}

  /**
   * Combines four iterators into a single iterator. The returned iterator iterates across the
   * elements in {@code a}, followed by the elements in {@code b}, followed by the elements in
   * {@code c}, followed by the elements in {@code d}. The source iterators are not polled until
   * necessary.
   *

) {
	anonTestStr := "Anonymous HTTP request test"
	unknownSignTestStr := "Unknown HTTP signature test"

	// simple function which returns a message which gives the context of the test
	// and then followed by the actual error message.
	failTestStr := func(testType, failMsg string) string {
		return fmt.Sprintf("MinIO %s: %s fail for \"%s\": \n<Error> %s", instanceType, testType, testName, failMsg)
	}

    }
  }

  /**
   * Returns an immutable set instance containing the given enum elements. Internally, the returned
   * set will be backed by an {@link EnumSet}.
   *
   * <p>The iteration order of the returned set follows the enum's iteration order, not the order in
   * which the elements are provided to the method.
   *
   * @param anElement one of the elements the set should contain

    // protocol for completing a future is to assign the value field (which sets isDone to true) and
    // then to release waiters, followed by executing afterDone(), followed by releasing listeners.
    // That means that it is possible to observe that the future isDone and that your listeners
    // don't execute 'immediately'.  By checking isDone here we avoid that.

   *   Iterator<V> i = values.iterator(); // Must be in synchronized block
   *   while (i.hasNext()) {
   *     foo(i.next());
   *   }
   * }
   * }</pre>
   *
   * <p>Failure to follow this advice may result in non-deterministic behavior.
   *
   * <p>Note that the generated multimap's {@link Multimap#removeAll} and {@link
   * Multimap#replaceValues} methods return collections that aren't synchronized.

		v := strings.ToLower(vs)
		switch v {
		case "true", "false":
			objectLockEnabled = v == "true"
		default:
			writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrInvalidRequest), r.URL)
			return
		}
	}

	forceCreate := false
	if vs := r.Header.Get(xhttp.MinIOForceCreate); len(vs) > 0 {
		v := strings.ToLower(vs)
		switch v {
		case "true", "false":

	for k, v := range objInfo.Metadata {
		oi.UserDefined[k] = v[0]
	}

	ce, ok := oi.UserDefined[xhttp.ContentEncoding]
	if !ok {
		ce, ok = oi.UserDefined[strings.ToLower(xhttp.ContentEncoding)]
	}
	if ok {
		oi.ContentEncoding = ce
	}

	_, ok = oi.UserDefined[xhttp.AmzStorageClass]
	if !ok {
		oi.UserDefined[xhttp.AmzStorageClass] = objInfo.StorageClass
	}

 * equals</i>. That is, {@code a.compareTo(b)} or {@code comparator.compare(a, b)} should equal zero
 * <i>if and only if</i> {@code a.equals(b)}. If this advice is not followed, the resulting map will
 * not correctly obey its specification.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *

			Object: object,
		}
	}

	if opts.DeletePrefix {
		if opts.Expiration.Expire {
			// Expire all versions expiration must still verify the state() on disk
			// via a getObjectInfo() call as follows, any read quorum issues we
			// must not proceed further for safety reasons. attempt a MRF heal
			// while we see such quorum errors.
			goi, _, gerr := er.getObjectInfoAndQuorum(ctx, bucket, object, opts)

		// as a List() call is an important performance improvement.
		//
		// Spark based s3a committers are a  big enough use-case to have this optimization.
		//
		// A sample code to see the improvements is as follows, this sample code is
		// simply a read on JSON from MinIO and write it back as "parquet".
		//
		// import org.apache.spark.sql.SparkSession