Question

grails run-app from within Eclipse is currently giving me the exception below for my Google App Engine/Grails test application:

Enhancing JDO classes
  [enhance] DataNucleus Enhancer (version 1.1.4) : Enhancement of classes
  [enhance] Jan 24, 2010 5:11:42 AM org.datanucleus.metadata.MetaDataManager loadClasses
  [enhance] SEVERE: Class "org.grails.tomcat.TomcatLoader" was not found in the CLASSPATH. Please check your specification and your CLASSPATH.
  [enhance] org.datanucleus.exceptions.ClassNotResolvedException: Class "org.grails.tomcat.TomcatLoader" was not found in the CLASSPATH. Please check your specification and your CLASSPATH.
  [enhance]     at org.datanucleus.JDOClassLoaderResolver.classForName(JDOClassLoaderResolver.java:250)
  [enhance]     at org.datanucleus.JDOClassLoaderResolver.classForName(JDOClassLoaderResolver.java:415)
  [enhance]     at org.datanucleus.metadata.MetaDataManager.loadClasses(MetaDataManager.java:379)
  [enhance]     at org.datanucleus.enhancer.DataNucleusEnhancer.getFileMetadataForInput(DataNucleusEnhancer.java:743)
  [enhance]     at org.datanucleus.enhancer.DataNucleusEnhancer.enhance(DataNucleusEnhancer.java:545)
  [enhance]     at org.datanucleus.enhancer.DataNucleusEnhancer.main(DataNucleusEnhancer.java:1252)
  [enhance]     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  [enhance]     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
  [enhance]     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
  [enhance]     at java.lang.reflect.Method.invoke(Method.java:597)
  [enhance]     at com.google.appengine.tools.enhancer.Enhancer.execute(Enhancer.java:57)
  [enhance]     at com.google.appengine.tools.enhancer.Enhance.<init>(Enhance.java:60)
  [enhance]     at com.google.appengine.tools.enhancer.Enhance.main(Enhance.java:41)
  [enhance] DataNucleus Enhancer completed with success for 0 classes. Timings : input=487 ms, enhance=0 ms, total=487 ms. Consult the log for full details
  [enhance] DataNucleus Enhancer completed and no classes were enhanced. Consult the log for full details

I get this error after creating a Grails project with Spring Tools Suite (STS) and then installing the app-engine plugin “grails install-plugin app-engine”. Before, I install the app-engine plugin the Grails project runs correctly.

Any ideas?

Answer 1

Have you tried uninstalling the Tomcat plugin? It is installed by default in a new app but looks like it causes issues when you use the GAE plugin.