课程：快速浏览控制应用程序

This lesson shows how to use a security manager to grant or deny access to system resources for applications. The lesson also shows how resource accesses, such as reading or writing a file, are not permitted for applications that are run with a security manager unless explicitly allowed by a permission entry in a policy file.

The steps for this lesson are:

1. 观察应用程序自由
2. 了解如何限制应用程序
3. Set Up the Policy File to Grant the Required Permissions
4. 查看策略文件效果