MLE-29324, MLE-29325: Fix silent NPE in getSslContext() and IndexOutOfBoundsException in ThreadManager Thread Scaling

[tposham]

Backport from develop

Fix silent NPE in ContentReader.SslOptions.getSslContext()

When SSLContext.getInstance("TLSv1.3") throws NoSuchAlgorithmException, the catch block swallows the exception and execution continues with sslContext = null, causing an NPE on sslContext.init().

Fix:

• Removed try-catch blocks that swallowed exceptions
• Added throws NoSuchAlgorithmException, KeyManagementException to align with the SslConfigOptions interface contract
• Exceptions now propagate to the caller which already handles them properly

Fix IndexOutOfBoundsException in ThreadManager thread scaling

LocalJobRunner.java:

• Moved runThreadPoller() from before task submission to after, ensuring threads exist before the poller attempts to scale them

ThreadManager.java:

• Added bounds checking with activeIdx in scaleOut() and scaleIn() to prevent IndexOutOfBoundsException when scaling beyond available thread pool size

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Tests

• Ran unit tests → All passed
• Ran 06mlcp test suite → No regression failures were found

[Copilot]

Pull request overview

This PR backports fixes that prevent two runtime failures in mlcp: a silent null SSLContext leading to an NPE during SSL initialization, and an IndexOutOfBoundsException during auto-scaling thread allocation in ThreadManager.

Changes:

• Propagate NoSuchAlgorithmException/KeyManagementException from SslOptions.getSslContext() instead of swallowing them and proceeding with a null SSLContext.
• Prevent IndexOutOfBoundsException in thread scaling/idle-thread assignment by decoupling iteration over taskList from indexing into randomIndexes.
• Start the thread poller after task submission in LocalJobRunner to avoid races between active-task snapshotting and scaling iteration.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/main/java/com/marklogic/mapreduce/examples/ContentReader.java	Stops swallowing SSL initialization exceptions to prevent a follow-on NPE.
src/main/java/com/marklogic/contentpump/ThreadManager.java	Adds bounds-safe indexing when distributing threads during scale-in/out and idle reassignment.
src/main/java/com/marklogic/contentpump/LocalJobRunner.java	Defers starting the thread poller until after tasks are submitted to reduce scaling races.

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[abika5]

Hi @tposham - This change impacts the thread manager and will need performance validations as well. Please let Andrea know that this change has been added, and we should monitor how this impacts the performance of mlcp.

And please use branching in the repository to make changes rather than forks.

[yunzvanessa]

The code change looks good. Thanks. Please make sure to stop using forks to generate PRs.