PH60659: NULLPOINTEREXCEPTION CAN OCCUR IN KERNEL CLASSLOADER

APAR status

• Closed as program error.

Error description

• When loading a Class from the Liberty Kernel ClassLoader, a
  NullPointerException can be seen when there is a file system
  problem causing reading from a jar file to fail. The cause by
  will looking similar to the below stack trace.
  
  java.lang.NullPointerException
  at
  com.ibm.ws.kernel.internal.classloader.JarFileClassLoader.findCl
  ass(JarFileClassLoader.java:165)
  at
  com.ibm.ws.kernel.internal.classloader.BootstrapChildFirstJarCla
  ssloader.loadClass(BootstrapChildFirstJarClassloader.java:92)
  at
  java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:1075)
  at
  org.eclipse.osgi.internal.loader.SystemBundleLoader.findLocalCla
  ss(SystemBundleLoader.java:63)
  at
  org.eclipse.osgi.internal.loader.sources.SingleSourcePackage.loa
  dClass(SingleSourcePackage.java:41)
  at
  org.eclipse.osgi.internal.loader.BundleLoader.findClass0(BundleL
  oader.java:479)
  at
  org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLo
  ader.java:416)
  at
  org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(Mod
  uleClassLoader.java:168)
  at
  java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:1075)
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server Liberty                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: ClassNotFoundException includes a       *
  *                      cause by exception of                   *
  *                      NullPointerException when failing to    *
  *                      load an internal Liberty class.         *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When loading a class from a jar file failed, Liberty
  code incorrectly was throwing a NullPointerException instead
  of indicating that the class was not found by throwing a
  ClassNotFoundException
  

Problem conclusion

• https://github.com/OpenLiberty/open-liberty/issues/27886 is
  the Open Liberty issue for this APAR.  The code was updated
  to no longer generate a NullPointerException when failing to
  read a class from a jar file.
  
  The fix for this APAR is targeted for inclusion in fix pack
  24.0.0.4. For more information, see 'Recommended Updates for
  WebSphere Application Server':
  https://www.ibm.com/support/pages/node/715553
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  WAS LIBERTY COR

• Fixed component ID

  5725L2900

Applicable component levels