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Consequently, an unreleased lock in any thread will prevent other threads from acquiring the same lock. Programs must release all actively held locks on exceptional conditions. Intrinsic locks of class objects used for method and block synchronization are automatically released on exceptional conditions (such as abnormal thread termination).
This guideline is an instance of FIO04-J. Release resources when they are no longer needed. However, most Java lock objects are not Closeable, so they cannot be automatically released using Java 7's try-with-resources feature.
Noncompliant Code Example (Checked Exception)
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