The Java Cryptography Extension
The standard Java Development Kit comes with a security framework called the Java Cryptography Architecture (JCA). The interesting thing about the JCA is that it doesn't provide you a way to do cryptography. Instead, it provides some useful utilities and cryptography-related items, such as digital signatures. If you want to encrypt or decrypt data, you must use the Java Cryptography Extension (JCE) or a third-party encryption library.
Technically, the JCE is a framework for encryption providing various software vendors with a standard way to make their encryption libraries available to Java developers. The JCE does come with a reference implementation that includes several common encryption algorithms, so you