PM79151: When you use eXtremeIO (XIO) and COPY_TO_BYTES maps, the readobject method is not invoked.

APAR status

• Closed as program error.

Error description

• In an XIO environment where copyMode=COPY_TO_BYTES, XDF
  serialization is used to serializing the class. When a Java
  class implements the readObject method of the Serializable
  interface, the serialization ignores the Java readObject
  method, which might result in some transient fields not being
  properly populated when a value is deserialized. This fix
  corrects the problem so that the readObject method is invoked.
  
  If you encounter this issue, restart the data grid after
  you apply this fix, since it impacts the serialized data. This
  fix applies to both eXtreme Scale clients and servers.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All WebSphere eXtreme Scale users who       *
  *                  implement XIO and set the copy mode to      *
  *                  COPY_TO_BYTES, with Java classes that       *
  *                  implement the readObject method, but do     *
  *                  implement the writeObject method.           *
  ****************************************************************
  * PROBLEM DESCRIPTION: If a class implements the readObject    *
  *                      method and uses the writeObject         *
  *                      method, XDF does not revert to Java     *
  *                      serialization.                          *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When a Java class implements the Serializable interface method,
  readObject, but does not implement the default writeObject
  method, then Java serialization is not being used. Instead, XDF
  serialization is used, and the readObject method is not
  invoked. Since the readObject method is not invoked by the
  serializer, this behavior usually results in some fields not
  being correctly populated during deserialization.
  

Problem conclusion

• The code was fixed to consider situations where only the
  readObject is defined by the class.
  

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