Added in API level 1

javax.crypto

Provides the classes and interfaces for cryptographic operations. The cryptographic operations defined in this package include encryption, key generation and key agreement, and Message Authentication Code (MAC) generation.

Support for encryption includes symmetric, asymmetric, block, and stream ciphers. This package also supports secure streams and sealed objects.

Many of the classes provided in this package are provider-based. The class itself defines a programming interface to which applications may write. The implementations themselves may then be written by independent third-party vendors and plugged in seamlessly as needed. Therefore application developers may take advantage of any number of provider-based implementations without having to add or rewrite code.

Package Specification

For further documentation, please see:

Interfaces

SecretKey A secret (symmetric) key. 

Classes

Cipher This class provides the functionality of a cryptographic cipher for encryption and decryption. 
CipherInputStream A CipherInputStream is composed of an InputStream and a Cipher so that read() methods return data that are read in from the underlying InputStream but have been additionally processed by the Cipher. 
CipherOutputStream A CipherOutputStream is composed of an OutputStream and a Cipher so that write() methods first process the data before writing them out to the underlying OutputStream. 
CipherSpi This class defines the Service Provider Interface (SPI) for the Cipher class. 
EncryptedPrivateKeyInfo This class implements the EncryptedPrivateKeyInfo type as defined in PKCS #8. 
ExemptionMechanism This class provides the functionality of an exemption mechanism, examples of which are key recovery, key weakening, and key escrow. 
ExemptionMechanismSpi This class defines the Service Provider Interface (SPI) for the ExemptionMechanism class. 
KeyAgreement This class provides the functionality of a key agreement (or key exchange) protocol. 
KeyAgreementSpi This class defines the Service Provider Interface (SPI) for the KeyAgreement class. 
KeyGenerator This class provides the functionality of a secret (symmetric) key generator. 
KeyGeneratorSpi This class defines the Service Provider Interface (SPI) for the KeyGenerator class. 
Mac This class provides the functionality of a "Message Authentication Code" (MAC) algorithm. 
MacSpi This class defines the Service Provider Interface (SPI) for the Mac class. 
NullCipher The NullCipher class is a class that provides an "identity cipher" -- one that does not transform the plain text. 
SealedObject This class enables a programmer to create an object and protect its confidentiality with a cryptographic algorithm. 
SecretKeyFactory This class represents a factory for secret keys. 
SecretKeyFactorySpi This class defines the Service Provider Interface (SPI) for the SecretKeyFactory class. 

Exceptions

AEADBadTagException This exception is thrown when a Cipher operating in an AEAD mode (such as GCM/CCM) is unable to verify the supplied authentication tag. 
BadPaddingException This exception is thrown when a particular padding mechanism is expected for the input data but the data is not padded properly. 
ExemptionMechanismException This is the generic ExemptionMechanism exception. 
IllegalBlockSizeException This exception is thrown when the length of data provided to a block cipher is incorrect, i.e., does not match the block size of the cipher. 
NoSuchPaddingException This exception is thrown when a particular padding mechanism is requested but is not available in the environment. 
ShortBufferException This exception is thrown when an output buffer provided by the user is too short to hold the operation result.