*
 * <ul>
 *   <li>for an unnested {@code lock()} and {@code unlock()}, a cycle detecting lock takes 38ns as
 *       opposed to the 24ns taken by a plain lock.
 *   <li>for nested locking, the cost increases with the depth of the nesting:
 *       <ul>
 *         <li>2 levels: average of 64ns per lock()/unlock()
 *         <li>3 levels: average of 77ns per lock()/unlock()
 *         <li>4 levels: average of 99ns per lock()/unlock()

      } finally {
        unlock();
        postWriteCleanup();
      }
    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          drainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

      - name: 'Set up JDKs'
        uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # v5.2.0
        with:
          # For discussion, see the first setup-java block.
          # The publish-snapshot workflow doesn't run tests, so we don't have to care which version Maven would select for that step.
          java-version: 25
          distribution: 'temurin'
          cache: 'maven'

      } finally {
        unlock();
        postWriteCleanup();
      }
    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          drainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          maybeDrainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    @GuardedBy("this")

    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          maybeDrainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    @GuardedBy("this")

 * "value" of a successful step or the "result" (value or exception) of any step.
 *
 * <ol>
 *   <li>A pipeline starts at its leaf step (or steps), which is created from either a callable
 *       block or a {@link ListenableFuture}.
 *   <li>Each other step is derived from one or more input steps. At each step, zero or more objects
 *       can be captured for later closing.

   * BiMap<Long, String> map = Maps.synchronizedBiMap(HashBiMap.create());
   * ...
   * Set<Long> set = map.keySet(); // Needn't be in synchronized block
   * ...
   * synchronized (map) { // Synchronizing on map, not set!
   *   Iterator<Long> it = set.iterator(); // Must be in synchronized block
   *   while (it.hasNext()) {
   *     foo(it.next());
   *   }
   * }
   * }
   *

   * BiMap<Long, String> map = Maps.synchronizedBiMap(HashBiMap.create());
   * ...
   * Set<Long> set = map.keySet(); // Needn't be in synchronized block
   * ...
   * synchronized (map) { // Synchronizing on map, not set!
   *   Iterator<Long> it = set.iterator(); // Must be in synchronized block
   *   while (it.hasNext()) {
   *     foo(it.next());
   *   }
   * }
   * }
   *

      }
    }

    return spec;
  }

  /** Returns a CacheBuilderSpec that will prevent caching. */
  public static CacheBuilderSpec disableCaching() {
    // Maximum size of zero is one way to block caching
    return CacheBuilderSpec.parse("maximumSize=0");
  }

  /** Returns a CacheBuilder configured according to this instance's specification. */
  CacheBuilder<Object, Object> toCacheBuilder() {