J2ee session variables

hi, i have been trying to use session variables in my app. I
have enabled the session variables in the cf admin, and in the
application.cfc.
However when i try to run my app it says session is invalid.
The session doesnt even start. I get this error everytime unless i
turn off the j2ee session variables. I have checked both the j2ee
and and session timeouts. the session is set at 30 and the j2ee
timeout is set to 66.
I have read the coldfiusion documentationand feel that i
would like to use j2ee session.
i am using this in a single site andon the developers
edition. Cany anyone help me understand why this error is occuring
and how i can get around it
i would appreciate any help
thanks

I would first make sure you have the latest
patches/update/hot fixes.
The 'session is invalid' is/was a known problem.
http://www.adobe.com/cfusion/knowledgebase/index.cfm?id=tn_17883
http://www.adobe.com/cfusion/knowledgebase/index.cfm?id=aae43964
Perhaps you simply need to apply the appropriate update.
Good luck!

Similar Messages

J2EE session variables & Non Random Session IDs

Our server keeps failing our PCI compliance test due to the Session ID's being non random.
Description: Web Server Uses Non Random Session IDs Synopsis: The remote web server generates predictable session IDs. Impact: The remote web server generates a session ID for each connection. A session ID is typically used to keep track of the actions of a user while he visits a web site. The remote server generates non-random session IDs. An attacker might use this flaw to guess the session IDs of other users and therefore steal their session. See also : http://pdos.csail.mit.edu/cookies/seq_sessionid.html Data Received: Sending several requests gives us the following session IDs : CFID=896744 CFID=896745 CFID=896746 CFID=896747 CFID=896748 Resolution: Configure the remote site and CGIs so as to use random session IDs. Risk Factor: Medium/ CVSS2 Base Score: 6.4 AV:N/AC:L/Au:N/C:P/I:P/A:N
We are using J2EE session variables which I though was the more secure option. Is there something else you have to do to guarentee that the Session ID's are non random or is this the Compliance test picking up on a false positive?
P.S. It's a recent migration to CF10, don't know if that has anything to do with it.

Personally, I use the client scope instead of the session scope so that I don't have to worry about sticky sessions. That has always worked out nicely for me.
I read that article you referenced, and it's got some interesting stuff. In particular, I have seen the client scope database tables not purge as they're supposed to. And the stuff about preparing, executing, and then unpreparing SQL statements on each request is alarming, if true.
However, I have to say that I have never, ever, ever, ever had performance issues due to client variables. Not once. Whatever performance hit my application may incur from using client variables has, to this point, been completely dwarfed by the performance of the application itself. And, c'mon, the stuff about being lazy because you don't want to spend precious engineering time worrying about something like session management (which is never going to add value to your product) rather than coding something actually useful to your end users...that seems overly harsh to me.
I completely agree that storing client vars in the Windows Registry is bananas, as is the defualt 90 day purge limit (though as of CF 9.0.whatever, the default is 1 day, 7 hours, so clearly they've made some changes since this article was written). But I'm loathe to throw away client-based management.
I think, getting back to the issue at hand, that this may be a false positive. CFID is sequential, but CFTOKEN is not; that should really be the end of the story. I'll see if McAfee will listen. (-;

CFLOGIN not maintaining cfauthrization session variable

I have a simple CF web site where all of the .cfm is in the
same directory. I can not use client cookies as the people I am
writing this for have cookies turned off in IE, therefore I am
using J2EE session variables and CFLOGIN in an application.cfm file
(code attached) for authentication. Everything works correctly
during login and I can see the encrypted username/password as the
cfauthorization session variable....
Session Variables:
cfauthorization=Y3BkYWRtaW46cmVwb3J0ODQzOmNwZA==
sessionid=c23059df643c42544069
urltoken=CFID=783&CFTOKEN=91556252&jsessionid=c23059df643c42544069
Once I try to browse to another cfm page on the site, I get
booted back to the index.cfm login page. After some digging I
figure out that the cfauthorization variable was blank after I
click on the link, which as I understand it indicates that I am not
logged in and the
<cfif not IsDefined("cflogin")>
<cfinclude template="index.cfm">
<cfabort>
code in the application.cfm sends me back to the login page.
I have confirmed that using valid credentials causes <cfif
cpdauth.recordcount GT "0"> to return true.
Any idea as to why my session authorization is not being
maintained between pages? Or if I am completely off base as to the
reason this is happening.....and if so, what am I doing wrong.
Thanks
Greg

Your login code seems to be fine. You yourself are already
aware that you have to have a way to pass-the-baton between
requests, to maintain a session.
The usual way Coldfusion maintains sessions is to send CFID
and CFTOKEN cookies to the client browser. That happens
automatically under the hood, assuming you haven't switched
setClientCookies off.
For session management by means of cookies, I would use a
cfapplication tag like
<cfapplication name = "cpd"
applicationTimeout = "#createTimespan(1,0,0,0)#"
sessionManagement = "yes"
clientManagement = "yes"
sessionTimeout = "#createTimeSpan(0,0,20,0)#"
setClientCookies = "true"
scriptprotect="all"
loginstorage="Session">
However, all of that assumes that the client browser accepts
cookies. Where it doesn't, the usual way to maintain sessions is to
pass CFID and CFTOKEN values in the URL of every request. In fact,
the function that Bluetone suggests,
URLSessionFormat,
makes the process efficient. It instructs Coldfusion to append CFID
and CFTOKEN to the URL only when the client doesn't accept cookies.
Which means Coldfusion would still be using cookies wherever
possible. Some examples
<a href="#URLSessionFormat('orders.cfm')#">My
orders</a>
<cfform method="Post"
action="#URLSessionFormat("MyActionPage.cfm")#">
</cfform>
<cflocation url = "products.cfm" addToken = "yes">

CFID and CFTOKEN still set when using J2EE sessions

I'm using CF10 and "Use J2EE session variables" is selected in the CF admin.
When I visit an application, I get the JSESSIONID cookie, but I also get the CFID and CFTOKEN persistent cookies. The app I'm working with is older and uses Application.cfm instead of Application.cfc, but the clientmanagement and setclientcookies application attributes are set to false.
I'm not sure why CFID and CFTOKEN are still set. Are they set regardless of the client and session management settings?

cherdt
There are ways to force the CF create cookies SESSION simply change the cfcookie to be a session cookie and tag you find these two links:
http://www.bennadel.com/blog/1131-ask-ben-ending-coldfusion-session-when-user-closes-brows er.htm
http://www.johnwbartlett.com/cf_tipsntricks/index.cfm?TopicID=75
BKBK
I agree with his statement and is so even though the documentation says.

Urgent help required...for replacing JSP session variables

I am trying to enhance the performance of a j2ee based webapp which use session variables to store the data...
Is there any alternative for session variables..The project is based on j2ee-Struts frame work..But the amount of code maintainance should be minimum ....so i can't create beanforms for all these data...
Is there any XML based methods available...??

ok... thanks... i created a fla file and inthe action script
pasted the following code
var nc:NetConnection = new NetConnection();
nc.connect("rtmp://flash.ispstream.com/ondemand/unikron/my_video_dj/");
var ns:NetStream = new NetStream(nc);
contentMain.myVideo.attachVideo(ns);
ns.setBufferTime(5);
ns.play("dvd_r");
nothing is working if i tried to load... can u help me out

Passing session variables

Hello....
I have created a simple form that populates with data from a SQL db. I'm connecting fine, but only pulling data from the initial record. I'm trying to have users click "print form" from an .asp page that passes a session variable, then opening my livecycle form with their specific data. Can't get a SQL Query "select" statement to query to that single file.
Is it possible to query the data on my form from a session variable via asp vbscript?
Thanks

Hi, Simson:
I just bumped onto this post of yours. After reading it several times, I could not understand exactly what you meant still. Maybe you can use a few more lines or an example to show what you want.
By they way, as far as I can remember, it is against j2ee spec to share session between web applications, if that is what you are driving at.

To pass new session variable value to stored proc before running a report.

Hi,
Below is summary of the report requirement -
Database level design
1. Created a view and a global temporary table (GTT)
2. Created an Oracle package procedure to accept from and to business dates on basis of which it will fetch, process and populate the GTT.
Repository level design
1. Created a business model containing the view and the GTT (mentioned above)
2. Created two SESSION variables "from_dt" and "to_dt" to be initialized by their respective init blocks. Each of the variable is initialized with a DATE column value (of type DATETIME) from a database lookup table. I have also set the option "Enable that variable to be set by any user" for both variables.
Query for these variables :
from_dt = select from_date from <table>
to_dt = select add_months(from_date,12) from <table>
Presentation level design
1. Using a text box, i display the default/initialized values of these variables like this -
Current business date:@{biServer.variables['NQ_SESSION.from_dt']} Future business dt:@{biServer.variables['NQ_SESSION.to_dt']}
Dates get displayed in YYYY-MM-DD 00:00:00 format
The text msg displays these default dates and allows the user to specift different date range for which i create prompts as shown below.
2. Using any random two columns of date type from the business model, i create two date dashboard prompts with labels "From Dt" and "To Dt".
i select Calender Controls for both; setting Default To = Report Defaults.
The Set Variable is set to Presentation variables - such that pv_from_dt maps to "From Dt" and pv_to_dt maps to "To Dt".
3. i create the report using the business model created above. In the report "Advanced Tab" => "Prefix" field i specify the following -
SET VARIABLE from_dt='@{pv_from_dt}',to_dt='@{pv_to_dt}';
Note : The logic here is to display the default dates and allow user to specify different date values which will be stored in presentation variables.
If the user does specify different "from dt" and "to dt" values, then using the presentation variables, i want to "write" back these new values to the corresponding session variables mentioned above.
If the user does not specify different date range, then the default/initialized dates must be considered.
I also display the default and new date values in the report title.
Back to Repository level design
To execute the stored procedure that will load the GTT before running the report I need to pass two date parameters to the stored procedure on basis of which it will fetch data, process and populate the GTT.
In the Connection Pool --> Connection Script Tab --> Execute before query, I wrote the below query using the repository variables FROM_DT and TO_DT to execute the procedure -
DECLARE
v_from_dt date;
v_to_dt date;
BEGIN
v_from_dt := VALUEOF(From_Dt);
v_to_dt := VALUEOF(To_Dt);
package_name1.package_body(v_from_dt,v_to_dt);
END;
Now when i try to run the report i get the following error :
[nQSError: 10058] A general error has occurred. [nQSError: 23006] The session variable, NQ_SESSION.to_dt, has no value definition. (HY000)..
Need help on this.
Is it possible to "write back" a new value to a session variable ?
Any other alternatives.
Thanks
Nusrat
Edited by: user10309945 on Jan 24, 2011 10:08 PM

Sandeep, I found a several topics where users describe saving values in DB through stored procedure or function. For example, [How to store OBIEE presentation level variable values in DB |http://forums.oracle.com/forums/thread.jspa?threadID=892006] I tried it and get an error
*10058. [NQODBC] [SQL_STATE: HY000] [nQSError: 10058] A general error has occurred. [nQSError: 17001] Oracle Error code: 14551, message: ORA-14551: cannot perform a DML operation inside a query ORA-06512*
It's not a BI error. This error are generated by Oracle DB. If I write next:
SELECT MyPLSQLFunction(p1,p2) FROM DUAL
I get the same error.
Oracle doesn't allow DML operations in SELECT.
Did you relalize this feature yourself? Where did I mistake?

Session variable size limitation (LV Webservices)

Hi community,
I read couple dozen email addresses from an XML and trying to write them into a session variable. The email addresses are comma separated and have a total string length of about 1100 characters. When I try to write it into a session variable LabVIEW drops an error message (-67158).
It is very clearly related to the size of the string as if use lets say only 200 characters I dont receive the error message.
How can I get rid of this limitation?
Thanks!

I am writing a general purpose webpage where I need email notifications. I have the workaround ready (before I send out the emails I dont read the emails from a session, but using the userID stored in the session to read the email from the xml). But generally having this limitation is annoying and unnecessary as normally you easily can store 100kB in one session. (probably even more, but that was the max I have ever did)

Trying to move a list of form variables to session variables of the same name

I am trying to move a list of form variables to session variables of the same name and I am having a lot of trouble.
I have never had to post of this forum with a language question in all the 10 years I have been using ColdFusion. I was a qa Engineer @ Allaire/Macromedia back when it was going from one to the other. I have a pretty good grasp of the language.
I have software that runs off a list. The fieldnames are variable and stored off in an array. It's survey software that runs off a "meta file". In this example; I have the number of fields in the survey set to 12 in the "metafile". I have each field declared in that file in array Session.SurveyField[1] and the above loop works fine. I include this "metafile" at the start of the process.
I cfloop around a struct and it works wherever I have needed to use it; such as here - writing to the database for example;
<CFQUERY NAME="InsertRec" DATASOURCE="Survey">
INSERT into #variables.SurveyTableName#
(EntryTime
<cfloop from="1" to="#Session.NumberOfSurveyFields#" index="arrayindex">
,#Session.SurveyField[arrayindex]#
</cfloop>

   VALUES
    ('#EntryTime#'
<cfloop from="1" to="#Session.NumberOfSurveyFields#" index="arrayindex">
<cfset thisname = "Session." & Session.SurveyField[arrayindex]>
,'#evaluate(variables.thisname)#'
</cfloop>

</CFQUERY>
NOW HERE'S THE PROBLEM: I am running into trouble when trying to move the form variables to session variables of the same name. It is the only part of the software that I still need the datanames hard coded and that is a roadblock for me.
<cfloop from="1" to="#Session.NumberOfSurveyFields#" index="arrayindex">
<cfset thissessionfield = "Session." & Session.SurveyField[arrayindex]>
<cfset thisformfield = "Form." & Session.SurveyField[arrayindex]>
<cfset #thissessionfield# = #evaluate(thisformfield)#>
</cfloop>
I have tried it with or without the "evaluate"; same result. It doesn't give an error; it just ignores them (session variables look as such in the next page in the chain)
q01_name=
q02_acadtechorna=
q03_water=
q04_firstaid=
q05_cpr=
q06_lifeguard=
q07_aed=
q08_projadv=
q09_color=
q10_santaclaus=
q11_supervisor=
q12_supervisoropinion=
Note: they exist because I CFPARAM them in a loop like the above at the start of the procedure) - and this works just fine!
<cflock scope="Session" type="EXCLUSIVE" timeout="30">
<cfloop from="1" to="#Session.NumberOfSurveyFields#" index="arrayindex">
<cfset dataname = "Session." & Session.SurveyField[arrayindex]>
<cfparam name="#variables.dataname#" default="">
</cfloop>
</cflock>
I EVEN tried exploiting the Form.Fieldnames list using CFLoop over the list and the same sort of logic within and it still gives me nothing....
Here's the FORM.FIELDNAMES value
"Q01_NAME,Q02_ACADTECHORNA,Q03_WATER,Q04_FIRSTAID,Q05_CPR,Q06_LIFEGUARD,Q07_AED,Q08_PROJAD V,Q09_COLOR,
Q10_SANTACLAUS,Q11_SUPERVISOR,Q12_SUPERVISOROPINION"
Here's the logic; SAME RESULT - The session variables don't get set.
<cfoutput>
<cfloop list="#Form.FieldNames#" index="thisfield">

<cfscript>
thisSESSIONfield = "Session." & thisfield;
thisFORMfield = "Form." & thisfield;
#thisSESSIONfield# = #thisFORMfield#;
</cfscript>
</cfloop>
</cfoutput>
The CFPARAM in a loop with variable output name works just fine; so does the post (which I included above) as does the SQL Create, Param Form Variables, Param Session Variables, etc.
THIS even works for moving BLANK to each session variable, to zero them all out at the end of the process;
<cflock scope="Session" type="EXCLUSIVE" timeout="30">
<cfloop from="1" to="#Session.NumberOfSurveyFields#" index="arrayindex">
<cfset thislocalfield = Session.SurveyField[arrayindex]>
<cfscript>
thissessionfield = "Session." & thislocalfield;
</cfscript>
<cfset #thissessionfield# = "">
</cfloop>
</cflock>
Expanding on that code, you would think this would work, but it doesn't;
<cfloop from="1" to="#Session.NumberOfSurveyFields#" index="arrayindex">
<cfset thislocalfield = Session.SurveyField[arrayindex]>
<cfscript>
thissessionfield = "Session." & thislocalfield;
thisformfield = "Form." & thislocalfield;
</cfscript>


<cfoutput>
<cfset #thissessionfield# = "#evaluate(thisformfield)#">
</cfoutput>
</cfloop>
And see that debug code in the middle? To add insult to injury... When I uncomment that it shows me this. So it certainly looks like this should work....
Session.q01_name = "Me"
Session.q02_AcadTechORNA = "N/A"
Session.q03_Water = "Yes (certificate expired)"
Session.q04_FirstAid = "Yes (certificate is current)"
Session.q05_CPR = "No"
Session.q06_LifeGuard = "Yes (certificate expired)"
Session.q07_AED = "Yes (certificate expired)"
Session.q08_ProjAdv = "Yes (certificate expired)"
Session.q09_Color = "Gray"
Session.q10_SantaClaus = "Yes"
Session.q11_Supervisor = "Da Boss"
Session.q12_SupervisorOpinion = "Not a bad thing"
There must be some simpler way to do this. This way won't work against all odds even though it seems so much like it should.
So I end up having to hardcode it; still looking for an automated way to set these #@%$*@!## session variables over the list from the form variables of the same @#@!$#%$%# name. Do I sound frustrated???
No matter what I do, if I don't HARDCODE like this;
<cfset Session.q01_name = Form.q01_name>
<cfset Session.q02_AcadTechORNA = Form.q02_AcadTechORNA>
<cfset Session.q03_Water = Form.q03_Water>
<cfset Session.q04_FirstAid = Form.q04_FirstAid>
<cfset Session.q05_CPR = Form.q05_CPR>
<cfset Session.q06_LifeGuard = Form.q06_LifeGuard>
<cfset Session.q07_AED = Form.q07_AED>
<cfset Session.q08_ProjAdv = Form.q08_ProjAdv>
<cfset Session.q09_Color = Form.q09_Color>
<cfset Session.q10_SantaClaus = Form.q10_SantaClaus>
<cfset Session.q11_Supervisor = Form.q11_Supervisor>
<cfset Session.q12_SupervisorOpinion = Form.q12_SupervisorOpinion>
I always get this from my next page because the session variables are empty;
You must answer question 1.
You must answer question 2.
You must answer question 3.
You must answer question 4.
You must answer question 5.
You must answer question 6.
You must answer question 7.
You must answer question 8.
You must answer question 9.
You must answer question 10.
I tried duplicate as well, but I can not get the above to work...
Can anyone help me do this thing that one would think is simple????

I think if you use structure array syntax you should get the results you want.
<cfloop from="1" to="#Session.NumberOfSurveyFields#" index="arrayindex">
      <cfset session[Session.SurveyField[arrayindex]] = Form[Session.SurveyField[arrayindex]]>
</cfloop>
Or probably even easier.
<cfset session = duplicate(form)>

Can we use session variables in BI publisher's Data Model SQL Query?

Hi Experts,
We need to implement Data level security in BI Publisher 11g.
In OBIEE we do so by using session variables, so just wanted to ask if we can use the same session variables in BI Publisher as well
ie can we include the where clause in the Data Models SQL Query like
Where ORG_ID = @{biServer.variables['NQ_SESSION.INV_ORG']}
Let me know your views on this.
PS: We are implementing EBS r12 security in BI Publisher.
Thanks

Read this -> OBIEE 11g: Error: "[nQSError: 23006] The session variable, NQ_SESSION.LAN_INT, has no value definition." when Creating a SQL Query using the session variable NQ_SESSION.LAN_INT in BI Publisher [ID 1511676.1]
Follow the ER - BUG:13607750 - NEED TO BE ABLE TO SET A SESSION VARIABLE IN OBIEE AND USE IT IN BI PUBLISHER
HTH,
SVS

Compare data record to session variable

I am completely stumped. It should be easy.
I am trying to compare a field from a database to a sesssion variable on a JSP page and even though the fields print out the same when I call them in JSP, my "If" statement never gets activated.
Here's the last version of the code I tried:
String usernamev = UserSession.getValue("username").toString();
String custname = RS.getString("ORCUST");
if (usernamev.equals(custname))
userrole="Customer ";
I've also tried this:
String usernamev = UserSession.getValue("username").toString();
String custname = RS.getString("ORCUST").toString;
if (usernamev.equals(custname))
userrole="Customer ";
And I've also tried this:
if (RS.getString("ORCUST").equals(usernamev))
userrole= "Customer ";
And This:
And I've also tried this:
if (usernamev.equals(RS.getString("ORCUST")))
userrole= "Customer ";
When RILLI is the field I'm trying to compare this works:
if (usernamev.equals("RILLI"))
userrole= "Customer ";
Somehow my data type must be wrong but I can't figure out why. When I print out
<%=usernamev%>
and <%=RS.getString("ORCUST")%>
they show on my webpage as RILLI. I can also assign a constant value to userrole without a problem.
What the heck am I doing wrong?

I think limeybrit was on the right track and I hadn't trimmed because I got a no trim method error before because I hadn't converted session variable to a string.
When I used this:
String usernamev = UserSession.getValue("username").toString();
usernamev = usernamev.trim();
String custname = RS.getString("ORCUST").trim();
I think its working now. Thanks for help all.

Session variable getting reset when leaving dashboard

I have created a session variable with the 'Enable any user to set the value' option. I'm using the session variable as the default for a dashboard prompt. I'm able to set the variable with that dasboard prompt, and I can confirm that it is indeed getting set properly. So the interaction of the variable and the prompt seems to be in order.
After I make a selection from the dashboard prompt, as long as I stay in the dashboard, the session variable stays set to my selection. I can move from page to page and everything is fine. The selection stays put as I have set it. However, the moment I leave the dashboard, the session variable is reinitialized back to its default value as specified by the SQL in its initialization block. I can go from dashboard to catalog and back to dashboard - boom, it's back to the default. My selection has been replaced. ???
And here's an odd thing: I can look in the query log and see the initialization block code getting run when I log in. So far, so good. I can run the dashboard, make a prompt selection, and see the query log updated just fine. Still OK. BUT... when I switch from dashboard to catalog and back to dashboard, the value of the session variable is reset (I see the default month in my analysis and as the prompt default upon redisplay of the dashboard page), but there's no indication in the query log that the initialization block SQL ran again. The last SQL in the query log still shows my "selected" value in the SQL. The dashboard page is showing the "default", while the last entry in the query log shows the "selected".
Can anyone else confirm this odd behavior? And is there a reason that a session variable should not retain its value throughout the session? I've always viewed session variables as little buckets of single-cell data whose contents are consistent and static for the duration of a session, unless manually changed by a dashboard prompt. If the behavior that I'm seeing is both replicatable and expected, it would appear that my understanding is flawed.
Running 11.1.1.7.0 on Windows Server 2008. Same behavior is occurring in both Firefox 21 and IE 9.

Thank you for your answer MK,
I try to write a SQL in my prompt but not work for me:
-In default selection I choose SQL Results and I type: Year(Current_date) and save my prompt and I don't see any value in my dashboardpage, if I click in prompt I can see all members of my year dimension but by default is empty.
I modify the other solution: I have 1hour refresh time and I change for 1 minute, but doesn't work.
the default initializer is in RPD (variable year that belongs to BI_Year Block) and I have written 2009.

Passing attribute value in session variable

Hi All
I need to store one field value from my SIM form as a session variable and pass them to the next page along with my session, using some jscript stuff or else. Does this make sense?
If it is possible or anyone have any prior experience please reply.
Thanks in advance

We have tested a code-snippet that 'gets' attribute-values from the session:
<invoke name='getAttribute'>
    <invoke name='getHttpSession'>
        <ref>:display.state</ref>
    </invoke>
    <s>attribute_name</s>
</invoke>You can try 'setAttribute' in the similar way.
Thanks,
Adi

Javacard and session variables

Hello,
I'm trying to find a reasonable Javacard technique to handle "session variables" that must be kept between successive APDUs, but must be re-initialized on each card reset (and/or each time the application is selected); e.g. currently selected file, currently selected record, current session key, has the user PIN been verified...
Such variables are best held in RAM, since changing permanent (EEPROM or Flash) variables is so slow (and in the long run limiting the operational life of the card).
Examples in the Java Card Kit 2.2.2 (e.g. JavaPurseCrypto.java) manipulate session variables in the following way:
1) The programmers group session variables of basic type (Short, Byte, Boolean) according to type, and map each such variable at an explicit index of a vector (one per basic type used as session variable).
2) At install() time, each such vector, and each vector session variable, is explicitly allocated as a transient object, and this object is stored in a field of the application (in permanent memory), where it remains across resets.
3) Each use of a session variable of basic type is explicitly translated by the programmer into using the appropriately numbered element of the appropriate vector.
4) Vector session variables require no further syntactic juggling, but eat up an object descriptor worth of permanent data memory (EEPROM or Flash), and a function call + object affectation worth of applet-storage memory (EEPROM, Flash or ROM).
The preparatory phase goes:
public class MyApp extends Applet {
// transientShorts array indices
    final static byte      TN_IX = 0;
    final static byte      NEW_BALANCE_IX=(byte)TN_IX+1;
    final static byte      CURRENT_BALANCE_IX=(byte)NEW_BALANCE_IX+1;
    final static byte      AMOUNT_IX=(byte)CURRENT_BALANCE_IX+1;
    final static byte   TRANSACTION_TYPE_IX=(byte)AMOUNT_IX+1;
    final static byte     SELECTED_FILE_IX=(byte)TRANSACTION_TYPE_IX+1;
    final static byte   NUM_TRANSIENT_SHORTS=(byte)SELECTED_FILE_IX+1;
// transientBools array indices
    final static byte      TRANSACTION_INITIALIZED=0;
    final static byte      UPDATE_INITIALIZED=(byte)TRANSACTION_INITIALIZED+1;
    final static byte   NUM_TRANSIENT_BOOLS=(byte)UPDATE_INITIALIZED+1;
// remanent variables holding reference for transient variables
    private short[]     transientShorts;
    private boolean[]   transientBools;
    private byte[]      CAD_ID_array;
    private byte[]      byteArray8; // Signature work array
// install method
    public static void install( byte[] bArray, short bOffset, byte bLength ) {
         //Create transient objects.
        transientShorts = JCSystem.makeTransientShortArray( NUM_TRANSIENT_SHORTS,
            JCSystem.CLEAR_ON_DESELECT);
        transientBools = JCSystem.makeTransientBooleanArray( NUM_TRANSIENT_BOOLS,
            JCSystem.CLEAR_ON_DESELECT);
        CAD_ID_array = JCSystem.makeTransientByteArray( (short)4,
            JCSystem.CLEAR_ON_DESELECT);
        byteArray8 = JCSystem.makeTransientByteArray( (short)8,
            JCSystem.CLEAR_ON_DESELECT);
(..)and when it's time for usage, things go:
    if (transientShorts[SELECTED_FILE_IX] == (short)0)
        transientShorts[SELECTED_FILE_IX] == fid;
    transientBools[UPDATE_INITIALIZED] =
        sig.verify(MAC_buffer, (short)0, (short)10,
            byteArray8, START, SIGNATURE_LENGTH);I find this
a) Verbose and complex.
b) Error-prone: there is nothing to prevent the accidental use of transientShorts[UPDATE_INITIALIZED].
c) Wastefull of memory: each use of a basic-type state variable wastes some code; each vector state variable wastes an object-descriptor worth of permanent data memory, and code for its allocation.
d) Slow at runtime: each use of a "session variable", especially of a basic type, goes thru method invocation(s) which end up painfully slow (at least on some cards), to the point that for repeated uses, one often attain a nice speedup by caching a session variable, and/or transientShorts and the like, into local variables.
As an aside, I don't get if the true allocation of RAM occurs at install time (implying non-selected applications eat up RAM), or at application selection (implying hidden extra overhead).
I dream of an equivalent for the C idiom "struct of state variables". Are these issues discussed, in a Sun manual, or elsewhere? Is there a better way?
Other desperate questions: does a C compiler that output Javacard bytecode make sense/exists? Or a usable Javacard bytecode assembler?
Francois Grieu

Interesting post.
I don't have a solution to your problem, but caching the session variables arrays in local variable arrays is a good start. This should be only done when the applet is in context, e.g. selected or accessed through the shareable interface. This values should be written back to EEPROM at e.g. deselect or some other important point of time. Do you run into problems if a tear happens? I don't think so since the session variables should be transactional, and a defined point will commit a transaction.
Analyzing the bytecode is a good idea. I know of a view in JCOP Tools (Eclipse plugin) where you can analyze the bytecode and optimize it to your needs.

Session variable

I created a period status session variable which i want to use as a filter in answers. This variable takes note of the last closed period (month - YYYYMDD) when the accounting team closes it in their books. I currently have open periods taking the values of the last closed period and so the client wants these open periods to be removed from the report until the period in closed with accounting hence the use of a filter on the period (month) column. I used this filter eg Time."Fiscal Period" <= VALUEOF(NQ_SESSION."CURR_PER_OPEN") but it is producing this message:
The specified criteria didn't result in any data. This is often caused by applying filters that are too restrictive or that contain incorrect values. Please check your Request Filters and try again. The filters currently being applied are shown below.

Hi,
Try it like this..
Set the default using logical SQL. Select <presentation table>.<presentation
column> from <subject area> where
<presentation table>.<presentationation column> =
valueof(NQ_SESSION.<session variable>)
http://gerardnico.com/wiki/dat/obiee/set_request_variable_dashboard_prompt
http://sureshotstrategies.blogspot.com/2008/07/about-session-variables-in-obiee.html
Thanks
Deva

J2ee session variables

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