Google AppEngine and DataNucleus Enhance

Problem:  – Encountered a problem: Unexpected exception

When developing in Google AppEngine with DataNucleus datastore, if you get following error when the DataNucleus is “Enhancing” the data access object (JDO, JPA), then your JDK compile version is not compatible with the DataNucleus. The DataNucleus is not supported for JDK version 1.8 yet. If you change your compile JDK version to 1.7, the problem is resolved.


DataNucleus Enhancer (version 3.1.1) : Enhancement of classes
Encountered a problem: Unexpected exception

java.lang.RuntimeException: Unexpected exception
at com.google.appengine.tools.enhancer.Enhancer.execute(Enhancer.java:76)
at com.google.appengine.tools.enhancer.Enhance.(Enhance.java:71)
at com.google.appengine.tools.enhancer.Enhance.main(Enhance.java:51)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at com.google.appengine.tools.enhancer.Enhancer.execute(Enhancer.java:74)
… 2 more
Caused by: java.lang.IllegalArgumentException
at org.objectweb.asm.ClassReader.(Unknown Source)
at org.objectweb.asm.ClassReader.(Unknown Source)
at org.objectweb.asm.ClassReader.(Unknown Source)
at org.datanucleus.enhancer.asm.ASMClassEnhancer.getClassNameForFileName(ASMClassEnhancer.java:272)
at org.datanucleus.enhancer.DataNucleusEnhancer.getFileMetadataForInput(DataNucleusEnhancer.java:727)
at org.datanucleus.enhancer.DataNucleusEnhancer.enhance(DataNucleusEnhancer.java:525)
at org.datanucleus.enhancer.DataNucleusEnhancer.main(DataNucleusEnhancer.java:1258)
… 7 more