Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Protected Ctors](https://developer.android.com/reference/java/security/AlgorithmParameters#proctors) \| [Methods](https://developer.android.com/reference/java/security/AlgorithmParameters#pubmethods) \| [Inherited Methods](https://developer.android.com/reference/java/security/AlgorithmParameters#inhmethods)

# AlgorithmParameters


`
public


class
AlgorithmParameters
`


`

extends https://developer.android.com/reference/java/lang/Object


`

`


`

|---|---|
| [java.lang.Object](https://developer.android.com/reference/java/lang/Object) ||
| ↳ | java.security.AlgorithmParameters |

<br />

*** ** * ** ***

This class is used as an opaque representation of cryptographic parameters.

An `AlgorithmParameters` object for managing the parameters
for a particular algorithm can be obtained by
calling one of the `getInstance` factory methods
(static methods that return instances of a given class).

Once an `AlgorithmParameters` object is obtained, it must be
initialized via a call to `init`, using an appropriate parameter
specification or parameter encoding.

A transparent parameter specification is obtained from an
`AlgorithmParameters` object via a call to
`getParameterSpec`, and a byte encoding of the parameters is
obtained via a call to `getEncoded`.

Android provides the following `AlgorithmParameters` algorithms:

| Algorithm | Supported API Levels |
|---|---|
| AES | 1+ |
| BLOWFISH | 10+ |
| ChaCha20 | 28+ |
| DES | 1+ |
| DESede | 1+ |
| DH | 1+ |
| DSA | 1+ |
| EC | 26+ |
| GCM | 22+ |
| IES | 1-8 |
| OAEP | 1+ |
| PBEwithHmacSHA1AndAES_128 | 26+ |
| PBEwithHmacSHA1AndAES_256 | 26+ |
| PBEwithHmacSHA224AndAES_128 | 26+ |
| PBEwithHmacSHA224AndAES_256 | 26+ |
| PBEwithHmacSHA256AndAES_128 | 26+ |
| PBEwithHmacSHA256AndAES_256 | 26+ |
| PBEwithHmacSHA384AndAES_128 | 26+ |
| PBEwithHmacSHA384AndAES_256 | 26+ |
| PBEwithHmacSHA512AndAES_128 | 26+ |
| PBEwithHmacSHA512AndAES_256 | 26+ |
| PKCS12PBE | 1+ |
| PSS | 1-8,24+ |

<br />

**See also:**

- `https://developer.android.com/reference/java/security/spec/AlgorithmParameterSpec`
- `https://developer.android.com/reference/java/security/spec/DSAParameterSpec`
- `https://developer.android.com/reference/java/security/KeyPairGenerator`

## Summary

| ### Protected constructors ||
|---|---|
| ` https://developer.android.com/reference/java/security/AlgorithmParameters#AlgorithmParameters(java.security.AlgorithmParametersSpi,%20java.security.Provider,%20java.lang.String)(https://developer.android.com/reference/java/security/AlgorithmParametersSpi paramSpi, https://developer.android.com/reference/java/security/Provider provider, https://developer.android.com/reference/java/lang/String algorithm) ` Creates an AlgorithmParameters object. |

| ### Public methods ||
|---|---|
| ` final https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#getAlgorithm()() ` Returns the name of the algorithm associated with this parameter object. |
| ` final byte[]` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#getEncoded(java.lang.String)(https://developer.android.com/reference/java/lang/String format) ` Returns the parameters encoded in the specified scheme. |
| ` final byte[]` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#getEncoded()() ` Returns the parameters in their primary encoding format. |
| ` static https://developer.android.com/reference/java/security/AlgorithmParameters` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#getInstance(java.lang.String)(https://developer.android.com/reference/java/lang/String algorithm) ` Returns a parameter object for the specified algorithm. |
| ` static https://developer.android.com/reference/java/security/AlgorithmParameters` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#getInstance(java.lang.String,%20java.lang.String)(https://developer.android.com/reference/java/lang/String algorithm, https://developer.android.com/reference/java/lang/String provider) ` Returns a parameter object for the specified algorithm. |
| ` static https://developer.android.com/reference/java/security/AlgorithmParameters` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#getInstance(java.lang.String,%20java.security.Provider)(https://developer.android.com/reference/java/lang/String algorithm, https://developer.android.com/reference/java/security/Provider provider) ` Returns a parameter object for the specified algorithm. |
| ` final <T extends https://developer.android.com/reference/java/security/spec/AlgorithmParameterSpec> T` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#getParameterSpec(java.lang.Class<T>)(https://developer.android.com/reference/java/lang/Class<T> paramSpec) ` Returns a (transparent) specification of this parameter object. |
| ` final https://developer.android.com/reference/java/security/Provider` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#getProvider()() ` Returns the provider of this parameter object. |
| ` final void` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#init(byte[])(byte[] params) ` Imports the specified parameters and decodes them according to the primary decoding format for parameters. |
| ` final void` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#init(java.security.spec.AlgorithmParameterSpec)(https://developer.android.com/reference/java/security/spec/AlgorithmParameterSpec paramSpec) ` Initializes this parameter object using the parameters specified in `paramSpec`. |
| ` final void` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#init(byte[],%20java.lang.String)(byte[] params, https://developer.android.com/reference/java/lang/String format) ` Imports the parameters from `params` and decodes them according to the specified decoding scheme. |
| ` final https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/java/security/AlgorithmParameters#toString()() ` Returns a formatted string describing the parameters. |

| ### 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*. | ||

## Protected constructors

### AlgorithmParameters

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
protected AlgorithmParameters (AlgorithmParametersSpi paramSpi, 
                Provider provider, 
                String algorithm)
```

Creates an AlgorithmParameters object.

<br />

| Parameters ||
|---|---|
| `paramSpi` | `AlgorithmParametersSpi`: the delegate <br /> |
| `provider` | `Provider`: the provider <br /> |
| `algorithm` | `String`: the algorithm <br /> |

## Public methods

### getAlgorithm

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final String getAlgorithm ()
```

Returns the name of the algorithm associated with this parameter object.

<br />

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/lang/String` | the algorithm name. <br /> |

### getEncoded

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final byte[] getEncoded (String format)
```

Returns the parameters encoded in the specified scheme.
If `format` is null, the
primary encoding format for parameters is used. The primary encoding
format is ASN.1, if an ASN.1 specification for these parameters
exists.

<br />

| Parameters ||
|---|---|
| `format` | `String`: the name of the encoding format. <br /> |

| Returns ||
|---|---|
| `byte[]` | the parameters encoded using the specified encoding scheme. <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | on encoding errors, or if this parameter object has not been initialized. |

### getEncoded

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final byte[] getEncoded ()
```

Returns the parameters in their primary encoding format.
The primary encoding format for parameters is ASN.1, if an ASN.1
specification for this type of parameters exists.

<br />

| Returns ||
|---|---|
| `byte[]` | the parameters encoded using their primary encoding format. <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | on encoding errors, or if this parameter object has not been initialized. |

### getInstance

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public static AlgorithmParameters getInstance (String algorithm)
```

Returns a parameter object for the specified algorithm.

This method traverses the list of registered security Providers,
starting with the most preferred Provider.
A new AlgorithmParameters object encapsulating the
AlgorithmParametersSpi implementation from the first
Provider that supports the specified algorithm is returned.

Note that the list of registered providers may be retrieved via
the `https://developer.android.com/reference/java/security/Security#getProviders()` method.

The returned parameter object must be initialized via a call to
`init`, using an appropriate parameter specification or
parameter encoding.

<br />

| Parameters ||
|---|---|
| `algorithm` | `String`: the name of the algorithm requested. <br /> |

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/security/AlgorithmParameters` | the new parameter object <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/lang/NullPointerException` | if `algorithm` is `null` on Android 14 or above |
| `https://developer.android.com/reference/java/security/NoSuchAlgorithmException` | if no `Provider` supports an `AlgorithmParametersSpi` implementation for the specified algorithm |

**See also:**

- `https://developer.android.com/reference/java/security/Provider`

### getInstance

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public static AlgorithmParameters getInstance (String algorithm, 
                String provider)
```

Returns a parameter object for the specified algorithm.

A new AlgorithmParameters object encapsulating the
AlgorithmParametersSpi implementation from the specified provider
is returned. The specified provider must be registered
in the security provider list.

Note that the list of registered providers may be retrieved via
the `https://developer.android.com/reference/java/security/Security#getProviders()` method.

The returned parameter object must be initialized via a call to
`init`, using an appropriate parameter specification or
parameter encoding.

<br />

| Parameters ||
|---|---|
| `algorithm` | `String`: the name of the algorithm requested. <br /> |
| `provider` | `String`: the name of the provider. <br /> |

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/security/AlgorithmParameters` | the new parameter object <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/lang/IllegalArgumentException` | if the provider name is `null` or empty |
| `https://developer.android.com/reference/java/lang/NullPointerException` | if `algorithm` is `null` on Android 14 or above |
| `https://developer.android.com/reference/java/security/NoSuchAlgorithmException` | if an `AlgorithmParametersSpi` implementation for the specified algorithm is not available from the specified provider |
| `https://developer.android.com/reference/java/security/NoSuchProviderException` | if the specified provider is not registered in the security provider list |

**See also:**

- `https://developer.android.com/reference/java/security/Provider`

### getInstance

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public static AlgorithmParameters getInstance (String algorithm, 
                Provider provider)
```

Returns a parameter object for the specified algorithm.

A new AlgorithmParameters object encapsulating the
AlgorithmParametersSpi implementation from the specified Provider
object is returned. Note that the specified Provider object
does not have to be registered in the provider list.

The returned parameter object must be initialized via a call to
`init`, using an appropriate parameter specification or
parameter encoding.

<br />

| Parameters ||
|---|---|
| `algorithm` | `String`: the name of the algorithm requested. <br /> |
| `provider` | `Provider`: the name of the provider. <br /> |

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/security/AlgorithmParameters` | the new parameter object <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/lang/IllegalArgumentException` | if the provider is `null` |
| `https://developer.android.com/reference/java/lang/NullPointerException` | if `algorithm` is `null` on Android 14 or above |
| `https://developer.android.com/reference/java/security/NoSuchAlgorithmException` | if an `AlgorithmParameterGeneratorSpi` implementation for the specified algorithm is not available from the specified `Provider` object |

**See also:**

- `https://developer.android.com/reference/java/security/Provider`

### getParameterSpec

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final T getParameterSpec (Class<T> paramSpec)
```

Returns a (transparent) specification of this parameter object.
`paramSpec` identifies the specification class in which
the parameters should be returned. It could, for example, be
`DSAParameterSpec.class`, to indicate that the
parameters should be returned in an instance of the
`DSAParameterSpec` class.

<br />

| Parameters ||
|---|---|
| `paramSpec` | `Class`: the specification class in which the parameters should be returned. <br /> |

| Returns ||
|---|---|
| `T` | the parameter specification. <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/security/spec/InvalidParameterSpecException` | if the requested parameter specification is inappropriate for this parameter object, or if this parameter object has not been initialized. |

### getProvider

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final Provider getProvider ()
```

Returns the provider of this parameter object.

<br />

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/security/Provider` | the provider of this parameter object <br /> |

### init

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final void init (byte[] params)
```

Imports the specified parameters and decodes them according to the
primary decoding format for parameters. The primary decoding
format for parameters is ASN.1, if an ASN.1 specification for this type
of parameters exists.

<br />

| Parameters ||
|---|---|
| `params` | `byte`: the encoded parameters. <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | on decoding errors, or if this parameter object has already been initialized. |

### init

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final void init (AlgorithmParameterSpec paramSpec)
```

Initializes this parameter object using the parameters
specified in `paramSpec`.

<br />

| Parameters ||
|---|---|
| `paramSpec` | `AlgorithmParameterSpec`: the parameter specification. <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/security/spec/InvalidParameterSpecException` | if the given parameter specification is inappropriate for the initialization of this parameter object, or if this parameter object has already been initialized. |

### init

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final void init (byte[] params, 
                String format)
```

Imports the parameters from `params` and decodes them
according to the specified decoding scheme.
If `format` is null, the
primary decoding format for parameters is used. The primary decoding
format is ASN.1, if an ASN.1 specification for these parameters
exists.

<br />

| Parameters ||
|---|---|
| `params` | `byte`: the encoded parameters. <br /> |
| `format` | `String`: the name of the decoding scheme. <br /> |

| Throws ||
|---|---|
| `https://developer.android.com/reference/java/io/IOException` | on decoding errors, or if this parameter object has already been initialized. |

### toString

Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)

```
public final String toString ()
```

Returns a formatted string describing the parameters.

<br />

| Returns ||
|---|---|
| `https://developer.android.com/reference/java/lang/String` | a formatted string describing the parameters, or null if this parameter object has not been initialized. <br /> |