Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Nested Classes](https://developer.android.com/reference/android/crypto/hpke/Recipient#nestedclasses) \| [Methods](https://developer.android.com/reference/android/crypto/hpke/Recipient#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/android/crypto/hpke/Recipient#inhmethods)

# Recipient

*** ** * ** ***

` public class Recipient `   
` extends https://developer.android.com/reference/java/lang/Object ` ` `

|---|---|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||
| ↳ | android.crypto.hpke.Recipient |

<br />

*** ** * ** ***

A class for receiving HPKE messages.

## Summary

| ### Nested classes ||
|---|---|
| ` class` | `https://developer.android.com/reference/android/crypto/hpke/Recipient.Builder` A builder for HPKE Recipient objects. |

| ### Public methods ||
|---|---|
| ` byte[]` | ` https://developer.android.com/reference/android/crypto/hpke/Recipient#export(int,%20byte[])(int length, byte[] context) ` Exports secret key material from this Recipient as described in RFC 9180. |
| ` https://developer.android.com/reference/java/security/Provider` | ` https://developer.android.com/reference/android/crypto/hpke/Recipient#getProvider()() ` Returns the `https://developer.android.com/reference/java/security/Provider` being used by this Recipient. |
| ` https://developer.android.com/reference/android/crypto/hpke/HpkeSpi` | ` https://developer.android.com/reference/android/crypto/hpke/Recipient#getSpi()() ` Returns the `https://developer.android.com/reference/android/crypto/hpke/HpkeSpi` being used by this Recipient. |
| ` byte[]` | ` https://developer.android.com/reference/android/crypto/hpke/Recipient#open(byte[],%20byte[])(byte[] ciphertext, byte[] aad) ` Opens a message, using the internal key schedule maintained by this Recipient. |

### Inherited methods

From class ` https://developer.android.com/reference/java/lang/Object ` ` https://developer.android.com/reference/java/lang/Object` ` https://developer.android.com/reference/java/lang/Object#clone()() `

Creates and returns a copy of this object.
` boolean` ` https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) `

Indicates whether some other object is "equal to" this one.
` void` ` https://developer.android.com/reference/java/lang/Object#finalize()() `

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
` final https://developer.android.com/reference/java/lang/Class<?>` ` https://developer.android.com/reference/java/lang/Object#getClass()() `

Returns the runtime class of this `Object`.
` int` ` https://developer.android.com/reference/java/lang/Object#hashCode()() `

Returns a hash code value for the object.
` final void` ` https://developer.android.com/reference/java/lang/Object#notify()() `

Wakes up a single thread that is waiting on this object's monitor.
` final void` ` https://developer.android.com/reference/java/lang/Object#notifyAll()() `

Wakes up all threads that are waiting on this object's monitor.
` https://developer.android.com/reference/java/lang/String` ` https://developer.android.com/reference/java/lang/Object#toString()() `

Returns a string representation of the object.
` final void` ` https://developer.android.com/reference/java/lang/Object#wait(long,%20int)(long timeoutMillis, int nanos) `

Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed.
` final void` ` https://developer.android.com/reference/java/lang/Object#wait(long)(long timeoutMillis) `

Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed.
` final void` ` https://developer.android.com/reference/java/lang/Object#wait()() `

Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*.

## Public methods

### export

Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public byte[] export (int length, 
                byte[] context)
```

Exports secret key material from this Recipient as described in RFC 9180.

<br />

| Parameters ||
|---|---|
| `length` | `int`: expected output length <br /> |
| `context` | `byte`: optional exporter context string, may be null or empty <br /> |

| Returns ||
|---|---|
| `byte[]` | exported value. This value cannot be `null`. <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/lang/IllegalArgumentException` | if the length is not valid for the KDF in use |

### getProvider

Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public Provider getProvider ()
```

Returns the `https://developer.android.com/reference/java/security/Provider` being used by this Recipient.

<br />

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/security/Provider` | the Provider. This value cannot be `null`. <br /> |

### getSpi

Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public HpkeSpi getSpi ()
```

Returns the `https://developer.android.com/reference/android/crypto/hpke/HpkeSpi` being used by this Recipient.

<br />

| Returns ||
|---|---|
| `https://developer.android.com/reference/android/crypto/hpke/HpkeSpi` | the SPI. This value cannot be `null`. <br /> |

### open

Added in [API level 37](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public byte[] open (byte[] ciphertext, 
                byte[] aad)
```

Opens a message, using the internal key schedule maintained by this Recipient.

<br />

| Parameters ||
|---|---|
| `ciphertext` | `byte`: the ciphertext. This value cannot be `null`. <br /> |
| `aad` | `byte`: optional additional authenticated data, may be null or empty <br /> |

| Returns ||
|---|---|
| `byte[]` | the plaintext. This value cannot be `null`. <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/security/GeneralSecurityException` | on decryption failures |

**See also:**

- [Opening and sealing](https://www.rfc-editor.org/rfc/rfc9180.html#name-encryption-and-decryption-2)