[SOLR-14239] Fix the behavior of CaffeineCache.computeIfAbsent on branch_8x

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 8.4.1
• Fix Version/s: 8.5
• Assignee: Andrzej Bialecki
• Reporter: Andrzej Bialecki
• Created: 04/Feb/20 12:53
• Updated: 27/May/20 18:04
• Resolved: 04/Feb/20 16:04

Description

Spin-off from SOLR-13817, spotted by Andy Webb.

The back-port of CaffeineCache to branch_8x is missing a conditional statement in computeIfAbsent which breaks the contract of this method, i.e. if the loading function returns null the cache mapping should remain unchanged and a null value should be returned.

Note: this only affects branch_8x, master already has this conditional.

This issue also modifies comments in the default solrconfig.xml to indicate that the old cache implementations existing in branch_8x are deprecated in favor of CaffeineCache.

Issue Links

• is related to: SOLR-13817 Deprecate and remove legacy SolrCache implementations