Jared:
For new(furture) version we have mechanism to deal with old version nodes. look
InternalDistributedMember class's function (fromDataPre_GFE_7_1_0_0). You can
use this mechanism to deal with older version.
-Hitesh
From: Jared Stewart <jstew...@pivotal.io>
To: dev@geode.apache.org
Sent: Thursday, January 12, 2017 10:52 AM
Subject: Strategy for changing fields in a class serialized with PDX
Cluster configuration [1] is currently serialized with PDX and stored in an
internal region that is replicated on all Locators. I would like to change the
Configuration class from having a Set<String> jarNames to having a Map<String,
byte[]> jarNamesToJarBytes. However, this would create a problem when a
Locator running the new version of the software tries to deserialize an
instance of the previous version of the Configuration class.
Basically, inside Configuration’s fromData() method, I would like to determine
whether the serialized instance came from a version of the class with a Set or
a version of the class with a Map. However, I don’t see methods in
DataSerializer to check for the existence of a particular field name or field
type. Does anyone know of a strategy that has been used in the past to make
these sort of changes?
Thank you,
Jared
[1] org.apache.geode.management.internal.configuration.domain.Configuration
