* 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;
      }

			buf.Reset()
			bytebufferpool.Put(buf)
		}()

		block := newMetacacheWriter(buf, 1<<20)
		defer block.Close()
		finishBlock := func() {
			if err := block.Close(); err != nil {
				w.streamErr = err
				return
			}
			current.data = buf.Bytes()
			w.streamErr = nextBlock(&current)
			// Prepare for next
			current.n++
			buf.Reset()
			block.Reset(buf)
			current.First = ""
		}

     * error-prone code like:
     *
     * Striped<Lock> stripedLock = Striped.lazyWeakXXX(...)'
     * Iterable<Lock> locks = stripedLock.bulkGet(keys);
     * for (Lock lock : locks) {
     *   lock.lock();
     * }
     * operation();
     * for (Lock lock : locks) {
     *   lock.unlock();
     * }
     *

     * returned.
     *
     * If upstream would be selected but another thread is already reading upstream this will
     * block until that read completes. It is possible to time out while waiting for that.
     */
    @Throws(IOException::class)
    override fun read(
      sink: Buffer,
      byteCount: Long,
    ): Long {
      check(fileOperator != null)

func (t *transitionState) addLastDayStats(tier string, ts tierStats) {
	t.lastDayMu.Lock()
	defer t.lastDayMu.Unlock()

	if _, ok := t.lastDayStats[tier]; !ok {
		t.lastDayStats[tier] = &lastDayTierStats{}
	}
	t.lastDayStats[tier].addStats(ts)
}

func (t *transitionState) getDailyAllTierStats() DailyAllTierStats {
	t.lastDayMu.RLock()
	defer t.lastDayMu.RUnlock()

//     slots are used for object offloading or writing)
//
//   - <KbBlockSize>
//     Veeam Block Size for backup and restore processing before compression is applied. The higher the block size, the more
//     backup space is needed for incremental backups. Larger block sizes also mean less performance for random read restore

import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;

/** Forwarding wrapper around a {@code Lock}. */
@J2ktIncompatible
@GwtIncompatible
abstract class ForwardingLock implements Lock {
  abstract Lock delegate();

  @Override
  public void lock() {
    delegate().lock();
  }

  @Override
  public void lockInterruptibly() throws InterruptedException {

        "fe012443-6ba9-4ef2-bb94-b729d2060c78/test123/testw3c.pdf/xl.meta": {"Versions":[{"Type":1,"V2Obj":{"ID":"aGEA/ZUOR4ueRIZs...

        lock.readLock().lock();
        try {
            lastAccessTime = System.currentTimeMillis();
            return children.get(name);
        } finally {
            lock.readLock().unlock();
        }
    }
    
    public boolean hasChild(String name) {
        lock.readLock().lock();
        try {
            lastAccessTime = System.currentTimeMillis();
            return children.containsKey(name);

import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;

/** Forwarding wrapper around a {@code Lock}. */
@J2ktIncompatible
@GwtIncompatible
abstract class ForwardingLock implements Lock {
  abstract Lock delegate();

  @Override
  public void lock() {
    delegate().lock();
  }

  @Override
  public void lockInterruptibly() throws InterruptedException {