PI12309: Classes that implement writeobject & readobject calling default writeobject during deserialization are not serialized

APAR status

• Closed as program error.

Error description

• This problem occurs in a situation where a class implements the
  writeObject method and that method invokes defaultWriteObject.
  Instead of using the defaultReadObject
  method to deserialize the object, the readObject method uses
  the readFields deserialize the object. For example, the
  java.util.ConcurrentHashMap in the Java 7 JRE behaves in this
  manner.  This can result in objects not being properly
  recreated during deserialization.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  Applications running grids with XIO and     *
  *                  COPY_TO_BYTES enabled.                      *
  ****************************************************************
  * PROBLEM DESCRIPTION: Classes that implement the              *
  *                      writeObject and readObject that should  *
  *                      call defaultWriteObject, but instead    *
  *                      call readFields.                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  This problem occurs in a situation where a class implements
  the writeObject method and that method invokes
  defaultWriteObject, and the readObject method uses the
  readFields approach to deserialize the object instead of
  using the defaultReadObject method.  For example, the
  java.util.ConcurrentHashMap in the Java 7 JRE behaves in this
  manner.  This can result in objects not being
  properly recreated during deserialization.
  

Problem conclusion

• A code change to handle a mixture of serialization formats is
  introduced to address this scenario.
  

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

  WS EXTREME SCAL

• Fixed component ID

  5724X6702

Applicable component levels

• R860 PSY

     UP