[refactor][broker] Decouple delayed delivery trackers from dispatcher

[Denovo1998]

Main Issue: #24600

Related PR: #24739

Motivation

PR #24739 currently mixes correctness and threading changes with benchmark and testability refactors, which makes the review difficult to scope. This preparatory PR extracts the delayed delivery tracker context that is needed to construct trackers without a real dispatcher, so the benchmark and test scaffolding can be reviewed separately. The goal is to keep the existing production behavior intact while making the tracker setup reusable from microbench code.

Modifications

• introduce DelayedDeliveryContext plus dispatcher-backed and no-op implementations for delayed delivery trackers
• add context-based and name+cursor-based constructors to the delayed delivery trackers, while keeping the existing dispatcher-based production entry points intact
• update the delayed delivery tracker factories to expose benchmark/test construction helpers without changing the production factory flow
• make MockManagedCursor public for microbench usage and switch the JMH benchmark setup to the new context-based tracker construction
• add MockBucketSnapshotStorage, add the new BucketDelayedDeliveryTrackerBenchmark, and remove the old simple benchmark

Verifying this change

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This change is a trivial rework / code cleanup without any test coverage.

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This change is already covered by existing tests, such as (please describe tests).

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This change added tests and can be verified as follows:

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• Added integration tests for end-to-end deployment with large payloads (10MB)
• Extended integration test for recovery after broker failure

Documentation

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Matching PR in forked repository

PR in forked repository: Denovo1998#24

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[Denovo1998]

@codelipenghui @lhotari @merlimat @coderzc @BewareMyPower @dao-jun
PTAL!

[Copilot]

Pull request overview

Refactors delayed delivery trackers to depend on a lightweight DelayedDeliveryContext abstraction instead of directly depending on the dispatcher, enabling tracker construction in benchmarks/tests without a real dispatcher while keeping the production entry points intact.

Changes:

• Introduce DelayedDeliveryContext plus dispatcher-backed (DispatcherDelayedDeliveryContext) and no-op (NoopDelayedDeliveryContext) implementations.
• Add context-based (and name+cursor-based) constructors/creation helpers for InMemoryDelayedDeliveryTracker and BucketDelayedDeliveryTracker, while preserving existing dispatcher-based construction.
• Update microbench scaffolding: remove the old simple benchmark, add a new BucketDelayedDeliveryTrackerBenchmark, add MockBucketSnapshotStorage, and make MockManagedCursor public for reuse.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
pulsar-broker/src/main/java/org/apache/pulsar/broker/delayed/DelayedDeliveryContext.java	New context interface to decouple trackers from dispatcher.
pulsar-broker/src/main/java/org/apache/pulsar/broker/delayed/DispatcherDelayedDeliveryContext.java	Production context backed by dispatcher operations.
pulsar-broker/src/main/java/org/apache/pulsar/broker/delayed/NoopDelayedDeliveryContext.java	Test/bench-friendly context implementation.
pulsar-broker/src/main/java/org/apache/pulsar/broker/delayed/AbstractDelayedDeliveryTracker.java	Base tracker now uses DelayedDeliveryContext and a context-provided trigger lock.
pulsar-broker/src/main/java/org/apache/pulsar/broker/delayed/InMemoryDelayedDeliveryTracker.java	Adds context/name+cursor constructors; replaces dispatcher references with context.
pulsar-broker/src/main/java/org/apache/pulsar/broker/delayed/InMemoryDelayedDeliveryTrackerFactory.java	Uses dispatcher-backed context internally; adds test/bench helper constructor path.
pulsar-broker/src/main/java/org/apache/pulsar/broker/delayed/BucketDelayedDeliveryTrackerFactory.java	Uses dispatcher-backed context internally; adds test/bench helper constructor path.
pulsar-broker/src/main/java/org/apache/pulsar/broker/delayed/bucket/BucketDelayedDeliveryTracker.java	Adds context/name+cursor constructors; replaces dispatcher references with context.
microbench/src/main/java/org/apache/pulsar/broker/package-info.java	Adds package-level Javadoc (currently targets a higher-level package).
microbench/src/main/java/org/apache/pulsar/broker/delayed/bucket/MockBucketSnapshotStorage.java	Adds a microbench snapshot storage stub.
microbench/src/main/java/org/apache/pulsar/broker/delayed/bucket/BucketDelayedDeliveryTrackerBenchmark.java	New benchmark using context-based tracker construction.
microbench/src/main/java/org/apache/pulsar/broker/delayed/bucket/BucketDelayedDeliveryTrackerSimpleBenchmark.java	Removes old simplified benchmark.
microbench/src/main/java/org/apache/bookkeeper/mledger/impl/MockManagedCursor.java	Makes cursor mock public and factory method public for benchmark reuse.

[Denovo1998]

@nodece
All reviews have been processed.

[Denovo1998]

@nodece All done.

[Copilot]

Pull request overview

Copilot reviewed 11 out of 11 changed files in this pull request and generated 3 comments.

[dao-jun]

LGTM