[WICKET-6644] AbstractPageableView can only be serialized with Java built-in serialization

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 8.3.0
• Fix Version/s: 9.0.0-M1, 8.4.0
• Component/s: wicket-core
• Assignee: Sven Meier
• Reporter: Thomas Heigl
• Created: 10/Mar/19 10:36
• Updated: 13/Mar/19 12:53
• Resolved: 13/Mar/19 11:55

Description

I'm in the progress of replacing FST serialization, that we have used in production for years, with Kryo.

FST is a drop-in replacement for Java's built-in serialization and respects the readObject/writeObject contract. Kryo does not rely on Java serialization at all.

All of Wicket's classes can be serialized with recent versions of Kryo without problems, but when I did some exploratory testing, I noticed that all our pageable lists were empty after deserialization.

After some investigation, I found the root cause of this: WICKET-1323

AbstractPageableView is the only class in Wicket that relies a custom readObject method to correctly restore its state.

I propose to get rid of this method and simply initialize the transient field to a default value of -1 or use a Long instead of a long to represent the cached item count.

Issue Links

• is caused by: WICKET-1323 AbstractPageableView has transient cachedItemCount, but doesn't set it to -1 on deserialization.
• relates to: WICKET-6554 Remove dependency on Java serialization