Java's most striking claim is that it provides a secure programming environment. However, despite lots of discussion, few people understand precisely what Java's claims mean and how it backs up those claims. Java Security is an in-depth exploration aimed at developers, network administrators, and anyone who needs to work with or understand Java's security mechanisms. It discusses in detail what security does and doesn't mean, what Java's default security policies are, and how to create and implement your own policies. In doing so, Java Security provides detailed coverage of security managers, class loaders, the access controller, and much of the java.security package. It discusses message digests, certificates, and digital signatures, showing you how to use Java's facilities for signing classes or to implement your own signature facility. It shows you how to write a class loader that recognizes signed classes, verifies the signature, and cooperates with a security manager to grant additional privileges. It also discusses the problem of managing cryptographic keys and shows you how to implement your own key management systems. Java Security is an essential book for everyone using Java in real-world software. If you're deploying software written in Java, you need to know how to grant your classes the privileges they need, without granting privileges to untrusted classes. You need to know how to protect your systems against intrusion and corruption. Java provides the tools; this book shows you how to use them.