topic Re: Exception in thread "main" java.lang.NoClassDefFoundError in Talend Studio

Exception in thread "main" java.lang.NoClassDefFoundError

MPT — Fri, 15 Nov 2024 23:00:54 GMT

Edit: We're using Open Studio 7.3.1

We have an issue where we run a job every 10 minutes and it occasionally fails with error

Exception in thread "main" java.lang.NoClassDefFoundError: routines/system/RunStat
- at dataintegration.absencesandholidaystotable_1_2. AbsencesAndHolidaysToTable.<init (AbsencesAndHolidaysToTable.java:267)
- at dataintegration.absencesandholidaystotable_1_2. AbsencesAndHolidaysToTable. main(AbsencesAndHolidaysToTable.java:8925)
Caused by: java.lang.ClassNotFoundException: routines.system.RunStat
- at java.net.URLClassLoader.findClass(Unknown Source)
- at java.lang.ClassLoader.loadClass(Unknown Source)
- at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
- at java.lang.ClassLoader.loadClass(Unknown Source)
- ... 2 more

This is difficult to investigate, because it is seemingly random: the job might work at 10:00, 10:10. 10:20 and at fail at 10:30 with the above error, then work again when executed at 10:40. It does not fail daily, but weekly. Usually only once before working again.

I would image a lock issue should not happen as these are shared libraries right? but we can't figure out what the cause is.

Re: Exception in thread "main" java.lang.NoClassDefFoundError

Anonymous — Fri, 15 Apr 2022 07:22:10 GMT

@Mikael Toivonen, which version of studio are you using? I found one same issue had been reported on Bugtracker, it is better to create a new jira issue for R&D team to investigate it.

Regards

Shong

Re: Exception in thread "main" java.lang.NoClassDefFoundError

DWyman1649849953 — Fri, 15 Apr 2022 10:12:16 GMT

The class is not available in Java Classpath.

You might be running your program using the jar command and class was not defined in the manifest file's ClassPath attribute.

Re: Exception in thread "main" java.lang.NoClassDefFoundError

MPT — Fri, 15 Apr 2022 18:56:44 GMT

We're using Open Studio 7.3.1. I edited that to the opening post too.

Re: Exception in thread "main" java.lang.NoClassDefFoundError

MPT — Fri, 15 Apr 2022 19:03:16 GMT

We have a Windows task scheduler executing this locally deployed job every 10 minutes. The job functions properly for days - until it doesn't. So the class is in the classpath when be build and deploy the job as a self-executable package.

But I will look into if some process of ours might modify the classpath without us realizing it and "sabotaging" the execution of this other job.

Re: Exception in thread "main" java.lang.NoClassDefFoundError

MPT — Wed, 04 May 2022 17:46:56 GMT

I found the issue. When we build jobs, we always use the same target folder (D:\Deployment) for the compiled jobs, even when we built jobs from different projects. That means that all these jobs from different projects shared the D:\Deployment\lib folder. So what happened was that every now and then we re-built a job that altered the D:\Deployment\lib\routines.jar and that broke job #2 that was expecting to find someting from that jar that was not there. As a fix we will build jobs to project-specific sub-folders from now on so that the libraries go to different folders e.g. D:\Deployment\LEGAL\lib and D:\Deployment\HR\lib

Re: Exception in thread "main" java.lang.NoClassDefFoundError

Anonymous — Thu, 05 May 2022 02:28:17 GMT

@Mikael Toivonen, thanks for sharing the solution, it is a good clue.