func (t *Transition) UnmarshalXML(d *xml.Decoder, startElement xml.StartElement) error {
	type transitionWrapper Transition
	var trw transitionWrapper
	err := d.DecodeElement(&trw, &startElement)
	if err != nil {
		return err
	}
	*t = Transition(trw)
	t.set = true
	return nil
}

// Validate - validates the "Transition" element
func (t Transition) Validate() error {
	if !t.set {

// license that can be found in the LICENSE file.

package template

import (
	"bytes"
	"strings"
)

// transitionFunc is the array of context transition functions for text nodes.
// A transition function takes a context and template text input, and returns
// the updated context and the number of bytes consumed from the front of the
// input.

        public Trie build() {
            Trie[] transitions = new Trie[this.transitions.size()];
            for (int i = 0; i < this.transitions.size(); i++) {
                Builder transition = this.transitions.get(i);
                transitions[i] = transition.build();
            }
            Arrays.sort(transitions);
            return new Trie(c, terminal, transitions);
        }
    }

            controller.transition(TestState.A, TestState.B, action)
        }

        then:
        def e = thrown(IllegalStateException)
        e.message == "Cannot transition <state> to state B as already transitioning to this state."

        1 * action.run() >> {
            controller.transition(TestState.A, TestState.B, {})
        }
        0 * _
    }

Lifecycle transition rules can be applied to buckets (both versioned and un-versioned) by specifying the tier name defined above as the transition storage class for the lifecycle rule.

## Implementation

}

// ExpectedExpiryTime calculates the expiry, transition or restore date/time based on a object modtime.
// The expected transition or restore time is always a midnight time following the object
// modification time plus the number of transition/restore days.
//
//	e.g. If the object modtime is `Thu May 21 13:42:50 GMT 2020` and the object should
//	    transition in 1 day, then the expected transition time is `Fri, 23 May 2020 00:00:00 GMT`

// purposes. For example, on POSIX-y operating systems, Reserved is usually a
// private anonymous mmap'd region with PROT_NONE set, and to transition
// to Ready would require setting PROT_READ|PROT_WRITE. However the
// underspecification of Prepared lets us use just MADV_FREE to transition from
// Ready to Prepared. Thus with the Prepared state we can set the permission
// bits just once early on, we can efficiently tell the OS that it's free to

		err   error
	}{
		{
			input: `<Transition>
			<Days>0</Days>
			<StorageClass>S3TIER-1</StorageClass>
		  </Transition>`,
			err: nil,
		},
		{
			input: `<Transition>
			<Days>1</Days>
			<Date>2021-01-01T00:00:00Z</Date>
			<StorageClass>S3TIER-1</StorageClass>
		  </Transition>`,
			err: errTransitionInvalid,
		},
		{
			input: `<Transition>
			<Days>1</Days>
		  </Transition>`,

--restore-request Days=3
```

### 4.1 Monitoring transition events

`s3:ObjectTransition:Complete` and `s3:ObjectTransition:Failed` events can be used to monitor transition events between the source cluster and transition tier. To watch lifecycle events, you can enable bucket notification on the source bucket with `mc event add`  and specify `--event ilm` flag.

Note that transition event notification is a MinIO extension.

## Explore Further

## Add warm tier
./mc ilm tier add minio sitea WARM-TIER --endpoint http://localhost:9006 --access-key minio --secret-key minio123 --bucket bucket

## Add ILM rules
./mc ilm add sitea/bucket --transition-days 0 --transition-tier WARM-TIER --transition-days 0 --noncurrent-expire-days 2 --expire-days 3 --prefix "myprefix" --tags "tag1=val1&tag2=val2"
./mc ilm rule list sitea/bucket

## Check ilm expiry flag
./mc admin replicate info sitea --json