RE: Concurrent calls to Session bean methods
I was also wondering about this. Of course since the webcontroller is not an
EJB it is allowed to use the otherwise banned synchronized keyword!
Guy.
-Original Message-
From: The elephantwalker [mailto:[EMAIL PROTECTED]]
Sent: 21 March 2002 04:48
To: Orion-Interest
Subject: RE: Concurrent calls to Session bean methods
John,
Here is the offending class, compliments of the Sun Blueprint team:
public class ShoppingClientControllerWebImpl implements
WebClientController
{
private ShoppingClientControllerLocal sccEjb;
private HttpSession session;
public ShoppingClientControllerWebImpl() {
}
// ... stuff...
//
// the important bit ...
public synchronized EventResponse handleEvent(Event ev)
throws EventException {
return sccEjb.processEvent(ev);
}
}
So you see that the webcontroller is the _only_ access to the
sfsb. And the
only call is synchronized, thus preventing cocurrent calls to
the stateful
session bean.
regards,
the elephantwalker
www.elephantwalker.com
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of
[EMAIL PROTECTED]
Sent: Wednesday, March 20, 2002 12:05 PM
To: Orion-Interest
Subject: RE: Concurrent calls to Session bean methods
I haven't seen the history on this issue, but it interests
me. I had a
quick look at the ShoppingClientControllerEJB class that is
given as an
example by Sun in the Session Facade design pattern, but
couldn't see where
they are synchronizing calls. Can you provide some more clues?
Thanks,
John H.
The elephantwalker
[EMAIL PROTECTED] To:
[EMAIL PROTECTED]
Sent by: cc:
owner-orion-interest@orion Subject: RE:
Concurrent calls to Session bean methods
server.com
03/19/02 10:31 PM
Please respond to
Orion-Interest
Vani,
You can use the petstore trick. Use a facade class which
sychronizes each
call to your session bean. That should do the trick.
This is a _famous_ problem with session beans.
regards,
the elephantwalker
www.elephantwalker.com
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Vani H.S.
Sent: Wednesday, March 20, 2002 12:04 AM
To: Orion-Interest
Subject: Concurrent calls to Session bean methods
Hello All,
I have been trying to deploy an application consisting of
session beans
and mdbs onto orion1.5.4.
But I seem to run into deadlocks, because my session bean
gets called
concurrently. Please can anybody can tell me if there is a
setting to allow
concurrent calls so that, when a session bean method is
called at one time,
the EJB container blocks the concurrent method call and allows it to
proceed
when the previous call has completed?
If not, how should this problem of concurrent calls be
handled in orion?
Please help.
Thanks,
Vani
The allow-concurrent-calls element specifies whether a
stateful session
bean
instance allows concurrent method calls. By default,
allows-concurrent-calls
is false. However, when this value is set to true, the EJB
container blocks
the concurrent method call and allows it to proceed when the
previous call
has completed.
_
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Re: Concurrent calls to Session bean methods
there is a controller webimpl that acts as a facade, and that method is synchronized... [EMAIL PROTECTED] wrote: I haven't seen the history on this issue, but it interests me. I had a quick look at the ShoppingClientControllerEJB class that is given as an example by Sun in the Session Facade design pattern, but couldn't see where they are synchronizing calls. Can you provide some more clues? Thanks, John H. The elephantwalker [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent by: cc: owner-orion-interest@orion Subject: RE: Concurrent calls to Session bean methods server.com 03/19/02 10:31 PM Please respond to Orion-Interest Vani, You can use the petstore trick. Use a facade class which sychronizes each call to your session bean. That should do the trick. This is a _famous_ problem with session beans. regards, the elephantwalker www.elephantwalker.com -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Vani H.S. Sent: Wednesday, March 20, 2002 12:04 AM To: Orion-Interest Subject: Concurrent calls to Session bean methods Hello All, I have been trying to deploy an application consisting of session beans and mdbs onto orion1.5.4. But I seem to run into deadlocks, because my session bean gets called concurrently. Please can anybody can tell me if there is a setting to allow concurrent calls so that, when a session bean method is called at one time, the EJB container blocks the concurrent method call and allows it to proceed when the previous call has completed? If not, how should this problem of concurrent calls be handled in orion? Please help. Thanks, Vani The allow-concurrent-calls element specifies whether a stateful session bean instance allows concurrent method calls. By default, allows-concurrent-calls is false. However, when this value is set to true, the EJB container blocks the concurrent method call and allows it to proceed when the previous call has completed. _ Join the world's largest e-mail service with MSN Hotmail. http://www.hotmail.com
What's the difference between Oracle 9i App Server Release @ and orion 1.5.4?
Subject: What's the difference between Oracle 9i App Server Release @ and orion 1.5.4? From: alt.cybercafes [EMAIL PROTECTED] === This is a multi-part message in MIME format. --=_NextPart_000_0158_01C1D0CA.5046C130 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable What's the difference between Oracle 9i App Server Release @ and orion = 1.5.4? Do they support EJB2.0, etc.? --=_NextPart_000_0158_01C1D0CA.5046C130 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC -//W3C//DTD HTML 4.0 Transitional//EN HTMLHEAD META http-equiv=3DContent-Type content=3Dtext/html; = charset=3Diso-8859-1 META content=3DMSHTML 6.00.2713.1100 name=3DGENERATOR STYLE/STYLE /HEAD BODY DIV PFONT face=3DArial size=3D2What's the difference between Oracle 9i = App Server=20 Release @ and orion 1.5.4/FONT? Do they support EJB2.0, etc.?/P Pnbsp;/P/DIV/BODY/HTML --=_NextPart_000_0158_01C1D0CA.5046C130--
Some more help with SwiftMQ and Orion
Hello All, My earlier message on the same topic got lost, I think. Anyways, I have successfully integrated SwiftMQ with Orion 1.5.4 I have been able to create queues and I am even able to deploy MDBs. I am facing a strange problem. For my MDB, in the orion-ejb-jar.xml, I have given the following settings. message-driven-deployment name=SystemMessageEJB destination-location=java:comp/resource/SwiftMQ/SystemQueue connection-factory-location=java:comp/resource/SwiftMQ/QueueConnectionFactory max-instances=1 min-instances=1 cache-timeout=never / But somehow, when my application runs, I see that the SystemMessageBean's ejbCreate is called once again in the code. I don't know why this is happening. Please can anybody suggest any solution to this problem? Now I am really confused as to whether MDBs are getting created in Orion or SwiftMQ. Why is the setting my orion-ejb-jar.xml getting ignored? Please help. Thanks, Vani _ Join the worlds largest e-mail service with MSN Hotmail. http://www.hotmail.com
Re: What's the difference between Oracle 9i App Server Release @ and orion 1.5.4?
In case there is any confusion, Oracle 9iAS has, among many other things, a j2ee container licensed from the Orion code-base. The j2ee container is OC4J. Besides cost, there are a number of differences - Orion 1.5.4 has more of the ejb2.0 spec implemented, though they are still working on it. OC4J has introduced things like ejb-clustering and has support for j2ee-style connectors and a few more tuning parameters. Cheers Ray --- Orion Newsgroup [EMAIL PROTECTED] wrote: Subject: What's the difference between Oracle 9i App Server Release @ and orion 1.5.4? From: alt.cybercafes [EMAIL PROTECTED] == This is a multi-part message in MIME format. --=_NextPart_000_0158_01C1D0CA.5046C130 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable What's the difference between Oracle 9i App Server Release @ and orion 1.5.4? Do they support EJB2.0, etc.? --=_NextPart_000_0158_01C1D0CA.5046C130 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable !DOCTYPE HTML PUBLIC -//W3C//DTD HTML 4.0 Transitional//EN HTMLHEAD META http-equiv=Content-Type content=text/html; charset=iso-8859-1 META content=MSHTML 6.00.2713.1100 name=GENERATOR STYLE/STYLE /HEAD BODY DIV PFONT face=Arial size=2What's the difference between Oracle 9i App Server Release @ and orion 1.5.4/FONT? Do they support EJB2.0, etc.?/P Pnbsp;/P/DIV/BODY/HTML --=_NextPart_000_0158_01C1D0CA.5046C130-- __ Do You Yahoo!? Yahoo! Movies - coverage of the 74th Academy Awards® http://movies.yahoo.com/
RE: User Manager Questions
Anil, You might try looking at our tutorial on user security ... http://www.elephantwalker.com/rfa?id=404 You will need to get an account, but its free to join. Its important that bit in your applications is followed... META-INF/application.xml --should have the j2ee roles, and java-application client. META-INF/orion-application.xml -- should have the group/role mapping META-INF/principals.xml --- should have the groups listed which are in your user database, and permissions for their access ... regards, the elephantwalker www.elephantwalker.com -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Anil D Sent: Thursday, March 21, 2002 6:16 AM To: Orion-Interest Subject: User Manager Questions Hi all I have some questions regarding the use of UserManager I have implemented a custom User Manager in our application and specified it in the orion-application.xml. On server startup the init method of the UserManager is executed, but while trying to login from an Application Client(Swing) it wasnt going to any of the Methods in my Custom User Manager. It was only allowing the users in my principals.xml. Is it supposed to work this way? How do I allow the usernames in my databases to login? I also tried to use the RoleManager. But when I try to lookup RoleManager from the Client side it throws a name not found exception. TIA Anil
EJB failover/replication?
Hello, I'm starting to evaluate Orion as a application server for a project and I'm trying to figure out if/how Orion supports EJB failover. Oracle/AS appears to, but I can't tell if thats a feature that they added on top of Orion. If EJB failover/replication is supported, could somebody point me to any documentation? Thanks, Michael
Re: Concurrent calls to Session bean methods
ello,
What if the application is deployed in a cluster (even the web tier)? Would
that nullify the synchronised effect?
cheers
romen
- Original Message -
From: The elephantwalker [EMAIL PROTECTED]
To: Orion-Interest [EMAIL PROTECTED]
Sent: Thursday, March 21, 2002 3:47 PM
Subject: RE: Concurrent calls to Session bean methods
John,
Here is the offending class, compliments of the Sun Blueprint team:
public class ShoppingClientControllerWebImpl implements
WebClientController
{
private ShoppingClientControllerLocal sccEjb;
private HttpSession session;
public ShoppingClientControllerWebImpl() {
}
// ... stuff...
//
// the important bit ...
public synchronized EventResponse handleEvent(Event ev)
throws EventException {
return sccEjb.processEvent(ev);
}
}
So you see that the webcontroller is the _only_ access to the sfsb. And
the
only call is synchronized, thus preventing cocurrent calls to the stateful
session bean.
regards,
the elephantwalker
www.elephantwalker.com
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of
[EMAIL PROTECTED]
Sent: Wednesday, March 20, 2002 12:05 PM
To: Orion-Interest
Subject: RE: Concurrent calls to Session bean methods
I haven't seen the history on this issue, but it interests me. I had a
quick look at the ShoppingClientControllerEJB class that is given as an
example by Sun in the Session Facade design pattern, but couldn't see
where
they are synchronizing calls. Can you provide some more clues?
Thanks,
John H.
The elephantwalker
[EMAIL PROTECTED] To:
[EMAIL PROTECTED]
Sent by: cc:
owner-orion-interest@orion Subject: RE:
Concurrent calls to Session bean methods
server.com
03/19/02 10:31 PM
Please respond to
Orion-Interest
Vani,
You can use the petstore trick. Use a facade class which sychronizes each
call to your session bean. That should do the trick.
This is a _famous_ problem with session beans.
regards,
the elephantwalker
www.elephantwalker.com
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Vani H.S.
Sent: Wednesday, March 20, 2002 12:04 AM
To: Orion-Interest
Subject: Concurrent calls to Session bean methods
Hello All,
I have been trying to deploy an application consisting of session beans
and mdbs onto orion1.5.4.
But I seem to run into deadlocks, because my session bean gets called
concurrently. Please can anybody can tell me if there is a setting to
allow
concurrent calls so that, when a session bean method is called at one
time,
the EJB container blocks the concurrent method call and allows it to
proceed
when the previous call has completed?
If not, how should this problem of concurrent calls be handled in orion?
Please help.
Thanks,
Vani
The allow-concurrent-calls element specifies whether a stateful session
bean
instance allows concurrent method calls. By default,
allows-concurrent-calls
is false. However, when this value is set to true, the EJB container
blocks
the concurrent method call and allows it to proceed when the previous call
has completed.
_
Join the world's largest e-mail service with MSN Hotmail.
http://www.hotmail.com
Re: EJB failover/replication?
I believe that particular feature was added on top of Orion - not sure if Orion will add that at a future date. Cheers Ray --- Michael Crozier [EMAIL PROTECTED] wrote: Hello, I'm starting to evaluate Orion as a application server for a project and I'm trying to figure out if/how Orion supports EJB failover. Oracle/AS appears to, but I can't tell if thats a feature that they added on top of Orion. If EJB failover/replication is supported, could somebody point me to any documentation? Thanks, Michael __ Do You Yahoo!? Yahoo! Movies - coverage of the 74th Academy Awards® http://movies.yahoo.com/
Auto-reply: EJB failover/replication?
I am on vacation from 3/1 to 3/22. Please contact my manger, Wendy Liau for any issue. Sam ---BeginMessage--- Hello, I'm starting to evaluate Orion as a application server for a project and I'm trying to figure out if/how Orion supports EJB failover. Oracle/AS appears to, but I can't tell if thats a feature that they added on top of Orion. If EJB failover/replication is supported, could somebody point me to any documentation? Thanks, Michael ---End Message---
RE: Concurrent calls to Session bean methods
The sfsb has a _session_ which is bound to the client. So the client could
be anywhere, irregardless of a cluster.
oc4j has a last method state replication which makes sure that all sfsb's
have the same _session_.
A slsb wouldn't care, and doesn't have the same problem with concurrency,
since they are not reentrant.
regards,
the elephantwalker
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Romen Law
Sent: Thursday, March 21, 2002 2:33 PM
To: Orion-Interest
Subject: Re: Concurrent calls to Session bean methods
ello,
What if the application is deployed in a cluster (even the web tier)? Would
that nullify the synchronised effect?
cheers
romen
- Original Message -
From: The elephantwalker [EMAIL PROTECTED]
To: Orion-Interest [EMAIL PROTECTED]
Sent: Thursday, March 21, 2002 3:47 PM
Subject: RE: Concurrent calls to Session bean methods
John,
Here is the offending class, compliments of the Sun Blueprint team:
public class ShoppingClientControllerWebImpl implements
WebClientController
{
private ShoppingClientControllerLocal sccEjb;
private HttpSession session;
public ShoppingClientControllerWebImpl() {
}
// ... stuff...
//
// the important bit ...
public synchronized EventResponse handleEvent(Event ev)
throws EventException {
return sccEjb.processEvent(ev);
}
}
So you see that the webcontroller is the _only_ access to the sfsb. And
the
only call is synchronized, thus preventing cocurrent calls to the stateful
session bean.
regards,
the elephantwalker
www.elephantwalker.com
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of
[EMAIL PROTECTED]
Sent: Wednesday, March 20, 2002 12:05 PM
To: Orion-Interest
Subject: RE: Concurrent calls to Session bean methods
I haven't seen the history on this issue, but it interests me. I had a
quick look at the ShoppingClientControllerEJB class that is given as an
example by Sun in the Session Facade design pattern, but couldn't see
where
they are synchronizing calls. Can you provide some more clues?
Thanks,
John H.
The elephantwalker
[EMAIL PROTECTED] To:
[EMAIL PROTECTED]
Sent by: cc:
owner-orion-interest@orion Subject: RE:
Concurrent calls to Session bean methods
server.com
03/19/02 10:31 PM
Please respond to
Orion-Interest
Vani,
You can use the petstore trick. Use a facade class which sychronizes each
call to your session bean. That should do the trick.
This is a _famous_ problem with session beans.
regards,
the elephantwalker
www.elephantwalker.com
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Vani H.S.
Sent: Wednesday, March 20, 2002 12:04 AM
To: Orion-Interest
Subject: Concurrent calls to Session bean methods
Hello All,
I have been trying to deploy an application consisting of session beans
and mdbs onto orion1.5.4.
But I seem to run into deadlocks, because my session bean gets called
concurrently. Please can anybody can tell me if there is a setting to
allow
concurrent calls so that, when a session bean method is called at one
time,
the EJB container blocks the concurrent method call and allows it to
proceed
when the previous call has completed?
If not, how should this problem of concurrent calls be handled in orion?
Please help.
Thanks,
Vani
The allow-concurrent-calls element specifies whether a stateful session
bean
instance allows concurrent method calls. By default,
allows-concurrent-calls
is false. However, when this value is set to true, the EJB container
blocks
the concurrent method call and allows it to proceed when the previous call
has completed.
_
Join the world's largest e-mail service with MSN Hotmail.
http://www.hotmail.com
RE: EJB failover/replication?
Michael, Orion has a loadbalancer for the web-tier, and this has failure detection, and is http session aware. If your application is deployed on several island's, your web-tier is virutally immortal. Likewise, entity beans and slsb ejb's deployed in the same vm's will be replicated. For beans which are deployed on remote machines, the Orion ormi has a built-in failover capability. If you provide a list of ormi servers in your rmi.xml file, Orion will try each one, in turn, if one is unavailable. So entity and slsb's have complete fail-over. However, most who use orion use ejb's in the same container as the web teir. Ormi can also be clustered using multi-casting. Oc4j has sfsb fail-over, as I have seen this demonstrated at Oracle Open World by Larry himself. I am still checking if this will work in 1.5.4. Key bit is the replication tag in the orion-ejb-jar.xml. Apparently, it only works for the default state. Oracle describes three different methods, vm shutdown replication, end of call replication and a homegrown method call replication. The EndOfCall replication attribute just blows up nicely, so it looks like they have broken this for orion 1.5.4. Still investigating, though. regards, the elephantwalker www.elephantwalker.com -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Michael Crozier Sent: Thursday, March 21, 2002 2:07 PM To: Orion-Interest Subject: EJB failover/replication? Hello, I'm starting to evaluate Orion as a application server for a project and I'm trying to figure out if/how Orion supports EJB failover. Oracle/AS appears to, but I can't tell if thats a feature that they added on top of Orion. If EJB failover/replication is supported, could somebody point me to any documentation? Thanks, Michael
