Is it save to use class variables in stateful application modules?

I've a simple question of understanding: Can I savely use class-variables in stateful application modules?
Consider the following example:
public class myStateFullAppModuleImpl extends ApplicationModuleImpl
private int myVar=0;
public int doMyWork()
myVar++;
return myVar;
Is it save to use "myVar" this way considering AM-pooling? Or should I save "myVar" in the session instead?
Thanks

Please see reply at:
Is it save to use class variables in a stateful application module?

Similar Messages

Is it save to use class variables in a stateful application module?

I've a simple question of understanding: Can I savely use class-variables in stateful application modules?
Consider the following example:
public class myStateFullAppModuleImpl extends ApplicationModuleImpl
private int myVar=0;
public int doMyWork()
myVar++;
return myVar;
Is it save to use "myVar" this way considering AM-pooling? Or should I save "myVar" in the session instead?
Thanks

Remainder of code:
            for (int i=0; i < length; i++)
               org.w3c.dom.Node child = nl.item(i);
               if (child != null && "jbo.counter".equals(child.getNodeName()))
                  getSession().getUserData().put(
                     "jbo.counter", child.getFirstChild().getNodeValue());
                  int counterInt = getCounterValue();
                  counterInt++;
                  getSession().getUserData().put(
                     "jbo.counter", String.valueOf(counterInt));
                  break;
      public void prepareSession(oracle.jbo.Session session)
         super.prepareSession(session);
         try
            int counterInt = getCounterValue();
            counterInt++;
            getSession().getUserData().put("jbo.counter", String.valueOf(counter
Int));
         catch (Exception e)
            e.printStackTrace();
      public int getCounterValue()
         int counterInt = 0;
         try
            String counter = (String)getSession().getUserData().get("jbo.counter[i][pre]Long postings are being truncated to ~1 kB at this time.

Where can i save the use's data of external application?

where can i save the use's data of external application?and whether will it accumulate to some synchronic problem?
The way i am doing by is to save the information in providersession by initSession() of ProviderInstance,then to get the information back by using session.getAttribute(),which is in jsp. is it right?and what problem will be caused?
so i want to know what is the standard method to use the information in external application to page.

Hi Alf,
Please have a look at the POINT portlets. most of them are based on external apps. That could give you a fair enough idea of how to go about with your designs.
http://www.oracle.com/technology/products/ias/portal/point.html
thanks,
Harsha

Using a variable with "tell application"

I'd like to use a variable (app_name) with "tell application" in the following function:
on getAdobeDoc(app_name)
tell application app_name
tell current document
return (name as Unicode text)
end tell
end tell
end getAdobeDoc
but I'm getting the following error in Script Editor
"Expected end of line but found class name." with the word "document" highlighted.
Are you allowed to use variables in "tell application"? All Adobe CS apps seem to use the same format to get the document name so I'd like to use one function to get them.

If the application might have a different name on the target machine (for example, if it has a version number added), you can use an application's bundle identifier (or creator code) to set the variable, in which case the using terms from statement tells AppleScript the application (on your machine) to get the dictionary terms from. If the application you are using terms from has a dictionary identical to your variable, everything should work the same. The following example uses a variable (called, appropriately enough, TexttEdit) for the TextEdit application:
<pre style="
font-family: Monaco, 'Courier New', Courier, monospace;
font-size: 10px;
margin: 0px;
padding: 5px;
border: 1px solid #000000;
width: 720px;
color: #000000;
background-color: #FFDDFF;
overflow: auto;"
title="this text can be pasted into the Script Editor">
tell application "Finder" to set TextEdit to the name of application file id "com.apple.TextEdit"
tell application TextEdit
using terms from application "TextEdit"
launch
make new document with properties {text:"This is a test"}
end using terms from
end tell
</pre>

How to use bind variables in JSP applications ?

Hi,
How will i use bind variables in jsp applicaions ?
Any links that give a clear understanding ?
TIA,
jj

Hi,
Try this link, this may help you.
http://www.oracle-base.com/articles/misc/WebScriptingForOracle.php
Thanks

Help please! Using classes in large swing applications.

I am building a fairly large swing application. The class that builds the main frame for the application is getting extremely long with code because I have so many seperate JPanels. I'm using JDialogs wherever possible, but in many cases I need a JPanel within my main frame. I've been trying to build these panels within their own seperate classes, but it seems that the components are not being drawn. Any help or a small example would be great!

So... The question is: You don't know how to use JPanels built in other classes?
You should probably just try to find some sort of reference code and work from that. It's really not that hard

Deploying large applications and common used classes

I've got an application containing EntityBeans, statefull/stateless
SessionBeans, and a Webapplication. Every component is packed in a jar File
and all together in an EAR-File as an application.
Those EJBs share some common classes, for example:
EjbA in A.jar and EjbB in B.jar share a Helperclass C.
Where do I put this class C? I try to avoid to put this class C in the
Classpath of the application server. And when I put C in both jar-Files I
got a ClassNotFoundException in one of the EJBs. I'm using WLS 6.0.
Any ideas? Thanx in advance.

FYI, this is fixed in 6.1
Torsten Friebe wrote:
Hi Daniel,
thanks, this article answers my question. But does WLS 6.0 or 6.1 allready
support J2EE Packaging as described in J2EE 1.3 Spec (PFD3) Chapter 8?
Cheers
Torsten
"Daniel Hoppe" <[email protected]> schrieb im Newsbeitrag
news:[email protected]..
Hi Torsten,
there is no really good solution so far. Check out this link, it
elaborates this topic in detail.
http://www.onjava.com/pub/a/onjava/2001/06/26/ejb.html
Cheers,
Daniel
-----Ursprüngliche Nachricht-----
Von: Torsten Friebe [mailto:[email protected]]
Bereitgestellt: Freitag, 29. Juni 2001 11:59
Bereitgestellt in: environment
Unterhaltung: deploying large applications and common used classes
Betreff: deploying large applications and common used classes
I've got an application containing EntityBeans, statefull/stateless
SessionBeans, and a Webapplication. Every component is packed
in a jar File
and all together in an EAR-File as an application.
Those EJBs share some common classes, for example:
EjbA in A.jar and EjbB in B.jar share a Helperclass C.
Where do I put this class C? I try to avoid to put this class C in the
Classpath of the application server. And when I put C in both
jar-Files I
got a ClassNotFoundException in one of the EJBs. I'm using WLS 6.0.
Any ideas? Thanx in advance.

Using volatile variables in j2me

Hi
I was wondering what are the consequences of using volatile variables in j2me application.
Can someone elaborate on the issue?

Not sure what you mean by consequances but I use them for basically communicating with Threads with good success.
Do you have some specific concerns about them?

Using a variable from one class in another

For learning purposes, I thought I'd have a stab at making a role-playing RPG.
The first class I made was the Player class;
public class Player
     public static void main(String[] args)
          // [0] being base points and [1] being skill points
          int[] points = {50, 10};
          // Elements in statNames are relevent to stats, so stats[0] is health, and so on
          String[] statNames = {"Health", "Mana", "Attack", "Magic", "Craft"};
          int[] stats = new int[5];
     public static String setName()
          Scanner input = new Scanner(System.in);
          System.out.print("Character name: ");
          String name = input.nextLine();
          return name;
     public static void setHealth(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Health (" + points[0] + " base points remanining): ");
          stats[0] = input.nextInt();
          points[0] -= stats[0];
        public static void setMana(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Mana (" + points[0] + " base points remanining): ");
          stats[1] = input.nextInt();
          points[0] -= stats[1];
     public static void setAttack(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Attack (" + points[1] + " skill points remanining): ");
          stats[2] = input.nextInt();
          points[1] -= stats[2];
     public static void setMagic(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Magic (" + points[1] + " skill points remanining): ");
          stats[3] = input.nextInt();
          points[1] -= stats[3];
     public static void setCraft(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Craft (" + points[1] + " skill points remanining): ");
          stats[4] = input.nextInt();
          points[1] -= stats[4];
     public static void setStats(int[] points, int[] stats)
          setHealth(points, stats);
          setMana(points, stats);
          setAttack(points, stats);
          setMagic(points, stats);
          setCraft(points, stats);
     public static void charSummary(String name, String[] statNames, int[] stats)
          System.out.println("\n------ " + name);
          for(int index = 0; index < stats.length; index++)
               System.out.println(statNames[index] + ":\t" + stats[index]);
}And that would be used in the Play class;
public class Play
     public static void main(String[] args)
          Player player = new Player();
          String name = player.setName();
          player.setStats(points, stats);
     }     But I'm not sure how the Play class will get the arrays from the Player class. I tried simply putting public in front of the them, for example;
public String[] statNames = {"Health", "Mana", "Attack", "Magic", "Craft"};But I get an illegal start of expression error.
I may have taken the wrong approach to this all together, I'm completely new, so feel free to suggest anything else. Sorry for any ambiguity.
Edited by: xcd on Jan 6, 2010 8:12 AM
Edited by: xcd on Jan 6, 2010 8:12 AM

HI XCD ,
what about making Player class as
public class Player
          // [0] being base points and [1] being skill points
          int[] points = {50, 10};
          // Elements in statNames are relevent to stats, so stats[0] is health, and so on
          public String[] statNames = {"Health", "Mana", "Attack", "Magic", "Craft"};
          int[] stats = new int[5];
     public String setName()
          Scanner input = new Scanner(System.in);
          System.out.print("Character name: ");
          String name = input.nextLine();
          return name;
     public void setHealth(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Health (" + points[0] + " base points remanining): ");
          stats[0] = input.nextInt();
          points[0] -= stats[0];
        public void setMana(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Mana (" + points[0] + " base points remanining): ");
          stats[1] = input.nextInt();
          points[0] -= stats[1];
     public void setAttack(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Attack (" + points[1] + " skill points remanining): ");
          stats[2] = input.nextInt();
          points[1] -= stats[2];
     public void setMagic(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Magic (" + points[1] + " skill points remanining): ");
          stats[3] = input.nextInt();
          points[1] -= stats[3];
     public void setCraft(int[] points, int[] stats)
          Scanner input = new Scanner(System.in);
          System.out.print("Craft (" + points[1] + " skill points remanining): ");
          stats[4] = input.nextInt();
          points[1] -= stats[4];
     public void setStats(int[] points, int[] stats)
          setHealth(points, stats);
          setMana(points, stats);
          setAttack(points, stats);
          setMagic(points, stats);
          setCraft(points, stats);
     public void charSummary(String name, String[] statNames, int[] stats)
          System.out.println("\n------ " + name);
          for(int index = 0; index < stats.length; index++)
               System.out.println(statNames[index] + ":\t" + stats[index]);
     }and Play class
public class Play
     public static void main(String[] args)
          Player player = new Player();
          String name = player.setName();
          player.setStats(points, stats);
     }Now you can access names , you can't assign keyword to variable into method scope , make it class variable .
Hope it help :)

Using a variable from one class to another

Hi !
I've a class called ModFam (file ModFam.java) where I define a variable as
protected Connection dbconn;
Inside ModFam constructor I said:
try
String url = "jdbc:odbc:baselocal";
Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" );
dbconn = DriverManager.getConnection(url);
System.err.println("Connection successful");
} ..... rest of code
This class define a TabbedPane as follows:
tabbedPane.addTab("Welcome",null,new Familias(),"Familias");
As you can see it call a new instance of the Familias class (file Familias.java).
This constructor will try to connect with the DB to populate a combo box with some data retireved from the DB.
If I do
Statement stmt;
stmt = dbconn.createStatement();
inside Familias constructor I receive the message
Familias.java:50: cannot resolve symbol
symbol : variable dbconn
location: class fam.Familias
stmt = dbconn.createStatement();
at compile time.
While I can�t use a variable defined as "protected" in one class of my package on another class of the same package ?
How could I do ?
Thanks in advance
<jl>

Familias doesn't have a reference to ModFam or the Connection.
So change the constructor in Familias to be
public class Familias {
private ModFam modFam;
public Familias(ModFam m) {
modFam = m;
// ... somewhere else in the code
Statement stmt = modFam.dbconn.createStatement();
}or
public class Familias {
private Connection dbconn;
public Familias(Connection c) {
dbconn = c;
// ... somewhere else in the code
Statement stmt = dbconn.createStatement();
}And when you instantiate Familias it should then be
new Familias(this) // ModFam reference
or
new Familias(dbconn)

How do I use a variable from an Interface class?

Right now I have three classes. First class is called Game and it extends my second class call Parent and also implements my third class call Source. Source is an interface class. I have a variable that I want to use in my Source class named Checker. Now, How do I go among using that variable from my Game class? What should the code look like?
ex.
public class Game extends Parent implements Source
need help badly....

ok, what I forgot to tell you guys is that my variable
in my interface class is a boolean type(true or
false). It is set to true now. But I want it to change
to false when a user triggers a button in the Game
class. How do I do this? You don't because you can't. If you have a varaible declared in an interface it must be static and final. It cannot, therefore, be changed. Better head back to the drawing board.

How to use Public variables in other classes

Please have a look at the program.
In the below program, i want to use the variable 'name' in the class cl_airplane1 implementation under the method aircraft to display 'BRITISH AIRWAYS' which i am passing through the object AIR1.
The variable 'name' is declared under public section of the class cl_airplane. I do not want to use inheritance. Can i do this.
*&             CLASS DEFINITION
CLASS cl_airplane DEFINITION.
PUBLIC SECTION.
    METHODS set IMPORTING im_name TYPE string
                           im_weight TYPE i.
    METHODS display.
    DATA name TYPE string.
PRIVATE SECTION.
    DATA weight TYPE i.
ENDCLASS.
*&                   CLASS IMPLEMENTATION
CLASS cl_airplane IMPLEMENTATION.
*******METHOD SET*****************
METHOD set.
    name = im_name
    weight = im_weight.
ENDMETHOD.
*******METHOD DISPLAY**************
METHOD display.
    WRITE : / ' NAME :', name, ' AND ', 'WEIGHT:', weight.
ENDMETHOD.
ENDCLASS.
*&     END OF CLASS CL_AIRPLANE IMPLEMENTATION
*&             CLASS DEFINITION-CL_AIRPLANE1
CLASS cl_airplane1 DEFINITION .
PUBLIC SECTION.
    METHODS : aircraft IMPORTING im_name1 TYPE string,
              dis1.
ENDCLASS.
*&                   CLASS IMPLEMENTATION
CLASS cl_airplane1 IMPLEMENTATION.
*******METHOD AIRCRAFT
METHOD aircraft.
ENDMETHOD.
********METHOD DIS1
METHOD dis1.
ENDMETHOD.
ENDCLASS.
**********CREATING REFERENCE VARIABLES
DATA : air TYPE REF TO cl_airplane.
DATA : air1 TYPE REF TO cl_airplane1.
START-OF-SELECTION.
***CREATING AN OBJECT OF THE CLASS CL_AIRPLANE
CREATE OBJECT air .
CALL METHOD air->set
    EXPORTING
      im_name   = 'Lufthansa'
      im_weight = '1000'.
CALL METHOD air->display.
***CREATING AN OBJECT OF THE CLASS CL_AIRPLANE1
CREATE OBJECT air1.
CALL METHOD air1->aircraft
    EXPORTING
      im_name1 = 'BRITISH AIRWAYS'.
CALL METHOD air1->dis1.
<removed_by_moderator>
Thanks.
Edited by: Julius Bussche on Jul 30, 2008 3:13 PM

Here is ur solution:
*& Report Z157780_PRG1
REPORT z157780_prg1.
*& CLASS DEFINITION
CLASS cl_airplane DEFINITION.
PUBLIC SECTION.
    METHODS set IMPORTING im_name TYPE string
    im_weight TYPE i.
    METHODS display.
    DATA name TYPE string.
PRIVATE SECTION.
    DATA weight TYPE i.
ENDCLASS.                    "
*& CLASS IMPLEMENTATION
CLASS cl_airplane IMPLEMENTATION.
********METHOD SET******************
METHOD set.
    name = im_name.
    weight = im_weight.
ENDMETHOD.                    "set
********METHOD DISPLAY***************
METHOD display.
    WRITE : / ' NAME :', name, ' AND ', 'WEIGHT:', weight.
ENDMETHOD.                    "display
ENDCLASS.                    "
*& END OF CLASS CL_AIRPLANE IMPLEMENTATION
*& CLASS DEFINITION-CL_AIRPLANE1
CLASS cl_airplane1 DEFINITION INHERITING FROM cl_airplane.
PUBLIC SECTION.
    METHODS : aircraft IMPORTING im_name1 TYPE string,
    dis1.
ENDCLASS.                    "
*& CLASS IMPLEMENTATION
CLASS cl_airplane1 IMPLEMENTATION.
*******METHOD AIRCRAFT
METHOD aircraft.
    name = im_name1.
    WRITE : / ' NAME :', name.
ENDMETHOD.                    "aircraft
********METHOD DIS1
METHOD dis1.
ENDMETHOD.                                                "dis1
ENDCLASS.                    "
**********CREATING REFERENCE VARIABLES
DATA : air TYPE REF TO cl_airplane.
DATA : air1 TYPE REF TO cl_airplane1.
START-OF-SELECTION.
***CREATING AN OBJECT OF THE CLASS CL_AIRPLANE
CREATE OBJECT air .
CALL METHOD air->set
    EXPORTING
      im_name   = 'Lufthansa'
      im_weight = '1000'.
CALL METHOD air->display.
***CREATING AN OBJECT OF THE CLASS CL_AIRPLANE1
CREATE OBJECT air1.
CALL METHOD air1->aircraft
    EXPORTING
      im_name1 = 'BRITISH AIRWAYS'.
CALL METHOD air1->dis1.
Hope That Helps
Anirban M.

Save for previous version 8.5 to 8.2 generates code that crashes Labview (uses classes)

Hello,
I'm working on some java style interfaces for labview for hot swapping of instrumentation for design patterns. When I try to port this code, developed on Labview 8.5 back to labview 8.2, the code it generates crashes labview (both 8.5 and 8.2).
Included is a small snipet of the work that demonstrates this behavior.
It includes to classes:
untitledProject1 - the containing project (version 8.5)
FunctionGeneratorI - Similar to a Java style interface (A class with all Dynamic VI's with no useful functionality)
FunctionGenerator33220a - An intended implementation of Function generator (only a few functions implemented)
and a folder "labview8_2Distribution"
Which contains the port of the 8.5 code to 8.2.
To recreate the error:
A.
1. Open "labview8_2Distribution\Users\Laptop\Desktop\object\Untitled Project 1" (8.2 save)
2. Verify it crashes labview 8.5 and labview 8.2.
3. Watch labview crash?
B.
1. Open the "Untitled project 1" in the root directory. (Using labview 8.5)
2. Save the project as a labview 8.2 type.
3. Try to open the saved version with 8.5 and 8.2.
4. Watch labview crash?
Greg Sonnenfeld
Attachments:
error.zip ‏885 KB

Hello Karunya,
In regards to your questions:
>Can you post your code? Have you tested this by creating another project?
Do you have an xcontrols in your projects? Do you have typedefs? Do you
have a LVOOP constant on your block diagram? Are you also using Classes?
I cannot post the cost as it is way too big. Not really my code but a spaghetti code from a previous programmer. I think problems saving it to a previous version have to do with a few things:
1) Memory - I have 1 GB of RAM and I am running XP. I notice the available RAM dropping quickly as it is saving and then it blow up.
2) Long Filenames - The directory path of the original file is incorporated into the saved "previous version" of the code. While a good design, it does make the file/path a bit longer when saving
3) One of teh things it saves is the drivers and their menus. This is due to the drivers being in a subdirectory of the original code and not in the c:\program files\national instruments\labview 8.5\instr.lib directory. I saw this when I tried to save the file as an LLB.
4) If I work with smaller parts of the code without long paths, it saves fine.
There probably are xcontrols, definitely typedefs, no LVOOP's or Classes. Hope you can do something with all this. It just seems that converting to a later version of the code should be reversable. Thanks.
Michael

How to access an element using its name or id if it is not a class variable?

I am trying to retrieve the element I added to my UI in a different function. I am using actionscript 3. I know I can put the variable into a class variable, so it can be access anywhere in the class, but I have too many elements. Is there anyway I could access them without putting them into class variable?
Thanks.
public class Test extends SkinnableContainer{
// private var image:Image; <-- I try not to do this, too messy
private function func1() {
    var image:Image = new Image();
    addElement(image);
private function func2() {
    var image:Image = /* how to get the element from my UI without putting into class variable */

Here is what works for me:
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
               xmlns:s="library://ns.adobe.com/flex/spark"
               xmlns:mx="library://ns.adobe.com/flex/mx"
               creationComplete="init()"
               minWidth="955" minHeight="600">
    <fx:Declarations>
        
    </fx:Declarations>
    <fx:Script>
        <![CDATA[
            import spark.components.Image;
            private var image:Image;
            private function init():void
                image = new Image();
                addElement(image);
                trace(this["image"]);
        ]]>
    </fx:Script>
</s:Application>

How to declare java.lang.Class variable that can be used in Enum.valueOf(.)

As per subject -- we have a need to declare variable in class that will hold enum's Class object. At some point we want to use this variable as a Class argument for Enum.valueOf(.) which has the following signature:
public static <T extends Enum<T>> T valueOf(Class<T> enumType, String name) {..}So far we cannot come up with a workable solution.
private final Class<? extends Enum<?>> propertyClass;doesn't work (apparently because second ? should in fact be the same as first ? -- which works with T for class/method templates, but cannot be used for variables). Error message (in Eclipse) is:
Bound mismatch: The generic method valueOf(Class<T>, String) of type Enum<E> is not applicable for the arguments (Class<capture#13-of ? extends Enum<?>>, String). The inferred type capture#13-of ? extends Enum<?> is not a valid substitute for the bounded parameter <T extends Enum<T>>
So what would be the proper way to declare the variable?
Thanks in advance!

the enum.valueof method is a little weird. they implemented it so it is nice and "safe". if you don't care about that safety, you can probably work with raw types for that bit of code and get the call to go through. you just won't have any type safety on the result.

Is it save to use class variables in stateful application modules?

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