### Set legal hold on an object

PutObject API allows setting legal hold using `x-amz-object-lock-legal-hold` header.

```sh
aws s3api put-object --bucket testbucket --key legalhold --object-lock-legal-hold-status ON --body /etc/issue
```

		mode = RetCompliance
	}
	return mode
}

// LegalHoldStatus - object legal hold status.
type LegalHoldStatus string

const (
	// LegalHoldOn - legal hold is on.
	LegalHoldOn LegalHoldStatus = "ON"

	// LegalHoldOff - legal hold is off.
	LegalHoldOff LegalHoldStatus = "OFF"
)

// Valid - returns true if legal hold status has valid values
func (l LegalHoldStatus) Valid() bool {
	switch l {

This lock guards internal state of each connection. This lock is never held for blocking operations. That means that we acquire the lock, read or write a few fields and release the lock. No I/O and no application-layer callbacks.

#### Http2Stream

		{
			metadata: map[string]string{
				"x-amz-object-lock-legal-hold": "on",
			},
			expected: ObjectLegalHold{Status: LegalHoldOn},
		},
		{
			metadata: map[string]string{
				"x-amz-object-lock-legal-hold": "off",
			},
			expected: ObjectLegalHold{Status: LegalHoldOff},
		},
		{
			metadata: map[string]string{
				"x-amz-object-lock-legal-hold": "X",
			},
			expected: ObjectLegalHold{Status: ""},
		},

   * implementation, because {@code map.get()} returns a view collection that changes in the course
   * of a call to {@code remove()}. Thus, the expectation doesn't hold that {@code map.remove(x)}
   * returns the same value which {@code map.get(x)} did immediately beforehand.
   */
  @Override
  public void testRemove() {
    final Map<String, Collection<Integer>> map;

func enforceRetentionForDeletion(ctx context.Context, objInfo ObjectInfo) (locked bool) {
	if objInfo.DeleteMarker {
		return false
	}

	lhold := objectlock.GetObjectLegalHoldMeta(objInfo.UserDefined)
	if lhold.Status.Valid() && lhold.Status == objectlock.LegalHoldOn {
		return true
	}

	ret := objectlock.GetObjectRetentionMeta(objInfo.UserDefined)

    throw AssertionError("Thread ${Thread.currentThread().name} MUST hold lock on $this")
  }
}

@Suppress("NOTHING_TO_INLINE")
internal inline fun Any.assertThreadHoldsLock() {
  if (assertionsEnabled && !Thread.holdsLock(this)) {
    throw AssertionError("Thread ${Thread.currentThread().name} MUST hold lock on $this")
  }
}

@Suppress("NOTHING_TO_INLINE")

	}
	ps.Lock()
	defer ps.Unlock()

	sub := &Sub[T]{ch: subCh, types: Mask(mask.Mask()), filter: filter}
	ps.subs = append(ps.subs, sub)

	// We hold a lock, so we are safe to update
	combined := Mask(atomic.LoadUint64(&ps.types))
	combined.Merge(Mask(mask.Mask()))
	atomic.StoreUint64(&ps.types, uint64(combined))

	go func() {
		<-doneCh

		ps.Lock()

      ArrayListMultimap<K, V> create() {
    return new ArrayListMultimap<>();
  }

  /**
   * Constructs an empty {@code ArrayListMultimap} with enough capacity to hold the specified
   * numbers of keys and values without resizing.
   *
   * <p>This method will soon be deprecated in favor of {@code
   * MultimapBuilder.hashKeys(expectedKeys).arrayListValues(expectedValuesPerKey).build()}.

   * execution consists of blocking until the input future is {@linkplain Future#isDone() done}, so
   * each call to this method may claim and hold a thread for an arbitrary length of time. Use of
   * bounded executors or other executors that may fail to execute a task promptly may result in
   * deadlocks.
   *