defer cancel()

	err := target.checkAndInitClient(ctx)
	if err != nil {
		return err
	}

	eventData, eErr := target.store.Get(key)
	if eErr != nil {
		// The last event key in a successful batch will be sent in the channel atmost once by the replayEvents()
		// Such events will not exist and wouldve been already been sent successfully.
		if os.IsNotExist(eErr) {
			return nil
		}

              return true;
            }
          }
        }
        sum += segment.modCount;
      }
      if (sum == last) {
        break;
      }
      last = sum;
    }
    return false;
  }

  @CheckForNull
  @CanIgnoreReturnValue
  @Override
  public V put(K key, V value) {
    checkNotNull(key);

  final Weigher<K, V> weigher;

  /** How long after the last access to an entry the map will retain that entry. */
  final long expireAfterAccessNanos;

  /** How long after the last write to an entry the map will retain that entry. */
  final long expireAfterWriteNanos;

  /** How long after the last write an entry becomes a candidate for refresh. */
  final long refreshNanos;

	}
	for k, v := range d.Cache {
		clone.Cache[k] = v.clone()
	}
	return clone
}

// merge root of other into d.
// children of root will be flattened before being merged.
// Last update time will be set to the last updated.
func (d *dataUsageCache) merge(other dataUsageCache) {
	existingRoot := d.root()
	otherRoot := other.root()
	if existingRoot == nil && otherRoot == nil {
		return
	}

Docker and similar tools also use an **internal cache** when building the image, if a file hasn't changed since the last time building the container image, then it will **reuse the same layer** created the last time, instead of copying the file again and creating a new layer from scratch.

   */
  @Beta
  @Deprecated
  @J2ObjCIncompatible
  public static File createTempDir() {
    return TempFileCreator.INSTANCE.createTempDir();
  }

  /**
   * Creates an empty file or updates the last updated timestamp on the same as the unix command of
   * the same name.
   *
   * @param file the file to create or update
   * @throws IOException if an I/O error occurs
   */

## Overview

Replication relies on immutability provided by versioning to sync objects between the configured source and replication target. Replication results in the object data, metadata, last modification time and version ID all being identical between the source and target. Thus version ordering is automatically guaranteed on the source and target clusters.

### Replication of object version and metadata

    testRotate(new byte[] {0, 1, 2, 3, 4, 5, 6}, 1, 0, 3, new byte[] {2, 0, 1, 3, 4, 5, 6});
    testRotate(new byte[] {0, 1, 2, 3, 4, 5, 6}, 2, 0, 3, new byte[] {1, 2, 0, 3, 4, 5, 6});

    // Rotate the last four elements
    testRotate(new byte[] {0, 1, 2, 3, 4, 5, 6}, -6, 3, 7, new byte[] {0, 1, 2, 5, 6, 3, 4});
    testRotate(new byte[] {0, 1, 2, 3, 4, 5, 6}, -5, 3, 7, new byte[] {0, 1, 2, 4, 5, 6, 3});

                            " but readBytesWireFormat returned " + n );
                }
            }
            // Don't think we can rely on n being correct here. Must use byteCount.
            // Last paragraph of section 3.13.3 eludes to this.

            bufferIndex += byteCount;
        }

        length = bufferIndex - start;
        return length;
    }

	case closed:
		// client closed, this is usually a manual process
		// so return a local error as client is closed
		return nil, &NetworkError{Err: ErrClientClosed}
	case offline:
		// client offline, return last error captured.
		return nil, &NetworkError{Err: c.LastError()}
	}

	// client is still connected, attempt the request.

	// Shallow copy. We don't modify the *UserInfo, if set.
	// All other fields are copied.