@GwtIncompatible // used only from other GwtIncompatible code
  private static final class BitSetMatcher extends NamedFastMatcher {

    private final BitSet table;

    private BitSetMatcher(BitSet table, String description) {
      super(description);
      if (table.length() + Long.SIZE < table.size()) {
        table = (BitSet) table.clone();
        // If only we could actually call BitSet.trimToSize() ourselves...

	ErrInvalidDataSource: {
		Code:           "InvalidDataSource",
		Description:    "Invalid data source type. Only CSV and JSON are supported at this time.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrInvalidExpressionType: {
		Code:           "InvalidExpressionType",
		Description:    "The ExpressionType is invalid. Only SQL expressions are supported at this time.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrBusy: {

   * <p><i>Performance notes:</i> while the power set of a set with size {@code n} is of size {@code
   * 2^n}, its memory usage is only {@code O(n)}. When the power set is constructed, the input set
   * is merely copied. Only as the power set is iterated are the individual subsets created, and
   * these subsets themselves occupy only a small constant amount of memory.
   *
   * @param set the set of elements to construct a power set from

			// we shouldn't remove it, and only remove the version instead
			return "", nil
		}
		return uuid.UUID(ver.ObjectV2.DataDir).String(), err
	}

	if fi.Deleted {
		err = x.addVersion(ventry)
		return "", err
	}
	return "", errFileVersionNotFound
}

// xlMetaDataDirDecoder is a shallow decoder for decoding object datadir only.
type xlMetaDataDirDecoder struct {

	}

	return s.readAllData(ctx, volume, volumeDir, filePath)
}

// ReadFile reads exactly len(buf) bytes into buf. It returns the
// number of bytes copied. The error is EOF only if no bytes were
// read. On return, n == len(buf) if and only if err == nil. n == 0
// for io.EOF.
//
// If an EOF happens after reading some but not all the bytes,
// ReadFile returns ErrUnexpectedEOF.
//

	if iamOS, ok := store.IAMStorageAPI.(*IAMObjectStore); ok {
		err := iamOS.loadAllFromObjStore(ctx, newCache, firstTime)
		if err != nil {
			return err
		}
	} else {
		// Only non-object IAM store (i.e. only etcd backend).
		bootstrapTraceMsgFirstTime("loading policy documents")
		if err := store.loadPolicyDocs(ctx, newCache.iamPolicyDocsMap); err != nil {
			return err
		}

     * is the only one in use, but if we encounter nested concatenations, we start a deque of
     * meta-iterators rather than letting the nesting get arbitrarily deep.  This keeps each
     * operation O(1).
     */

    private @Nullable Iterator<? extends Iterator<? extends T>> topMetaIterator;

    // Only becomes nonnull if we encounter nested concatenations.

     * ubiquitous protocols. Applications should only call this method to avoid specific
     * compatibility problems, such as web servers that behave incorrectly when HTTP/2 is enabled.
     *
     * The following protocols are currently supported:
     *
     * * [http/1.1][rfc_2616]
     * * [h2][rfc_7540]
     * * [h2 with prior knowledge(cleartext only)][rfc_7540_34]
     *

		if onlineDisk != nil && onlineDisk.IsOnline() {
			online++
		}
	}
	return online
}

// CopyObject - copy object source object to destination object.
// if source object and destination object are same we only
// update metadata.
func (er erasureObjects) CopyObject(ctx context.Context, srcBucket, srcObject, dstBucket, dstObject string, srcInfo ObjectInfo, srcOpts, dstOpts ObjectOptions) (oi ObjectInfo, err error) {
	if !dstOpts.NoAuditLog {

 * writes. The {@link Cache#cleanUp} method of the returned cache will also perform maintenance, but
 * calling it should not be necessary with a high throughput cache. Only caches built with {@link
 * #removalListener removalListener}, {@link #expireAfterWrite expireAfterWrite}, {@link
 * #expireAfterAccess expireAfterAccess}, {@link #weakKeys weakKeys}, {@link #weakValues