| BadPaddingException | 
 This exception is thrown when a particular padding mechanism is
 expected for the input data but the data is not padded properly. 
 | 
| Cipher | 
 This class provides the functionality of a cryptographic cipher for
 encryption and decryption. 
 | 
| CipherSpi | 
 This class defines the Service Provider Interface (SPI)
 for the Cipher class. 
 | 
| ExemptionMechanism | 
 This class provides the functionality of an exemption mechanism, examples
 of which are key recovery, key weakening, and
 key escrow. 
 | 
| ExemptionMechanismException | 
 This is the generic ExemptionMechanism exception. 
 | 
| ExemptionMechanismSpi | 
 This class defines the Service Provider Interface (SPI)
 for the ExemptionMechanism class. 
 | 
| 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. 
 | 
| 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. 
 | 
| NoSuchPaddingException | 
 This exception is thrown when a particular padding mechanism is
 requested but is not available in the environment. 
 | 
| SealedObject | 
 This class enables a programmer to create an object and protect its
 confidentiality with a cryptographic algorithm. 
 | 
| SecretKey | 
 A secret (symmetric) key. 
 | 
| SecretKeyFactory | 
 This class represents a factory for secret keys. 
 | 
| SecretKeyFactorySpi | 
 This class defines the Service Provider Interface (SPI)
 for the SecretKeyFactory class. 
 | 
| ShortBufferException | 
 This exception is thrown when an output buffer provided by the user
 is too short to hold the operation result. 
 |