Java 17 features in Elasticsearch code base

[astefan]

This is a meta issue for tracking Java 17 features implementation in Elasticsearch. The work is composed of the following tasks:

• Pattern matching for instanceof. Tasks are divided between folders under https://github.com/elastic/elasticsearch. The split also takes into consideration that some of the above mentioned folders do not contain any instanceof occurrences that can be transitioned to pattern matching.
  • x-pack/plugin/analytics through x-pack/plugin/enrich @astefan #x-pack batch 1 instanceof pattern matching replacement #81812
  • x-pack/plugin/eql through x-pack/plugin/searchable-snapshots @astefan x-pack batch 2 instanceof pattern matching replacement #81936
  • x-pack/plugin/security through x-pack/plugin/wildcard @astefan x-pack batch 3 instanceof pattern matching replacement #81996
  • build-conventions through modules
    • ingest modules (Refactor ingest to use instanceof pattern matching where possible #81656)
    • build-conventions through modules folders except ingest modules @astefan Java 17 instanceof pattern matching for modules #82341
  • plugins through qa, server/internalClusterTest @gmarouli refactor instanceof in plugins through qa and server/internalServerTest #82161
  • server @idegtiarenko server instanceof pattern matching replacement #82074
  • test, x-pack/qa @astefan Java 17 instanceof pattern matching for test and x-pack/qa #82683
  • Final check for leftovers @astefan Java 17 instanceof pattern matching leftovers #82768
  • equals @arteam via Use pattern variables for instanceof for type casting in equals #84315
• Text blocks @arteam Use Java 15 text blocks for JSON and multiline strings #80751
• Improved switch expressions @arteam via Use Java 14 switch expressions #82178
• Pattern matching for switch
• Sealed classes
• Records
  • Part 1 @arteam Migrate to Java 16 Records (part 1) #82338
  • Part 2 @arteam Migrate to Java 16 records (part 2) #82914

[elasticmachine]

Pinging @elastic/es-core-infra (Team:Core/Infra)