125-java-concurrency

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Use when you need to apply Java concurrency best practices — including thread safety fundamentals, ExecutorService thread pool management, concurrent design patterns like Producer-Consumer, asynchronous programming with CompletableFuture, immutability and safe publication, deadlock avoidance, virtual threads, structured concurrency, scoped values, backpressure, cancellation discipline, and observability for concurrent systems. This should trigger for requests such as Review Java code for concurrency; Review Java code for thread safety; Fix race conditions in Java concurrency code; Choose ExecutorService or virtual threads in Java; Improve synchronization and shared mutable state handling; Apply structured concurrency for related Java subtasks. Part of Plinth Toolkit

AI & Automation 439 stars 92 forks Updated today Apache-2.0

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Skill Content

# Java rules for Concurrency objects Identify and apply Java concurrency best practices to improve thread safety, scalability, and maintainability by using modern `java.util.concurrent` utilities and virtual threads. **What is covered in this Skill?** - Thread safety fundamentals: `ConcurrentHashMap`, `AtomicInteger`, `ReentrantLock`, `ReadWriteLock`, Java Memory Model - `ExecutorService` thread pool configuration: sizing, keep-alive, bounded queues, rejection policies, graceful shutdown - Producer-Consumer and Publish-Subscribe patterns with `BlockingQueue` - `CompletableFuture` for non-blocking async composition (`thenApply`/`thenCompose`/`exceptionally`/`orTimeout`) - Immutability and safe publication (`volatile`, static initializers) - Lock contention and false-sharing performance optimization - Virtual threads (`Executors.newVirtualThreadPerTaskExecutor()`) for I/O-bound scalability - Structured Concurrency (`StructuredTaskScope`) for related subtasks in Java 27 preview - `ScopedValue` over `ThreadLocal` for immutable cross-task data - Cooperative cancellation and `InterruptedException` discipline - Backpressure with bounded queues and `CallerRunsPolicy` - Deadlock avoidance via global lock ordering and `tryLock` with timeouts - ForkJoin/parallel-stream discipline for CPU-bound work - Virtual-thread pinning detection (JFR `VirtualThreadPinned`) - Thread naming and `UncaughtExceptionHandler` observability - Fit-for-purpose primitives: `LongAdder`, `CopyOnWriteArrayList...

Details

Author
jabrena
Repository
jabrena/plinth
Created
1 years ago
Last Updated
today
Language
Java
License
Apache-2.0

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Model Context Protocol · AI

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plinth

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