* always under a lock.
     */
    private static final class SupplantableFuture implements Cancellable {
      private final ReentrantLock lock;

      @GuardedBy("lock")
      private Future<@Nullable Void> currentFuture;

      SupplantableFuture(ReentrantLock lock, Future<@Nullable Void> currentFuture) {
        this.lock = lock;
        this.currentFuture = currentFuture;
      }

                return;
            }

            FileChannel channel = null;
            FileLock lock = null;
            try {
                Properties props = new Properties();

                channel = new RandomAccessFile(touchfile, "rw").getChannel();
                lock = channel.lock();

                if (touchfile.canRead()) {

 * test with reference to the same "lock-like object", and then their interactions with that object
 * are choreographed via the various methods on this class.
 *
 * <p>A "lock-like object" is really any object that may be used for concurrency control. If the
 * {@link #callAndAssertBlocks} method is ever called in a test, the lock-like object must have a

  outFinished: Boolean,
  inFinished: Boolean,
  headers: Headers?,
) {
  internal val lock: ReentrantLock = ReentrantLock()
  val condition: Condition = lock.newCondition()

  // Internal state is guarded by [lock]. No long-running or potentially blocking operations are
  // performed while the lock is held.

  /** The bytes consumed and acknowledged by the stream. */
  val readBytes: WindowCounter = WindowCounter(id)

    }
    final ReentrantLock lock = this.lock;
    lock.lock();

    boolean satisfied = false;
    try {
      return satisfied = guard.isSatisfied();
    } finally {
      if (!satisfied) {
        lock.unlock();
      }
    }
  }

  /**
   * Enters this monitor if the guard is satisfied. Blocks at most the given time acquiring the
   * lock, but does not wait for the guard to be satisfied.

   *
   * Lock lockA = factory1.newReentrantLock(MyLockOrder.FIRST);
   * Lock lockB = factory1.newReentrantLock(MyLockOrder.FIRST);
   * Lock lockC = factory2.newReentrantLock(MyLockOrder.FIRST);
   *
   * lockA.lock();
   *
   * lockB.lock();  // will throw an IllegalStateException
   * lockC.lock();  // will throw an IllegalStateException
   *
   * lockA.lock();  // reentrant acquisition is okay

func (ahs *allHealState) setDiskHealingStatus(ep Endpoint, healing bool) {
	ahs.Lock()
	defer ahs.Unlock()

	ahs.healLocalDisks[ep] = healing
}

func (ahs *allHealState) pushHealLocalDisks(healLocalDisks ...Endpoint) {
	ahs.Lock()
	defer ahs.Unlock()

	for _, ep := range healLocalDisks {
		ahs.healLocalDisks[ep] = false
	}
}

	TimeLastRefresh time.Time // Timestamp for last lock refresh.
	Source          string    // Contains line, function and filename requesting the lock.
	Group           bool      // indicates if it was a group lock.
	Owner           string    // Owner represents the UUID of the owner who originally requested the lock.
	Quorum          int       // Quorum represents the quorum required for this lock to be active.

			ok = true
		}
	}
	if ok {
		lock := z.serverPools[0].NewNSLock(minioMetaBucket, rebalMetaName)
		lkCtx, err := lock.GetLock(ctx, globalOperationTimeout)
		if err != nil {
			rebalanceLogIf(ctx, fmt.Errorf("failed to acquire write lock on %s/%s: %w", minioMetaBucket, rebalMetaName, err))
			return err
		}
		defer lock.Unlock(lkCtx)

		ctx = lkCtx.Context()

func (sys *BucketMetadataSys) Remove(buckets ...string) {
	sys.Lock()
	for _, bucket := range buckets {
		delete(sys.metadataMap, bucket)
		globalBucketMonitor.DeleteBucket(bucket)
	}
	sys.Unlock()
}

// RemoveStaleBuckets removes all stale buckets in memory that are not on disk.
func (sys *BucketMetadataSys) RemoveStaleBuckets(diskBuckets set.StringSet) {
	sys.Lock()
	defer sys.Unlock()

	for bucket := range sys.metadataMap {