Make driver-, session- and transaction config serializable.

[mattcasters]

Got stuck with usage of Value in TransactionConfig (for bookmarks) and usage of Optional for fetchSize in SessionConfig.
It's bound to be above my expertise to properly test this.

[michael-simons]

I am in strong favor of this change, as we would gain serializable bookmarks with it, too… That makes things in several use-cases I recently discussed with @lqst a lot easier.

As I pushed down the Serializable marker to implementations of theoretically custom-implementable things, the change is not API breaking. All the config classes are not implementable by users.

[injectives]

@michael-simons, thanks a lot for taking care of this.

@mattcasters, would you like to give it a spin to see if everything works as you expect?

[mattcasters]

In Apache Hop we switched to google-java-format for reasons like this. Apache Beam is on Spotless / java checker framework. Pick your poison :-)

[michael-simons]

Team checkstyle / Maven enforcer… :D

[mattcasters]

4.4-SNAPSHOT driver works for the existing code. Now I'll try to use Config directly eliminating the wrapper code.

[mattcasters]

I rewrote the Beam Neo4jIO to now allow Config, SessionConfig and TransactionConfig to be passed in since they're now Serializable. This works great! Awesome work guys, thanks a lot!
Do you have an idea if and when this will be available in the next release of neo4j-java-driver?

[injectives]

@mattcasters, unless something urgent comes up, it might get released next week.

[mattcasters]

Fantastic news! Thanks @injectives @michael-simons!