Java核心技术 卷Ⅱ高级特性

Java核心技术 卷Ⅱ高级特性(中文3500字,英文2300字)
当Java技术刚刚问世时，令人激动的并不是因为它是一个设计完美的编程语言，而是因为它能够安全地运行通过因特网传播的各种applet。很显然，只有当用户确信applet的代码不会破坏他的计算机时，用户才会接受在网上传播的可执行的applet。正因为如此，无论过去还是现在，安全都是设计人员和Java技术使用者所关心的一个重大问题。这就意味着，Java技术与其他的语言和系统有所不同，在那些语言和系统中安全是事后才想到要去实现的，或者仅仅是对破坏的一种应对措施，而对Java技术来说，安全机制是一个不可分割的组成部分。
Java技术提供了以下三种确保安全的机制：

Core Java™ Volume II–Advanced Features
When Java technology first appeared on the scene, the excitement was not about a well-crafted programming language but about the possibility of safely executing applets that are delivered over the Internet (see Volume I, Chapter 10 for more information about applets). Obviously, delivering executable applets is practical only when the recipients are sure that the code can't wreak havoc on their machines. For this reason, security was and is a major concern of both the designers and the users of Java technology. This means that unlike other languages and systems, where security was implemented as an afterthought or a reaction to break-ins, security mechanisms are an integral part of Java technology.