Troubleshooting JAXBException in JobRunr Scheduled Task with JDK 17 Spring Boot App deployed in Azure App Service

Question

I'm encountering a JAXBException only when running a scheduled task in development environment with JobRunr on JDK 17 and Spring Boot, deployed on Azure. The issue does not occur when I call the same method through a controller or locally.

**Issue: ** In dev environment, during a JobRunr cron job execution, I face:

javax.xml.bind.JAXBException: Implementation of JAXB-API has not been found on module path or classpath.

**What I've Tried: ** Confirmed JAXB dependencies in pom.xml (using org.glassfish.jaxb:jaxb-runtime:4.0.5).

Printed classpath and ClassLoader details during both controller and cron job execution. Results are identical:

This error arises despite using the same code to create a JAXBContext instance:

try {
    JAXBContext jc = JAXBContext.newInstance(MrwServiceImpl.class);
    LOG.error("JAXBContext: {}", jc);
} catch (JAXBException e) {
    LOG.error("Error al crear JAXBContext", e);
}

While executing locally or from controller:

2024-03-16T12:09:36.688Z ERROR 128 --- [http-nio-80-exec-5] e.a.s.api.service.impl.TestServiceImpl    : JAXBContext: jar:file:/home/site/wwwroot/app.jar!/BOOT-INF/lib/jaxb-impl-4.0.2.jar!/org/glassfish/jaxb/runtime/v2/runtime/JAXBContextImpl.class Build-Id: 4.0.2 - d104f19
Classes known to this context:
  [B
  boolean
  byte
  char
  double
  es.miapp.shippingservices.api.service.impl.TestServiceImpl
  float
  int
  jakarta.activation.DataHandler
  jakarta.xml.bind.JAXBElement
  java.awt.Image
  java.io.File
  java.lang.Boolean
  java.lang.Byte
  java.lang.Character
  java.lang.Class
  java.lang.Double
  java.lang.Float
  java.lang.Integer
  java.lang.Long
  java.lang.Object
  java.lang.Short
  java.lang.String
  java.lang.Void
  java.math.BigDecimal
  java.math.BigInteger
  java.net.URI
  java.net.URL
  java.util.Calendar
  java.util.Date
  java.util.GregorianCalendar
  java.util.UUID
  javax.xml.datatype.Duration
  javax.xml.datatype.XMLGregorianCalendar
  javax.xml.namespace.QName
  javax.xml.transform.Source
  long
  org.glassfish.jaxb.runtime.api.CompositeStructure
  short
  void

ClassPath: /home/site/wwwroot/app.jar:/usr/local/appservice/lib/azure.appservice.jar
Class Loader: org.springframework.boot.loader.LaunchedURLClassLoader

Inspected and logged environment variables and system properties, but no significant differences were found.

Added explicit logging around JAXBContext creation and other JAXB operations.

Checked for potential conflicts in class loading and Spring configurations.

Ran successfully in the local environment against the dev setup.

**Question: ** How can I ensure the correct JAXB implementation is available in the classpath during JobRunr cron executions in a production Azure environment? Are there specific configurations or environment conditions in Azure or JobRunr that could affect class loading differently compared to a local run or controller-invoked method?

Any insights into solving this perplexing behavior will be greatly appreciated!

Answer 1

If you have javax.xml.bind.JAXBException exception and having jaxb-ri 4.x in your classpath, you've mixed jaxb-api and jaxb-ri.

I'm pretty sure your application use jaxb-api 2.x but runtime is 4.x which are incompatible.

Depending of SpringBoot version, you should downgrade jaxb-ri to 2.x (2.3.9) if targeting SpringBoot 2.x or upgrade jaxb-api to 4.x (4.0.2) if targeting SpringBoot 3.x