execution. 
Need help in understanding the reason for the issue.


ERROR] i.g.a.Gatling$ - Run crashed
java.lang.ClassNotFoundException: com.sampleproject.ProjectStoreSimulation
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
....
...
Wrapped by: java.lang.IllegalArgumentException: User defined Simulation class com.sampleproject.ProjectStoreSimulation could not be loaded
at io.gatling.app.Selection$Selector.findUserDefinedSimulationInClassloader$1(Selection.scala:87)
at io.gatling.app.Selection$Selector.$anonfun$singleSimulationFromConfig$4(Selection.scala:91)
...
...
...

Caused by: java.lang.IllegalArgumentException: User defined Simulation class com.sampleproject.ProjectStoreSimulation could not be loaded
at io.gatling.app.Selection$Selector.findUserDefinedSimulationInClassloader$1(Selection.scala:87)
at io.gatling.app.Selection$Selector.$anonfun$singleSimulationFromConfig$4(Selection.scala:91)
at scala.Option.orElse(Option.scala:477)

Caused by: java.lang.ClassNotFoundException: com.sampleproject.ProjectStoreSimulation
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

[ERROR] Failed to execute goal io.gatling:gatling-maven-plugin:4.1.1:test (default-cli) on project upgrade-store-test: Gatling failed. Process exited with an error: 255 (Exit value: 255) -> [Help 1]

--Alex

Stéphane LANDELLE

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Feb 15, 2022, 4:17:30 AM2/15/22
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Please provide a sample project!

--

Stéphane Landelle

Chief Technical Officer

   

slan...@gatling.io
gatling.io
   
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Alex Michael

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Feb 15, 2022, 7:37:54 AM2/15/22
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Hi Stephane,
Attached the sample project.
Execution Procedure to replicate the issue:
-> After importing the project re-build the project
-> run the command ./mvnw clean gatling:test -Dgatling.simulationClass=computerDatabase.BasicSimulation on mac Intellij terminal
should be able to replicate the below error
[INFO] --- gatling-maven-plugin:4.1.1:test (default-cli) @ gatling-maven-plugin-demo-scala ---
16:16:27.631 [ERROR] i.g.a.Gatling$ - Run crashed
java.lang.NoClassDefFoundError: computerDatabase/BasicSimulation (wrong name: computerdatabase/BasicSimulation)
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:468)
        at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:362)

        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:264)
        at io.gatling.app.Selection$Selector.$anonfun$singleSimulationFromConfig$2(Selection.scala:76)
        at scala.util.Try$.a


Thankyou,
--Alex 

Stéphane LANDELLE

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Feb 15, 2022, 8:08:23 AM2/15/22
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There's no attachment.
The best way is to publish your project on GitHub.

Regards,

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Stéphane Landelle

Chief Technical Officer

   

slan...@gatling.io
gatling.io
   
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Alex Michael

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Feb 15, 2022, 8:20:59 AM2/15/22
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Hi Stephane,
Unable to attach the project in Google-groups. So I have provided access to slan...@gatling.io for the below link.

--Alex

On Tuesday, February 15, 2022 at 12:04:16 PM UTC+4 Stéphane Landelle wrote:

Stéphane LANDELLE

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Feb 15, 2022, 8:23:54 AM2/15/22
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You have a typo:

-Dgatling.simulationClass=computerDatabase.BasicSimulation

It's computerdatabase in minor case

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Stéphane Landelle

Chief Technical Officer

   

slan...@gatling.io
gatling.io
   
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Alex Michael

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Feb 15, 2022, 8:49:46 AM2/15/22
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Hi Stephane,
My bad.. I have uploaded the new version and uploaded new project.

[INFO] --- gatling-maven-plugin:4.1.1:test (default-cli) @ gatling-maven-plugin-demo-scala ---
17:43:49.034 [ERROR] i.g.a.Gatling$ - Run crashed
java.lang.ClassNotFoundException: computerdatabase.BasicSimulation

        at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:264)
        at io.gatling.app.Selection$Selector.$anonfun$singleSimulationFromConfig$2(Selection.scala:76)
        at scala.util.Try$.apply(Try.scala:210)

--Alex

Stéphane LANDELLE

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Feb 15, 2022, 9:24:01 AM2/15/22
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You haven't properly copied the maven configuration: https://github.com/gatling/gatling-maven-plugin-demo/blob/main/pom.xml#L29-L67

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Stéphane Landelle

Chief Technical Officer

   

slan...@gatling.io
gatling.io
   
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Alex Michael

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Feb 15, 2022, 10:20:52 AM2/15/22
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Thanks a ton Stephane, this fixed my issue.
great, alacritous response! 

--Alex

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