Lazy initialization of static fields should be synchronized

[kirill-vlasov]

This pull request is focused on resolving occurrences of Sonar rule squid:S2444 - Lazy initialization of static fields should be synchronized
You can find more information about the issue here:
https://dev.eclipse.org/sonar/coding_rules#q=squid:S2444
Please let me know if you have any questions.
Kirill Vlasov

[dreab8]

Hi @kirill-vlasov , can you open a Jira for this issue.

Thanks a lot

[richardfontana]

@vladmihalcea this can be merged without needing the CLA. Thanks!

[vladmihalcea]

@kirill-vlasov The SessionFactory bootstrap is meant to be executed from within a single thread. After it starts, the SessionFactory can be used by multiple Threads, so I'm not sure what this change will buy us. Adding synchronized when unnecessary can incur some small overhead that might not bring us any benefit. For this reason, I think we should close this PR.

[Sanne]

Good catch, something is fishy here! Yet synchronizing is not the best solution, as it would introduce a contention point while it's not necessary.
The memberMethod should be made final and initialized statically.

Also, would be nice to have fields at the beginning of the class.

[Sanne]

@richardfontana thanks! It's great to see you around, even more helping so directly.

[vladmihalcea]

I created HHH-10715 for analyzing static field usage.

[Sanne]

I was just checking for similar patterns, and I'm glad to say that most issues had already been resolved. I just fixed the remaining cases.