Appendix D. The Secure Java Container

In this appendix, we'll outline a container that is capable of running Java programs securely. The term container is most often used to refer to a Java 2 Enterprise Edition (J2EE) application server; the application server provides an environment in which you run your programs. But containers need not be J2EE application servers: Java-enabled browsers are applet containers, the Java command line sets up a J2SE application container, and so on. A container is just a shell that runs other code.

In Java 2, when you execute the Java program, you're actually starting a container that is referred to as the launcher. The launcher is set up to run applications security within the Java 2 framework (assuming that you've specified the -Djava.security.manager option). In order to achieve something similar in Java 1.1, you have to write a container from scratch; the container is responsible for setting a security manager, using an appropriate class loader, and so on.