Sandra Baker

Hi,
I am using Tomcat Form authentication to have user login. Is there anyway I can add a link or button that user can logout whenever he/she intends to?
<% HttpSession ses = request.getSession(true);
if (ses != null){
ses.invalidate();
}
%>
Sorry, I am really new to jsp/servlet... thanks

Here is my lock and unlock.... please give me some feedback, I am kinda skeptical about two synchronized (myobj) in the lock...Thanks
//myObj stores the locked record numbers private static Set myObj = Collections.synchronizedSet(new HashSet()); public void lock(recordNum) throws RemoteException, IOException{ try{ synchronized(myObj){ while(myObj.contains(recordNum) == true){ //notifyAll, release the monitor of the object for others //wait } } }catch (InterruptedException ie){System.out.println(ie);} } synchronized(myObj){ //add record //notifyAll } public void unlock(recordNum) throws RemoteException{ synchronized(myObj){ //remove record //notifyAll } }
[ October 10, 2002: Message edited by: Sandra Baker ]

(Edited the original post.....)
I used this data structure to store my locked record number, do I need to synchronize the object?
private static SortedSet lockedRec = Collections.synchronizedSortedSet(new TreeSet());
Here is how it works:
Clients need to check if the record number is currently in the lockedRec, if not, can lock the record. If yes, use while loop to try certain amount of times ( i set it to be 100 sec), after this amount of time, there may be something wrong with the client who's currently locking this record, then, explicitly unlock the record by the server.
[ October 09, 2002: Message edited by: Sandra Baker ]

Is this the right book for preparing this exam? Please advise... thanks

Pete,
Thanks for reply. Are you suggesting that db.db should be put in the executable jars? I thought db.db location should be as flexible as possible?! Say, if FBN comany expands rapidly, they decide to have a database server, and would like to move the db.db to the new location..... Aren't we restricting ourselves by only allowing db.db to be in certain location?
Currently, I am having client-side and server-side command-lines take database location (either relative path or absolute path) as one of the parameters....
Thanks

Hi,
I was wondering if it is possible that the Sun Accessor deducted a lot points just because they did not understand what and why you are doing things these ways? Although, I tried in design choice doc to explain as much as possible, I still think they might not really know why I make those design choices?
Any suggestions? Thanks

Hi Sam,
Glad to hear that you got the feedback.... see, the problem is "none of above" all of us have guessed....
Best luck to you.
Sandra

I think the reason there are some many confusions and panic is that Sun thought they have pretty clear instructions but people actually understand things in different ways..... I don't agree what they simply throw a FAIL to candidate without a single comment or feedback.
I think we deserve at least 3-5 sentence explaination. Remember, we spend $400 for the exam, and countless hour of hardworking....
Maybe the accessor just received a pink slip, and tried to do something destuctive.... . Hey, you never know....trust me, human behavior is unpredictable......Okay. What I am trying to say is email them ask for their comments. Otherwise, you will spend a lot of time guessing. You have done enough work already..... its their turn.
[ September 24, 2002: Message edited by: Sandra Baker ]

Hi Sam,
Could you please tell me when you uploaded and took the written exam? I saw its 9/21.... how come you got the result so soon....
I am very worried...because it seems the graders around this time is not very "friendly".....
Thanks

Hi, but I did not see any requirement stating that we should follow the "java code convention". Also, some codes are really easier to read if leave them to be one line, not wrapping them.
I am extremly frustrated now. I have submitted my assignment, and I keep noticing something I missed...... Is Sun really asking for those patterns, models, and styles in the exam? They are really not in my requirement document.
Too late......
Hope miracle will happen, that's all I can do now.
Wish all of you, who is still in the process, the best luck.
[ September 24, 2002: Message edited by: Sandra Baker ]

Hi, Chris
It is my personal experience. Try small programs whenever you are not sure about what a code segment will do. One or a few lines of code really help a lot.......
Good luck
Sandra

Hi Michael,
Thanks... I will keep trying to look into this....I was not expecting to experience "this pain" in this process

Hi Michael & Ravi,
Thanks very much for the information, and that's exactly what I was worried about.
I found out a way not need to specify codebase, however, it does not make much sense to me...
Here is what I tried, included all of the following files under e:\Test\
- server.jar (executalbe jar, includes all classes and folders I mentioned in my previous post)
- server folder (stubs are here)
- interface folder
I guess, this time, JVM directly go to server folder to find my stubs, not the jar executable file.
Does this sound reasonalbe to you? I feel somewhat redundant for having two copies of stubs under that same directory......
I did not touch any CLASSPATH....., is there a way to cleanup all CLASSPATH, becuase i want to make sure that there is no CLASSPATH that interferes with my testing.....
Thanks in advance....
[ September 20, 2002: Message edited by: Sandra Baker ]

Hi, janapareddy
I had the same problem as yours, and now I think I solved it, just for your reference.
I made an executalbe server.jar, and put it under e:\Test\. The jar includes following folders:
- server: includes all server classes and stubs (my server main class is in this folder too)
- interface: includes all interfaces
- db: includes all Data related classes
Then, I specified codebase property like:
-Djava.rmi.server.codebase=file:/e:\Test\server.jar
Then, JVM will be able to find your stub classes in your executable jar......
Try this.... hope it will work for you.

Hi, I have the exact same problem. After searching for a long time, only one way worked for me....put stub classes in HTTP server.
However, as Michael said, it would not be a good idea ask the grader put the stubs in HTTP or FTP server... what if they don't have it on their testing machine..
I am trying to use codebase.....where should the stubs locate? Should I set CLASSPATH on the server machine?
Right now, I have "server.jar", which is an executable jar and includes all my server-side classes and stubs. "client.jar" is an executable jar, which includes all client-side classes. I tried this command line, the error is that client could not find my stub..... Maybe something wrong with my codebase property, could somebody please take a look?
Start Server:
E:\RMI>start rmiregistry
E:\RMI>java -Djava.security.policy=file:/e:\RMI\security.policy -jar server.jar
Start Client:
E:\RMI>java -Djava.rmi.server.codebase=file:/e:\RMI\server.jar -Djava.security.policy=file:/e:\RMI\security.policy -jar client.jar 198.192.0.40 1099 db.db
Then, I got error:
java.rmi.UnmarshalException: error unmarshalling return; nested exception is:
java.lang.ClassNotFoundException: server.ConnectionFactory_Stub
[ September 19, 2002: Message edited by: Sandra Baker ]