e193. printing security system trace messages.txt

这里面包含了一百多个JAVA源文件

By setting the system property java.security.debug to all, the security system will print details of security related calls. The value all prints all available debugging information. For finer control of what is printed, see: 
    http://java.sun.com/j2se/1.4/docs/guide/plugin/developer_guide/debugger.html#jsdp

Here's an example of setting the system property on the command line: 
    java -Djava.security.debug=all MyApp


Here's a sample of trace messages: 
    access: access allowed (java.io.FilePermission c:\file1 read)
    access: access allowed (java.io.FilePermission c:\file2 write)
    access: access denied (java.util.PropertyPermission user.home read)
    Exception in thread "main" java.security.AccessControlException: access denied (
    java.util.PropertyPermission user.home read)
            at java.security.AccessControlContext.checkPermission(AccessControlContext.java:270)
            at java.security.AccessController.checkPermission(AccessController.java:401)
            at java.lang.SecurityManager.checkPermission(SecurityManager.java:542)
            at java.lang.SecurityManager.checkPropertyAccess(SecurityManager.java:1291)
            at java.lang.System.getProperty(System.java:572)
            at MyApp.main(MyApp.java:50)