Harden priority queue scheduler
Hard Java arena: PriorityQueue comparators and stable ordering
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Missing prerequisites: java-easy-priority-queue
A batch worker must pick the urgent task, then the oldest task, then the lowest ID. 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 PriorityQueue comparators and stable ordering in a Java backend interview lab while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates PriorityQueue comparators and stable ordering
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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