Considerations for the inherent methods and procedures

The inherent approach brings us some considerations for security issues. If your Java code emits a call to an intrinsic method, it is tantamount to passing control to the outside of the virtual machine "system." The inherent method has full access to the operating system!

Of course, if you write your own methods, that's exactly what we want. But this is unacceptable to the program-at least not tacitly. We don't want to see a piece of software downloaded from an Internet remote server that is free to manipulate the file system and other sensitive areas of the machine, unless it is specifically allowed to do so.

In order to prevent this from happening with j/direct,rni and COM integration, only the trusted (delegated) Java code has the authority to emit calls to the intrinsic method. According to the specific use of the program, the different conditions must be met before release. For example, a program that uses J/direct must have a digital signature, stating that it is fully trusted. While writing this book, not all of these security mechanisms have been implemented (for the Microsoft SDK for Java,beta version 2). So when the new version appears, be sure to keep an eye on its documentation.