fix(hotreload): Unset INSTANCE of executor on shutdown

[chriswk]

fixes #315

[Copilot]

Pull Request Overview

This PR fixes issue #315 by ensuring the singleton INSTANCE of the scheduled executor is properly reset to null during shutdown, preventing stale references during hot reload scenarios.

Key changes:

• Modified the setInterval method to return void instead of ScheduledFuture across all implementations
• Added proper INSTANCE cleanup in shutdown methods to support hot reload scenarios
• Enhanced logging for better debugging of executor lifecycle events

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
UnleashScheduledExecutor.java	Updated interface to change setInterval return type and added shutdownNow method
UnleashScheduledExecutorImpl.java	Implemented INSTANCE cleanup in shutdown methods and added logging
SynchronousTestExecutor.java	Updated test implementation to match new interface signature

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[Copilot]

Setting INSTANCE to null in shutdown methods creates a race condition. If another thread calls getInstance() while shutdown is executing, it could create a new instance of an executor that's being shut down. Consider using proper synchronization or marking the instance as shutting down before nullifying it.

Suggested change

	public void shutdown() {
	this.scheduledThreadPoolExecutor.shutdown();
	INSTANCE = null;
	LOG.info("Shutdown - Scheduled Executor");
	}
	@Override
	public void shutdownNow() {
	public synchronized void shutdown() {
	this.scheduledThreadPoolExecutor.shutdown();
	INSTANCE = null;
	LOG.info("Shutdown - Scheduled Executor");
	}
	@Override
	public synchronized void shutdownNow() {

[Copilot]

Setting INSTANCE to null in shutdown methods creates a race condition. If another thread calls getInstance() while shutdown is executing, it could create a new instance of an executor that's being shut down. Consider using proper synchronization or marking the instance as shutting down before nullifying it.

Suggested change

	public void shutdown() {
	this.scheduledThreadPoolExecutor.shutdown();
	INSTANCE = null;
	LOG.info("Shutdown - Scheduled Executor");
	}
	@Override
	public void shutdownNow() {
	public synchronized void shutdown() {
	this.scheduledThreadPoolExecutor.shutdown();
	INSTANCE = null;
	LOG.info("Shutdown - Scheduled Executor");
	}
	@Override
	public synchronized void shutdownNow() {

[gastonfournier]

I think this makes sense

[coveralls]

Pull Request Test Coverage Report for Build 17575487826

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 6 of 6 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.2%) to 79.472%

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Totals
Change from base Build 16902971413:	0.2%
Covered Lines:	1229
Relevant Lines:	1510

---

💛 - Coveralls

[gastonfournier]

I think this can work. I've added a small suggestion inline with Copilot suggestion: #325

[gastonfournier]

Should this be debug?

[chriswk]

It shouldn't be here at all. I'll remove it before merging

[gastonfournier]

Should this be debug? or be removed altogether

[chriswk]

Same, shouldn't be here. Added to verify behaviour during testing in example.