Extreme Java

Spring team likes big names. One of the biggest is “SimpleRemoteStatelessSessionProxyFactoryBean“. This is not a problem, since I’m not a Fortran programmer. Unfortunatelly, I found two classes with similar names that aren’t type-safe (i.e.: I don’t receive a ClassCast or similar if I swap them): MethodInvokingFactoryBean e MethodInvokingJobDetailFactoryBean. I use the latter a lot, but, after using NB’s autocomplete feature, I selected the former instead:

<bean class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
  <property name="targetObject" ref="cache"/>
  <property name="targetMethod" value="reload"/>
</bean>

Results? NullPointerException:

org.quartz.SchedulerException: Registration of jobs and triggers failed: null [See nested exception: java.lang.NullPointerException]
  at org.springframework.scheduling.quartz.SchedulerFactoryBean.registerJobsAndTriggers(SchedulerFactoryBean.java:861)
  at org.springframework.scheduling.quartz.SchedulerFactoryBean.afterPropertiesSet(SchedulerFactoryBean.java:649)
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1368)
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1334)
  ... 13 more
Caused by: java.lang.NullPointerException
  at org.quartz.core.QuartzScheduler.addJob(QuartzScheduler.java:808)
  at org.quartz.impl.StdScheduler.addJob(StdScheduler.java:288)
  at org.springframework.scheduling.quartz.SchedulerFactoryBean.addJobToScheduler(SchedulerFactoryBean.java:883)
  at org.springframework.scheduling.quartz.SchedulerFactoryBean.addTriggerToScheduler(SchedulerFactoryBean.java:906)
  at org.springframework.scheduling.quartz.SchedulerFactoryBean.registerJobsAndTriggers(SchedulerFactoryBean.java:842)
  ... 16 more

This wasn’t easy to solve, since the NPE wasn’t obvious. Both MIFB and MIJDFB are “factory” instances (they create real instances as needed), and, in this case, no type check was done.

Tags: jobdetail, nullpointerexception, spring

This entry was posted on Monday, March 16th, 2009 at 12:39 pm and is filed under Java SE. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.