Java in a Nutshell, 5th Edition

Name

Package javax.crypto

Synopsis

The javax.crypto package defines classes and interfaces for various cryptographic operations. The central class is Cipher, which is used to encrypt and decrypt data. CipherInputStream and CipherOutputStream are utility classes that use a Cipher object to encrypt or decrypt streaming data. SealedObject is another important utility class that uses a Cipher object to encrypt an arbitrary serializable Java object.

The KeyGenerator class creates the SecretKey objects used by Cipher for encryption and decryption. SecretKeyFactory encodes and decodes SecretKey objects. The KeyAgreement class enables two or more parties to agree on a SecretKey in such a way that an eavesdropper cannot determine the key. The Mac class computes a message authentication code (MAC) that can ensure the integrity of a transmission between two parties who share a SecretKey. A MAC is akin to a digital signature, except that it is based on a secret key instead of a public/private key pair.

Like the java.security package, the javax.crypto package is provider-based, so that arbitrary cryptographic implementations may be plugged into any Java installation. Various classes in this package have names that end in Spi. These classes define a service-provider interface and must be implemented by each cryptographic provider that wishes to provide an implementation of a particular cryptographic service or algorithm.

This package was originally shipped as part of the Java Cryptography ...