Harden concurrent counter repair
Hard Java arena: AtomicInteger, synchronization, and race-condition reasoning
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Missing prerequisites: java-easy-concurrent-counter
Metrics counters are missing increments during high-concurrency tests. You are working inside a Java backend interview lab, and the arena only clears when the result is safe, deterministic, and explainable.
Learn to apply AtomicInteger, synchronization, and race-condition reasoning in a Java backend interview lab while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates AtomicInteger, synchronization, and race-condition reasoning
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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