[SOLR-16713] Replace Guava usages with pure Java

• Type: Task
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: main (10.0), 9.3
• Assignee: Kevin Risden
• Reporter: Kevin Risden
• Created: 21/Mar/23 13:33
• Updated: 21/Jul/23 20:40
• Resolved: 02/Apr/23 13:45

Description

Guava is used in a variety of places that can be simplified especially with Java streams.

• Preconditions -> Objects
• Strings.isNullOrEmpty -> Simple helper method on StrUtils
• Maps/ImmutableMap -> Java Map
• Lists/ImmutableList -> Java List
• Sets/ImmutableSet/ImmutableSortedSet -> Java Set
• Collections2/Iterables/Iterators/ObjectArrays -> Java Stream
• Guava cache -> Caffeine cache

This ends up removing the Guava dependency from 4 build.gradle files:

• modules/analytics
• modules/sql
• modules/gcs-repository - test
• solrj - test

---

Second pass cleans up

• com.google.common.base.Throwables
• com.google.common.collect.ImmutableMap
• com.google.common.collect.**
• com.google.common.io.** (and consequently org.apache.commons.io.IOUtils#toString(java.io.Reader) since its the same usage)

This ends up removing Guava dependency from

• test-framework
• solrj-zookeeper - test

Issue Links

• links to: GitHub Pull Request #1466
• links to: GitHub Pull Request #1501