CAMEL-23495: Replace Thread.sleep() with Awaitility in camel-core and camel-management tests

[gnodet]

CAMEL-23495

Replace Thread.sleep() synchronization calls with Awaitility in 15 test files across camel-core and camel-management to reduce flakiness under CI load.

Changes by category

Suspend/resume tests (4 files)

• RouteSedaSuspendResumeTest, DefaultCamelContextSuspendResumeRouteTest, TwoRouteSuspendResumeTest, SedaConsumerSuspendResumeTest
• Replaced Thread.sleep(1000L) + existing await() with a single await().pollDelay(1s).atMost(5s) to give SEDA consumer thread time to idle after route suspension

Management tests (2 files)

• ManagedInflightStatisticsTest — replaced Thread.sleep(250) and Thread.sleep(200) with await().until() checking JMX inflight exchange count
• DefaultExecutorServiceManagerTest — replaced Thread.sleep(3000) with a started CountDownLatch + await() to detect when the pool task begins

Async/scheduler tests (2 files)

• SchedulerMulticastParallelGreedyTest — replaced Thread.sleep(50) with MockEndpoint.setAssertPeriod(200) to verify no extra messages arrive
• ThreadsRejectedExecutionWithDeadLetterTest — replaced Thread.sleep(100) with await().until() checking the rejected message arrived at dead letter

Aggregation tests (3 files)

• AggregateGroupedExchangeBatchSizeTest — replaced Thread.sleep(1000) with await() for the second batch via completion timeout
• AggregateDiscardOnTimeoutTest — replaced Thread.sleep(250) with MockEndpoint.setAssertPeriod(500)
• AggregateClosedCorrelationKeyTest — replaced Thread.sleep(200) with await().until() checking all aggregated results arrived

Redelivery/shutdown tests (3 files)

• NotAllowRedeliveryWhileStoppingTest, NotAllowRedeliveryWhileStoppingDeadLetterChannelTest — replaced Thread.sleep(500) with await() checking inflight repository
• RedeliveryDeadLetterErrorHandlerNoRedeliveryOnShutdownTest — replaced Thread.sleep(500) with await().until(() -> counter.get() >= 20)

Resequencer test (1 file)

• ResequenceStreamRejectOldExchangesTest — replaced Thread.sleep(100) with await().until() checking first message delivered before sending the rest

Out of scope

The following Thread.sleep() uses were intentionally left unchanged:

• Sleeps inside Processor.process() or Runnable.run() simulating slow I/O
• Timing-specific tests (completion intervals, rate calculations, timeout ordering)
• Pacing sleeps between message sends where the delay is the test's intent

Claude Code on behalf of Guillaume Nodet

[apupier]

there is no await replacement then this thread;sleep. This could only be worse than it currently is

[gnodet]

What about the pollDelay(1, TimeUnit.SECONDS) ?

[gnodet]

Fixed in ef24703 — now split into two await() calls: first checks queues are empty, then uses pollDelay(1s) to give the consumer thread time to idle after the queues empty. The second await also asserts the consumer status is Suspended.

Claude Code on behalf of Guillaume Nodet

[apupier]

there isn't a wait condition anymore ensuring that the message is suspended

[gnodet]

What about the pollDelay(1, TimeUnit.SECONDS) ?

[gnodet]

Fixed in ef24703 — now split into two await() calls: first checks context.isSuspended(), then uses pollDelay(1s) to give the seda consumer thread time to complete its poll cycle before sending the test message.

Claude Code on behalf of Guillaume Nodet

[apupier]

there is no await replacement then this thread;sleep. This could only be worse than it currently is

[gnodet]

What about the pollDelay(1, TimeUnit.SECONDS) ?

[apupier]

The poll Delay is before checking for for the suspension and the big comment is explaining that we need to wait after this point due to async behavior

[gnodet]

You're right, the pollDelay was before the condition check, but the original Thread.sleep was after the queue-empty await. Fixed in ef24703 — now split into two steps:

1. await().until(queue.isEmpty()) — checks the condition first
2. await().pollDelay(1s).untilAsserted(...) — then gives the consumer thread time to idle

This preserves the original semantics: wait for the queue to empty, then wait for the consumer to stop its poll loop.

Claude Code on behalf of Guillaume Nodet

[ghost]

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[gnodet]

Thanks for the review! You're right — the pollDelay was placed before the condition check, but the original Thread.sleep was after the queue-empty check. Fixed in ef24703: now using two-step await:

1. First await().until(queue.isEmpty()) — checks the condition
2. Second await().pollDelay(1s).untilAsserted(...) — gives the consumer thread time to idle after the queue empties

Claude Code on behalf of Guillaume Nodet

[ghost]

🧪 CI tested the following changed modules:

• core/camel-core
• core/camel-management

ℹ️ Dependent modules were not tested because the total number of affected modules exceeded the threshold (50). Use the test-dependents label to force testing all dependents.

⚠️ Some tests are disabled on GitHub Actions (@DisabledIfSystemProperty(named = "ci.env.name")) and require manual verification:

• core/camel-core: 2 test(s) disabled on GitHub Actions

Build reactor — dependencies compiled but only changed modules were tested (2 modules)

• Camel :: Core
• Camel :: Management

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[gnodet]

Commits cherry-picked into #23178 which consolidates all flaky test fixes.