Implement Thread-Specific Storage Pattern

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Description

Thread-Specific Storage is a concurrency design pattern where each thread retains its own instance of a shared object, typically achieved using ThreadLocal<T> in Java. By isolating data to each thread, you avoid synchronization overhead and minimize concurrency issues. Common use cases include storing thread-specific contexts, caching stateful objects like DateFormat, or managing per-thread counters without risking data corruption or race conditions.

Key Elements

• Isolation of State: Each thread has its own copy of the data, reducing shared mutable state.
• ThreadLocal Utility: Java’s ThreadLocal<T> class provides a straightforward way to store data private to each thread.
• Initialization & Cleanup: Properly initializing and cleaning up thread-local data is crucial to prevent memory leaks.
• Practical Use Cases: Storing per-thread data such as locale-specific formatters, current transaction context, or local caches.

References

1. Pattern-Oriented Software Architecture, Volume 2: Patterns for Concurrent and Networked Objects
2. Java Design Patterns - Contribution Guidelines

Acceptance Criteria

• A new module or package named thread-specific-storage (or similar) is added.
• Demonstrates a clear use case of storing and retrieving thread-local data (e.g., per-thread state).
• Includes a readme (or .md file) explaining how the pattern works, with code examples or diagrams.
• Adheres to the repository’s coding style and naming conventions.
• Includes unit tests verifying behavior in a multi-threaded scenario.
• Passes all CI checks and meets the project’s contribution guidelines.