ArC - replace Collections.unmodifiableSet() with JDK immutable set

[mkouba]

This is only the first part of optimizations.

[quarkus-bot]

This workflow status is outdated as a new workflow run has been triggered.

Failing Jobs - Building 419a854

Status	Name	Step	Failures	Logs	Raw logs
✖	Initial JDK 11 Build	Build	Failures	Logs	Raw logs

Failures

⚙️ Initial JDK 11 Build #

- Failing: independent-projects/arc/processor 
! Skipped: core/test-extension/deployment devtools/bom-descriptor-json devtools/cli and 404 more

📦 independent-projects/arc/processor

✖ Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1-jboss-2:compile (default-compile) on project arc-processor: Compilation failure /home/runner/work/quarkus/quarkus/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/MethodDescriptors.java:[106,95] cannot find symbol symbol: class Objects location: class io.quarkus.arc.processor.MethodDescriptors

[Sanne]

Looks nice! I haven't looked much into the new types; do they take less space?

[Ladicek]

The Set.of() return type is a direct implementation of an immutable set, so it should be more efficient by definition, both from time and space perspective. Specifically, the old code used Collections.unmodifiableSet() over a HashSet. A HashSet holds a HashMap. The HashMap holds an array, where each element is a linked list or a binary tree (open hashing). On the other hand, Set.of(more than 2 elements) returns an instance that directly holds an array of values (closed hashing). The only thing that may be worse is that the array size in the Set.of() implementation is 2 * the number of elements -- but that would only be worse when the set contained a big number of values, which should almost never be the case here.

[mkouba]

Thanks Ladislav for an exhaustive description ;-).

but that would only be worse when the set contained a big number of values, which should almost never be the case here

Those sets will have a maximum of dozens of elements, but mostly less than ten elements.

[quarkus-bot]

Failing Jobs - Building c802ed3

Status	Name	Step	Failures	Logs	Raw logs
✖	Gradle Tests - JDK 11 Windows	Build	Failures	Logs	Raw logs

Full information is available in the Build summary check run.

Failures

⚙️ Gradle Tests - JDK 11 Windows #

- Failing: integration-tests/gradle 

📦 integration-tests/gradle

✖ io.quarkus.gradle.devmode.BasicKotlinApplicationModuleDevModeTest.main line 18 - More details - Source on GitHub

org.awaitility.core.ConditionTimeoutException: Condition with lambda expression in io.quarkus.test.devmode.util.DevModeTestUtils that uses java.util.function.Supplier, java.util.function.Supplierjava.util.concurrent.atomic.AtomicReference, java.util.concurrent.atomic.AtomicReferencejava.lang.String, java.lang.Stringboolean was not fulfilled within 1 minutes.
	at org.awaitility.core.ConditionAwaiter.await(ConditionAwaiter.java:166)
	at org.awaitility.core.CallableCondition.await(CallableCondition.java:78)