javax.crypto.spec
Class SecretKeySpec

java.lang.Object
  javax.crypto.spec.SecretKeySpec

All Implemented Interfaces:

Key, KeySpec, SecretKey, Serializable

public class SecretKeySpec

extends Object

implements KeySpec, SecretKey

This class specifies a secret key in a provider-independent fashion.

It can be used to construct a SecretKey from a byte array, without having to go through a (provider-based) SecretKeyFactory.

This class is only useful for raw secret keys that can be represented as a byte array and have no key parameters associated with them, e.g., DES or Triple DES keys.

Since:

1.4

See Also:

SecretKey, SecretKeyFactory, Serialized Form

Field Summary

Fields inherited from interface java.security.Key

serialVersionUID

Constructor Summary

SecretKeySpec(byte[] key, int offset, int len, String algorithm)
Constructs a secret key from the given byte array, using the first len bytes of key, starting at offset inclusive.

SecretKeySpec(byte[] key, String algorithm)
Constructs a secret key from the given byte array.

Method Summary

boolean	equals(Object obj)
String	getAlgorithm() Returns the name of the algorithm associated with this secret key.
byte[]	getEncoded() Returns the key material of this secret key.
String	getFormat() Returns the name of the encoding format for this secret key.
int	hashCode() Calculates a hash code value for the object.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SecretKeySpec

public SecretKeySpec(byte[] key,
                     String algorithm)

Constructs a secret key from the given byte array.

This constructor does not check if the given bytes indeed specify a secret key of the specified algorithm. For example, if the algorithm is DES, this constructor does not check if key is 8 bytes long, and also does not check for weak or semi-weak keys. In order for those checks to be performed, an algorithm-specific key specification class (in this case: DESKeySpec) should be used.

Parameters:

key - the key material of the secret key.

algorithm - the name of the secret-key algorithm to be associated with the given key material. See Appendix A in the Java Cryptography Extension API Specification and Refernce for information about standard algorithm names.

SecretKeySpec

public SecretKeySpec(byte[] key,
                     int offset,
                     int len,
                     String algorithm)

Constructs a secret key from the given byte array, using the first len bytes of key, starting at offset inclusive.

The bytes that constitute the secret key are those between key[offset] and key[offset+len-1] inclusive.

This constructor does not check if the given bytes indeed specify a secret key of the specified algorithm. For example, if the algorithm is DES, this constructor does not check if key is 8 bytes long, and also does not check for weak or semi-weak keys. In order for those checks to be performed, an algorithm-specific key specification class (in this case: DESKeySpec) must be used.

Parameters:

key - the key material of the secret key.

offset - the offset in key where the key material starts.

len - the length of the key material.

algorithm - the name of the secret-key algorithm to be associated with the given key material. See Appendix A in the Java Cryptography Extension API Specification and Reference for information about standard algorithm names.

Method Detail

getAlgorithm

public String getAlgorithm()

Returns the name of the algorithm associated with this secret key.

Specified by:

getAlgorithm in interface Key

Returns:

the secret key algorithm.

getFormat

public String getFormat()

Returns the name of the encoding format for this secret key.

Specified by:

getFormat in interface Key

Returns:

the string "RAW".

getEncoded

public byte[] getEncoded()

Returns the key material of this secret key.

Specified by:

getEncoded in interface Key

Returns:

the key material

hashCode

public int hashCode()

Calculates a hash code value for the object. Objects that are equal will also have the same hashcode.

equals

public boolean equals(Object obj)