Problem with multiple threads accessing the same Image

I'm trying to draw into one Image from multiple threads. It works fine for a while, but then suddenly, the image stops updating. Threads are still running but the image won't update. I'm using doublebuffering and threads are simply drawing counters into Image with different speed.
It seems like the Image gets deadlocked or something. Anyone have any idea what's behind this behavior or perhaps better solution to do such thing.
Any help will be appreciated.

Sorry Kglad, I didn't mean to be rude. With "No coding
errors" I meant the animation itself runs with no errors. I'm sure
you could run the 20 instances with no freezing (that's why I put
the post :) ) But I'm affraid it is an animation for a client, so I
cannot distribute the code.
Perhaps I didnt explain the situation clearly enough (in part
because of my poor english...).-
- By 20 instances I mean 20 separated embedded objects in the
html
- The animation is relatively simple. A turned on candle, in
each cycle I calculate the next position of the flame (that
oscilates from left to right). The flame is composed by 4
concentric gradients. There is NO loops, only an 'onEnterFrame'
function refreshing the flame each time.
- It's true that I got plenty variables at the _root level.
If that could be the problem, how can I workaround it?
- It is my first time trying to embed so many objects at the
same time too. No idea if the problem could be the way I embed the
object from the html :(
- The only thing I can guess is that when a cycle of one of
the object is running, the other 19 objects must wait their turn.
That would explain why the more instances I run, the worst results
I get. In that case, I wonder if there's a way to run them in a
kind of asynchronous mode, just guessing...
Any other comment would be appreciated. Anyway, thanks a lot
everybody for your colaboration.

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Multiple threads access the same method.

Hello,
I have been trying for a long time to find out multiple threads access the shared data.
I have written a sample code, there I my intention is that method has to be accessed
onlny one thread at a time., mean one thread finished the job, then next thread can
access the shared source. But for this code I am not getting the desired out put what I want. But if I am using synchronized block I am getting the output. Please correct where I got mistake. Please see my code.
public class TestThread implements Runnable {
     Shared r;
     public TestThread() {
          r = new Shared();
     public static void main(String args[]) {
          Thread t1 = new Thread(new TestThread());
          Thread t2 = new Thread(new TestThread());
          t1.setName("A");
          t2.setName("B");
          t1.start();
          t2.start();
      * (non-Javadoc)
      * @see java.lang.Runnable#run()
     @Override
     public void run() {
          // TODO Auto-generated method stub
          r.count();
class Shared {
     public synchronized void count() {
          String name = Thread.currentThread().getName();
          System.out.println(name + ":accessed...");
          try {
               for (int i = 0; i < 5; i++) {
                    System.out.println(name + ": " + i);
          } catch (Exception e) {
               // TODO: handle exception
}Thanks
Bhanu lakshmi.

It depends on what you synchronize. Non-static methods synchronize on the object, so if you're using several objects, you'll be able to call each from their own thread.
Make your method synchronized or use only a single object and see the difference.

Problems with multiple connections in the same transaction

Hi all !
          I'm have two questions regarding the way weblogic handles multiple
          connections.
          1) first, I don't understand why weblogic always create a new Managed
          Connection when I'm asking for 2 connection handles on the same connection
          factory and with the same connectionRequestInfo. Isn't it supposed to share
          connections ?
          For instance, the following snippet of code results in the creation of 2
          managed connections:
          ConnHandle conn1 = myCF.getConnection(myRequInfo);
          ConnHandle conn2 = myCF.getConnection(myRequInfo);
          The class corresponding to myRequInfo does implement the equals and hash
          method, so that weblogic's connection manager could use them to check that
          the queried connections are the same, and thus could share a single
          ManagedConnection between multiple connection handles. Apparantly it does
          not do that...
          2) OK, I just let weblogic create the 2 managed connections, but... My use
          of the connections is as part of a transaction. Here is what happens:
          ConnHandle conn1 = myCF.getConnection(myRequInfo);
          // a new managedConn1 is instanciated. the following happens (just a
          description)
          // xar1 = managedConn1.getXAResource()
          // xar1.start(NOFLAGS)
          // I use the conn1 handle
          conn1.close();
          //xar1.end(SUSPEND)
          ConnHandle conn2 = myCF.getConnection(myRequiInfo);
          // a new managed connection managedConn2 is instanciated.
          // xar2 = managedConn2.getXAResource();
          // xar2.start(RESUME)
          // I use conn2 handle
          conn2.close();
          // xar2.end(SUSPEND);
          // my bean returns from the remote invocation
          // the client of the bean asks to commit (using UerTransaction.commit on the
          client side)
          // xar2.end(SUCCESS)
          // xar2.commit(onePhase=true);
          // managedConn2.cleanup();
          And that's all. So, as one can see, managedConn1.cleanup was never called.
          When looking in the weblogic console, I can see that I have one connection
          with 0 handle and one with 1 handle, deemed as still being in a transaction.
          So, the conenction manager apparantly loses a managed connection during the
          transaction. And it's very very bad because after a couple of transactions,
          I'm running out of managed connections (I had set a limit of 10).
          Any one has seen such a weird behavior ? Is this a problem on my side, or
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          I ran another test. This time I have a bean that makes use of a connector
          once per method invocation. The bean method invoked is "sayHello" and it
          gets a connection to the EIS, perform an operation on it and release it. The
          connector I developed uses XA transactions.
          My test client just calls 3 times myBean.sayHello().
          I can distinguish two cases:
          1) first, the client doesn't do transaction demarcation. In this case, since
          the sayHello method is marked as requiring transaction, the folowing happens
          in the bean:
          // **** first invocation of the bean
          connHandle = myCF.getConnection();
          // managedConn1 is instanciated
          // xar1 = managedConn1.getXAResource()
          // xar1.start(NOFLAGS);
          // managedConn1.getConnection gives a connection handle
          connHandle.doSomeWork();
          connHandle.close()
          // xar1.end(SUCCESS);
          // the bean returns from its invocation
          // xar1.commit(onePhase=true)
          // managedConn1.cleanup()
          // **** second invocation of the bean
          connHandle = myCF.getConnection();
          // managedConnectionFactory.matchManagedConnection is called. It returns the
          managed connection (managedConn1) that is in the passed set
          // xar1 = managedConn1.getXAResource()
          // xar1.start(NOFLAGS);
          // managedConn1.getConnection gives a connection handle
          connHandle.doSomeWork();
          connHandle.close
          // xar1.end(SUCCESS);
          // the bean returns from its invocation
          // xar1.commit(onePhase=true)
          // managedConn1.cleanup()
          // **** third invocation of the bean
          connHandle = myCF.getConnection();
          // managedConnectionFactory.matchManagedConnection is called. It returns the
          managed connection (managedConn1) that is in the passed set
          // xar1 = managedConn1.getXAResource()
          // xar1.start(NOFLAGS);
          // managedConn1.getConnection gives a connection handle
          connHandle.doSomeWork();
          connHandle.close
          // xar1.end(SUCCESS);
          // the bean returns from its invocation
          // xar1.commit(onePhase=true)
          // managedConn1.cleanup()
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          the connection manager instanciates 3 managed connections, calls start/end
          on each XAResource corresponding to each managed connection, calls commit
          once, but also calls cleanup only once, leaving 2 lost managed connections
          The client looks like this:
          UserTransaction utx = context.lookup("javax/transaction/UserTransaction");
          utx.begin();
          MyBean myBean = ctx.lookup(".......");
          myBean.sayHello();
          myBean.sayHello();
          myBean.sayHello();
          utx.commit();
          on the server the following happens:
          // **** first invocation of the bean
          connHandle = myCF.getConnection();
          // managedConn1 is instanciated
          // xar1 = managedConn1.getXAResource()
          // xar1.start(NOFLAGS);
          // managedConn1.getConnection gives a connection handle
          connHandle.doSomeWork();
          connHandle.close()
          // xar1.end(SUSPEND);
          // the bean returns from its invocation
          // **** second invocation of the bean
          connHandle = myCF.getConnection();
          // managedConn2 is instanciated
          // xar2 = managedConn2.getXAResource()
          // xar1.isSameRM(xar2) is called. returns true
          // xar2.start(RESUME);
          // managedConn2.getConnection gives a connection handle
          connHandle.doSomeWork();
          connHandle.close()
          // xar2.end(SUSPEND);
          // the bean returns from its invocation
          // **** third invocation of the bean
          connHandle = myCF.getConnection();
          // managedConn3 is instanciated
          // xar3 = managedConn3.getXAResource()
          // xar2.isSameRM(xar3) is called. returns true
          // xar3.start(RESUME);
          // managedConn3.getConnection gives a connection handle
          connHandle.doSomeWork();
          connHandle.close()
          // xar3.end(SUSPEND);
          // the bean returns from its invocation
          // the client invokes commit on the UserTransaction
          // xar3.end(SUCCESS);
          // xar3.commit(onephase = true);
          // managedConn3.cleanup();
          And so, managedConn1 and managedConn2 got lost in the way...
          What's more puzzling, it's that when monitoring my connector with the
          console, I can see that there are 3 connections. 2 declared as still having
          one handle used and being in transaction, and one not in transaction and
          with 0 active handle. BUT when monitoring the JTA part of the server, I can
          see that there has been 1 transaction that committed, and no connection is
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          connections are still part of a transaction while on the other it says that
          no transactions are currently in flight.
          Thanks for any kind of help on this very bizarre behavior.
          Sylvain

Problem with multiple .swf in the same page

Hi everybody,
I got a small animation written in actionscript 2.0. I need
to load it several times in a webpage (about 20 instances), but
seems to be too many work and the web browser freezes.
Anyway, it's a relatively simple script (not complex
arithmetics per cycle, although two or three color gradient
refreshing), so I think the problem could be the fact of having so
many instances running at the same time...
Is there any way to fix this problem without reducing the
quality of the animation?
Thanks a lot!

Sorry Kglad, I didn't mean to be rude. With "No coding
errors" I meant the animation itself runs with no errors. I'm sure
you could run the 20 instances with no freezing (that's why I put
the post :) ) But I'm affraid it is an animation for a client, so I
cannot distribute the code.
Perhaps I didnt explain the situation clearly enough (in part
because of my poor english...).-
- By 20 instances I mean 20 separated embedded objects in the
html
- The animation is relatively simple. A turned on candle, in
each cycle I calculate the next position of the flame (that
oscilates from left to right). The flame is composed by 4
concentric gradients. There is NO loops, only an 'onEnterFrame'
function refreshing the flame each time.
- It's true that I got plenty variables at the _root level.
If that could be the problem, how can I workaround it?
- It is my first time trying to embed so many objects at the
same time too. No idea if the problem could be the way I embed the
object from the html :(
- The only thing I can guess is that when a cycle of one of
the object is running, the other 19 objects must wait their turn.
That would explain why the more instances I run, the worst results
I get. In that case, I wonder if there's a way to run them in a
kind of asynchronous mode, just guessing...
Any other comment would be appreciated. Anyway, thanks a lot
everybody for your colaboration.

Problem with Multiple Versions of the Same Activex

Hi,
I Installed some "ABC" Activex 9.5 version and 10.1 version in the system.
I have ASP.net webpage which should use only 9.5 version of Activex. But by default 10.1 version is active and invoking by webpage.
Is there any way to enforce from webpage to use only 9.5 version of Activex?
Please let me know if you need more details.
Thanks & Regards,

Hi,
Have you tried to uninstall this Activex in Manage add-on, then install the 9.5 version? Please have a try.
Roger Lu
TechNet Community Support

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So you are saying this is just the way it always works. So as soon as one of our call center agents opens a record all I have to do is create a pending update to any field?
But won't another user be able to open the form and just query that record not knowing another user has it open?

Prevent multiple users accessing the same form

hi,
i am working in forms
i have a requirement like this
if more than one user are using the same form and try to access the same record then the second user should not be able to do transaction
he should be popped up with a msg saying that other user is working on it
can any one suggest how to do this in my form
thanks in advance
selvaraj s

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Two users can use the same form, and can even display the same data record. One of the users can make changes to the record -- Forms locks the row upon the FIRST keystroke in the first field the user begins to change.
Once the row is locked, the second user is free to look at the record, and won't even know if another user has begun making changes. However, if second user tries to change even one field in the record, Forms pops up the message, "Could not reserve record (2 tries). Keep trying? Yes / No"
There are also protections so if the first user actually changes the row and commits, then the second user tries to make a change. Forms will automatically detect whether changes were made, and if so, will undo the change and issue the message, "FRM-40654: Record has been updated by another user. Re-query to see change."
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Can multiple threads share the same cursor in berkeley db java edition?

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Another solution involving no modification of the database structure:
As soon as a user want to access a plan, try to UPDATE the plan record... if it fails, the record was locked
by another user before. When the user has finished with the plan, you can COMMIT or ROLLBACK the changes, which will free the lock for other users.
An advantage of this solution is that if program crashes unexpectedly, there will automatically be a ROLLBACK.
Of course, you need a transaction for this... and perhaps more if you want to separate the 'locking transaction' (virtual update just for restricting access) from the 'operating transaction' (in which you will
do the DB stuff: inserts, updates, deletes, etc.)
Hope this helped,
Regards.

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> The instances will be one active and the other passive, so the services will be up in one server and down in
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