Advanced Programming for the Java 2 Platform Quiz

1. If classes, libraries, or Windows registry entries from previous installations remain on your system after an upgrade, there is a chance the new software mix might cause program problems.

2. What does the verbose option to the java interpreter command do?

3. The -Ddebug option to the java interpreter command lets you turn debug mode on from the command line. What are the advantages of doing this?

4. Compiling with the debug flag adds debug information to the class. How can you reduce the size of these classes?

5. Is it possible to debug an applet running in applet viewer?

6. What is an agent password and when is it used?

7. Servlets cannot be debugged with jdb.

8. You can use an AWTEventListener to monitor the AWT events in a system event queue. This listener takes an event mask built from an OR operation of the AWTEvents you want to monitor. How can you obtain a simple list of AWT events?

9. A stack trace is a snapshot of the threads and monitors in a Java virtual machine. When you see a stack trace, you will see different threads in many different states. What does the MW thread state mean?

10. What can network-based applications use to save on the time and overhead involved in opening and closing network connections?

11. Cached database connections cannot be reused.

12. The Java 2 release of the Java virtual machine automatically inlines simple methods at run time. How does method inlining improve performance?

13. Performance analysis is looking at program execution to pinpoint where bottlenecks or other performance problems such as memory leaks might occur. Which of the following tools let you analyze Java virtual machine heap profile reports?

14. What command lets you generate a text profile report?

15. The Java virtual machine depends on many operating systems libraries for functionality, such as disk access or networking. However, what occurs in these libraries is of no consequence to performance.

16. Keeping objects in cached memory for rapid access is a common technique for improving performance. What is a simple algorithm to constrain cache size to limit the amount of memory dedicated to cached objects?

17. When do you need to install Java Plug-In?

18. A security policy file grants access permissions to an applet so the applet can access local system resources. There are three kinds of security policy files: system, user, and program. Where is the user policy file located?

19. By default the Java 2 platform software provides a security manager that disallows all access to local system resources.

20. The Java 2 platform security manager restricts all applets to a sandbox-like environment. How do you force an application to run under the Java 2 platform security manager and provide a security policy file with only limited permissions?