BASE64算法，MD5算法，SHA算法，HMAC算。 教程中包含上述几种算法的java实现方式。很详细。-BASE64 algorithm, MD5 algorithm, SHA algorithm, HMAC calculation. Tutorial contains the java implementation of several algorithms. Very detailed.

This book describes the Java Virtual Machine, the abstract computer on which all Java programs run. Through a combination of tutorial explanations, working examples, reference material, and applets that interactively illustrate the concepts presented