Re-opened: Generic lowerBound() and upperBound() Utility Methods for Collections and Arrays with 100% Test Coverage

[adi1103sh]

This introduces fully tested, generic utility methods:
lowerBound() and upperBound() — for:

Collection

T[] (wrapper/object arrays)

Primitive arrays: int[], long[], char[], short[], float[], double[]

These methods are frequently used in DSA problems, competitive programming, and time-constrained interviews. While C++ developers have access to std::lower_bound and std::upper_bound via STL, Java developers are often forced to re-implement these manually each time — leading to redundancy, reduced productivity, and more boilerplate during contests.

🔥 Key Highlights:

🚀 Optimized binary search logic internally for performance-critical use cases

📦 Supports both object-based and primitive-based containers

📚 Added JavaDocs to all test methods for clarity

💡 Why This Matters:

Reduces friction for Java developers during competitive programming, hackathons, and technical interviews

Brings parity with C++ STL, avoiding time wasted on re-implementing well-known patterns

Enhances reusability in both DSA libraries and production codebases that rely on sorted datasets

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Error

 ⚠️ OCA signatory status must be verified

Reviewing

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[bridgekeeper]

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[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

@adi1103sh The following label will be automatically applied to this pull request:

• core-libs

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[adi1103sh]

/signed

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[bridgekeeper]

@adi1103sh This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply issue a /touch or /keepalive command to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[adi1103sh]

/keepalive

[openjdk]

@adi1103sh The pull request is being re-evaluated and the inactivity timeout has been reset.