*/
  @CanIgnoreReturnValue
  public static long copy(Readable from, Appendable to) throws IOException {
    // The most common case is that from is a Reader (like InputStreamReader or StringReader) so
    // take advantage of that.
    if (from instanceof Reader) {
      // optimize for common output types which are optimized to deal with char[]
      if (to instanceof StringBuilder) {

     * all other executions until finished.
     * We also lock on a given project to forbid a forked lifecycle to be executed concurrently with the project.
     * TODO: ideally, the builder should take care of the ordering in a smarter way
     * TODO: and concurrency issues fixed with MNG-7157
     */
    protected class ProjectLock implements NoExceptionCloseable {
        final Lock acquiredAggregatorLock;

  }

  static final class Crc32cHasher extends AbstractStreamingHasher {

    /*
     * The striding algorithm works roughly as follows: it is universally the case that
     * CRC(x ^ y) == CRC(x) ^ CRC(y).  The approach we take is to break the message as follows,
     * with each letter representing a 4-byte word: ABCDABCDABCDABCD... and to calculate
     * CRC(A000A000A000...), CRC(0B000B000B...), CRC(00C000C000C...), CRC(000D000D000D...)

        }

        currentVersion = allVersions.last();

        groupByMajor = allVersions.stream()
            // We only care about the last 2 majors when it comes to BWC.
            // It might take us time to remove the older ones from versionLines, so we allow them to exist.
            .filter(version -> version.getMajor() > currentVersion.getMajor() - 2)

    if (reference == null) {
      throw new VerifyException(lenientFormat(errorMessageTemplate, errorMessageArgs));
    }
    return reference;
  }

  // TODO(kevinb): consider <T> T verifySingleton(Iterable<T>) to take over for
  // Iterables.getOnlyElement()

  private Verify() {}

     */
    public void setShareAccess(final int shareAccess) {
        this.shareAccess = shareAccess;
    }

    /**
     * Set the create disposition specifying what action to take if file exists or doesn't exist
     * @param createDisposition the createDisposition to set
     */
    public void setCreateDisposition(final int createDisposition) {
        this.createDisposition = createDisposition;

        authenticator.setMaxGroupDepth(3);

        List<String> groupList = new ArrayList<>();
        List<String> roleList = new ArrayList<>();

        // Test the overload that doesn't take depth parameter
        // It should call the depth-tracking version with depth 0
        try {
            authenticator.processParentGroup(null, groupList, roleList, "test-id");
        } catch (Exception e) {

    ImmutableSet.Builder<ImmutableList<Class<?>>> allOverloads = ImmutableSet.builder();
    // The first two are for the overloads that don't take formatting args, e.g.
    // checkArgument(boolean) and checkArgument(boolean, Object)
    allOverloads.add(ImmutableList.<Class<?>>of(predicateType));
    allOverloads.add(ImmutableList.<Class<?>>of(predicateType, Object.class));

    ImmutableSet.Builder<ImmutableList<Class<?>>> allOverloads = ImmutableSet.builder();
    // The first two are for the overloads that don't take formatting args, e.g.
    // checkArgument(boolean) and checkArgument(boolean, Object)
    allOverloads.add(ImmutableList.<Class<?>>of(predicateType));
    allOverloads.add(ImmutableList.<Class<?>>of(predicateType, Object.class));

For active-active replication, automatic failover occurs on `GET/HEAD` operations if object or object version requested qualifies for replication and is missing on one site, but present on the other. This allows the applications to take full advantage of two-way replication even before the two sites get fully synced.