Uses of Interface java.security.Key (Java Platform SE 8 )
Date: 2026-08-19

## Uses of Interface
java.security.Key

- Packages that use Key
  Package | Description
  --- | ---
  java.security | Provides the classes and interfaces for the security framework.
  java.security.interfaces | Provides interfaces for generating RSA (Rivest, Shamir and Adleman AsymmetricCipher algorithm) keys as defined in the RSA Laboratory Technical Note PKCS#1, and DSA (Digital Signature Algorithm) keys as defined in NIST's FIPS-186.
  javax.crypto | Provides the classes and interfaces for cryptographic operations.
  javax.crypto.interfaces | Provides interfaces for Diffie-Hellman keys as defined in RSA Laboratories' PKCS #3.
  javax.crypto.spec | Provides classes and interfaces for key specifications and algorithm parameter specifications.
  javax.security.auth.kerberos | This package contains utility classes related to the Kerberos network authentication protocol.
  javax.xml.crypto | Common classes for XML cryptography.
  javax.xml.crypto.dsig.dom | DOM-specific classes for the `javax.xml.crypto.dsig` package.

- - ### Uses of Key in java.security

    Subinterfaces of Key in java.security
    Modifier and Type | Interface and Description
    --- | ---
    `interface` | `PrivateKey` A private key.
    `interface` | `PublicKey` A public key.

    Methods in java.security that return Key
    Modifier and Type | Method and Description
    --- | ---
    `abstract Key` | KeyStoreSpi.`engineGetKey(String alias, char[] password)` Returns the key associated with the given alias, using the given password to recover it.
    `protected abstract Key` | KeyFactorySpi.`engineTranslateKey(Key key)` Translates a key object, whose provider may be unknown or potentially untrusted, into a corresponding key object of this key factory.
    `Key` | KeyStore.`getKey(String alias, char[] password)` Returns the key associated with the given alias, using the given password to recover it.
    `Key` | KeyFactory.`translateKey(Key key)` Translates a key object, whose provider may be unknown or potentially untrusted, into a corresponding key object of this key factory.

    Methods in java.security with parameters of type Key
    Modifier and Type | Method and Description
    --- | ---
    `protected abstract <T extends KeySpec> T` | KeyFactorySpi.`engineGetKeySpec(Key key, Class<T> keySpec)` Returns a specification (key material) of the given key object.
    `abstract void` | KeyStoreSpi.`engineSetKeyEntry(String alias, Key key, char[] password, Certificate[] chain)` Assigns the given key to the given alias, protecting it with the given password.
    `protected abstract Key` | KeyFactorySpi.`engineTranslateKey(Key key)` Translates a key object, whose provider may be unknown or potentially untrusted, into a corresponding key object of this key factory.
    `<T extends KeySpec> T` | KeyFactory.`getKeySpec(Key key, Class<T> keySpec)` Returns a specification (key material) of the given key object.
    `boolean` | AlgorithmConstraints.`permits(Set<CryptoPrimitive> primitives, Key key)` Determines whether a key is granted permission for the specified cryptographic primitives.
    `boolean` | AlgorithmConstraints.`permits(Set<CryptoPrimitive> primitives, String algorithm, Key key, AlgorithmParameters parameters)` Determines whether an algorithm and the corresponding key are granted permission for the specified cryptographic primitives.
    `void` | KeyStore.`setKeyEntry(String alias, Key key, char[] password, Certificate[] chain)` Assigns the given key to the given alias, protecting it with the given password.
    `Key` | KeyFactory.`translateKey(Key key)` Translates a key object, whose provider may be unknown or potentially untrusted, into a corresponding key object of this key factory.

  - ### Uses of Key in java.security.interfaces

    Subinterfaces of Key in java.security.interfaces
    Modifier and Type | Interface and Description
    --- | ---
    `interface` | `DSAPrivateKey` The standard interface to a DSA private key.
    `interface` | `DSAPublicKey` The interface to a DSA public key.
    `interface` | `ECPrivateKey` The interface to an elliptic curve (EC) private key.
    `interface` | `ECPublicKey` The interface to an elliptic curve (EC) public key.
    `interface` | `RSAMultiPrimePrivateCrtKey` The interface to an RSA multi-prime private key, as defined in the PKCS#1 v2.2 standard, using the Chinese Remainder Theorem (CRT) information values.
    `interface` | `RSAPrivateCrtKey` The interface to an RSA private key, as defined in the PKCS#1 v2.2 standard, using the Chinese Remainder Theorem (CRT) information values.
    `interface` | `RSAPrivateKey` The interface to an RSA private key.
    `interface` | `RSAPublicKey` The interface to an RSA public key.

  - ### Uses of Key in javax.crypto

    Subinterfaces of Key in javax.crypto
    Modifier and Type | Interface and Description
    --- | ---
    `interface` | `SecretKey` A secret (symmetric) key.

    Methods in javax.crypto that return Key
    Modifier and Type | Method and Description
    --- | ---
    `Key` | KeyAgreement.`doPhase(Key key, boolean lastPhase)` Executes the next phase of this key agreement with the given key that was received from one of the other parties involved in this key agreement.
    `protected abstract Key` | KeyAgreementSpi.`engineDoPhase(Key key, boolean lastPhase)` Executes the next phase of this key agreement with the given key that was received from one of the other parties involved in this key agreement.
    `protected Key` | CipherSpi.`engineUnwrap(byte[] wrappedKey, String wrappedKeyAlgorithm, int wrappedKeyType)` Unwrap a previously wrapped key.
    `Key` | Cipher.`unwrap(byte[] wrappedKey, String wrappedKeyAlgorithm, int wrappedKeyType)` Unwrap a previously wrapped key.

    Methods in javax.crypto with parameters of type Key
    Modifier and Type | Method and Description
    --- | ---
    `Key` | KeyAgreement.`doPhase(Key key, boolean lastPhase)` Executes the next phase of this key agreement with the given key that was received from one of the other parties involved in this key agreement.
    `protected abstract Key` | KeyAgreementSpi.`engineDoPhase(Key key, boolean lastPhase)` Executes the next phase of this key agreement with the given key that was received from one of the other parties involved in this key agreement.
    `protected int` | CipherSpi.`engineGetKeySize(Key key)` Returns the key size of the given key object in bits.
    `protected abstract void` | CipherSpi.`engineInit(int opmode, Key key, AlgorithmParameterSpec params, SecureRandom random)` Initializes this cipher with a key, a set of algorithm parameters, and a source of randomness.
    `protected abstract void` | CipherSpi.`engineInit(int opmode, Key key, AlgorithmParameters params, SecureRandom random)` Initializes this cipher with a key, a set of algorithm parameters, and a source of randomness.
    `protected abstract void` | CipherSpi.`engineInit(int opmode, Key key, SecureRandom random)` Initializes this cipher with a key and a source of randomness.
    `protected abstract void` | ExemptionMechanismSpi.`engineInit(Key key)` Initializes this exemption mechanism with a key.
    `protected abstract void` | ExemptionMechanismSpi.`engineInit(Key key, AlgorithmParameters params)` Initializes this exemption mechanism with a key and a set of algorithm parameters.
    `protected abstract void` | MacSpi.`engineInit(Key key, AlgorithmParameterSpec params)` Initializes the MAC with the given (secret) key and algorithm parameters.
    `protected abstract void` | ExemptionMechanismSpi.`engineInit(Key key, AlgorithmParameterSpec params)` Initializes this exemption mechanism with a key and a set of algorithm parameters.
    `protected abstract void` | KeyAgreementSpi.`engineInit(Key key, AlgorithmParameterSpec params, SecureRandom random)` Initializes this key agreement with the given key, set of algorithm parameters, and source of randomness.
    `protected abstract void` | KeyAgreementSpi.`engineInit(Key key, SecureRandom random)` Initializes this key agreement with the given key and source of randomness.
    `protected byte[]` | CipherSpi.`engineWrap(Key key)` Wrap a key.
    `PKCS8EncodedKeySpec` | EncryptedPrivateKeyInfo.`getKeySpec(Key decryptKey)` Extract the enclosed PKCS8EncodedKeySpec object from the encrypted data and return it.
    `PKCS8EncodedKeySpec` | EncryptedPrivateKeyInfo.`getKeySpec(Key decryptKey, Provider provider)` Extract the enclosed PKCS8EncodedKeySpec object from the encrypted data and return it.
    `PKCS8EncodedKeySpec` | EncryptedPrivateKeyInfo.`getKeySpec(Key decryptKey, String providerName)` Extract the enclosed PKCS8EncodedKeySpec object from the encrypted data and return it.
    `Object` | SealedObject.`getObject(Key key)` Retrieves the original (encapsulated) object.
    `Object` | SealedObject.`getObject(Key key, String provider)` Retrieves the original (encapsulated) object.
    `void` | Cipher.`init(int opmode, Key key)` Initializes this cipher with a key.
    `void` | Cipher.`init(int opmode, Key key, AlgorithmParameters params)` Initializes this cipher with a key and a set of algorithm parameters.
    `void` | Cipher.`init(int opmode, Key key, AlgorithmParameterSpec params)` Initializes this cipher with a key and a set of algorithm parameters.
    `void` | Cipher.`init(int opmode, Key key, AlgorithmParameterSpec params, SecureRandom random)` Initializes this cipher with a key, a set of algorithm parameters, and a source of randomness.
    `void` | Cipher.`init(int opmode, Key key, AlgorithmParameters params, SecureRandom random)` Initializes this cipher with a key, a set of algorithm parameters, and a source of randomness.
    `void` | Cipher.`init(int opmode, Key key, SecureRandom random)` Initializes this cipher with a key and a source of randomness.
    `void` | Mac.`init(Key key)` Initializes this `Mac` object with the given key.
    `void` | KeyAgreement.`init(Key key)` Initializes this key agreement with the given key, which is required to contain all the algorithm parameters required for this key agreement.
    `void` | ExemptionMechanism.`init(Key key)` Initializes this exemption mechanism with a key.
    `void` | ExemptionMechanism.`init(Key key, AlgorithmParameters params)` Initializes this exemption mechanism with a key and a set of algorithm parameters.
    `void` | Mac.`init(Key key, AlgorithmParameterSpec params)` Initializes this `Mac` object with the given key and algorithm parameters.
    `void` | KeyAgreement.`init(Key key, AlgorithmParameterSpec params)` Initializes this key agreement with the given key and set of algorithm parameters.
    `void` | ExemptionMechanism.`init(Key key, AlgorithmParameterSpec params)` Initializes this exemption mechanism with a key and a set of algorithm parameters.
    `void` | KeyAgreement.`init(Key key, AlgorithmParameterSpec params, SecureRandom random)` Initializes this key agreement with the given key, set of algorithm parameters, and source of randomness.
    `void` | KeyAgreement.`init(Key key, SecureRandom random)` Initializes this key agreement with the given key and source of randomness.
    `boolean` | ExemptionMechanism.`isCryptoAllowed(Key key)` Returns whether the result blob has been generated successfully by this exemption mechanism.
    `byte[]` | Cipher.`wrap(Key key)` Wrap a key.

  - ### Uses of Key in javax.crypto.interfaces

    Subinterfaces of Key in javax.crypto.interfaces
    Modifier and Type | Interface and Description
    --- | ---
    `interface` | `DHPrivateKey` The interface to a Diffie-Hellman private key.
    `interface` | `DHPublicKey` The interface to a Diffie-Hellman public key.
    `interface` | `PBEKey` The interface to a PBE key.

  - ### Uses of Key in javax.crypto.spec

    Classes in javax.crypto.spec that implement Key
    Modifier and Type | Class and Description
    --- | ---
    `class` | `SecretKeySpec` This class specifies a secret key in a provider-independent fashion.

  - ### Uses of Key in javax.security.auth.kerberos

    Classes in javax.security.auth.kerberos that implement Key
    Modifier and Type | Class and Description
    --- | ---
    `class` | `KerberosKey` This class encapsulates a long term secret key for a Kerberos principal.

  - ### Uses of Key in javax.xml.crypto

    Methods in javax.xml.crypto that return Key
    Modifier and Type | Method and Description
    --- | ---
    `Key` | KeySelectorResult.`getKey()` Returns the selected key.

    Methods in javax.xml.crypto with parameters of type Key
    Modifier and Type | Method and Description
    --- | ---
    `static KeySelector` | KeySelector.`singletonKeySelector(Key key)` Returns a `KeySelector` that always selects the specified key, regardless of the `KeyInfo` passed to it.

  - ### Uses of Key in javax.xml.crypto.dsig.dom

    Constructors in javax.xml.crypto.dsig.dom with parameters of type Key
    Constructor and Description
    `DOMSignContext(Key signingKey, Node parent)` Creates a `DOMSignContext` with the specified signing key and parent node.
    `DOMSignContext(Key signingKey, Node parent, Node nextSibling)` Creates a `DOMSignContext` with the specified signing key, parent and next sibling nodes.
    `DOMValidateContext(Key validatingKey, Node node)` Creates a `DOMValidateContext` containing the specified key and node.

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