EJB - MDB and Session and Entity - Seem to always run under same Thread

I am working on an application that implemets a connection from an MDB to a Session EJB which inturn connects to a Entity EJB. All connections are impemented as Local Home. I use log4j for tracing and notice that the thread ID reported for all activity is the same "Thread ID: MessageListenerThreadPool : 0" .
This confuses me because I thought that all EJB's would execute under different threads. Have I done something wrong? Have I missinterpreted the EJB implementation? Any opinions would be greatly appreciated!!

Hi Kelly,
This is a slight misinterpretation of the EJB threading requirements. There are a couple different issues as play here. First, the main threading guarantee made by the spec is that a particular instance of an EJB will not be invoked by the container on more than one thread at a time. This is one of the guarantees that simplifies the EJB programming model so that developers don't have to do anything special (e.g. the use of synchronized blocks) to handle concurrent access. Second, the EJB Local programming model requires that invocations have pass-by-reference semantics. Of course, the easiest way for the container to provide that behavior is to literally make the local invocation on the same thread.
The call-flow you're describing touches a single instance from three different beans, so the threading guarantee is not violated. Hope that clears things up a bit.
--ken

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<<
Auto-creating table: create table deployfoo (firstcolumn VARCHAR2(255) not null primary key, secondcolumn VARCHAR2(255) null)
>>>
raghu
JDev Team

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Message was edited by: cornelius

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"Ling Wang" <[email protected]> wrote:
>
Hello,
I am using WL6.1. I need to use weblogic.security.acl.Security.checkPermission
to check if a user has permission to acess an EJB method. I know one
can call
the method and check the exception to see yes or no. But that requires
knowing
the method signature (parameters and return types etc.).
I read the documentation and here is what I got:
ACLs and permissions for WebLogic EJBs differ from ACLs and permissions
for other
kinds of WebLogic Server resources in the following ways:
1. EJB ACLs are configured in the access control properties of the EJB's
deployment
descriptor.
2. Permissions are granted on individual methods of a bean; there are
no predefined
permissions.
3. Permissions on EJBs are granted to Roles, which map to groups in WebLogic
Server.
So if I read it correctly:
1. One does not need to use WL console to configure EJB ACLs? If otherwise,
how
do we do it?. There is no documentation for it.
2. What is the ACLName to use when I call the method weblogic.security.acl.Security.checkPermission(java.security.Principal
principal, java.lang.String aclName,
java.security.acl.Permission permission,
char sep)?
I tried with JNDI name and EJB name and nothing seems to work.
Can anyone help me out?
Thanks.
Ling Wang

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Environment: WLS6.1 SP3, W2K, Oracle 8.1.7, OCI Driver
Hi,
we are experiencing performance problem when getting a connection from a
pool.
Getting a connection from a stateless session bean takes 300-500ms whereas
it takes 15ms
from an entity bean (local). Both session and entity beans are deployed in
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bla bla bla ...
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Arnaud
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<resource-ref>
<res-ref-name>jdbc/XXX</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
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<res-ref-name>jdbc/YYY</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Application</res-auth>
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WLS specific
<reference-descriptor>
<resource-description>
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<jndi-name>jdbc/MyDataSource</jndi-name>
</resource-description>
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<ejb-ref-name>ejb/XXX</ejb-ref-name>
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Hi Arnaud,
"Arnaud Benjacar" <[email protected]> wrote in message news:[email protected]...
<JDBCConnectionPool DriverName="oracle.jdbc.driver.OracleDriver"
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to change it to:
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Regards,
Slava Imeshev
>
>
>
"Slava Imeshev" <[email protected]> wrote in message
news:[email protected]...
Hi Arnaud,
Could you post an extract from config.xml in part of the connection
pools and datasources? I'm asking because the configuration
you have may be not tailored to best performance.
Regards,
Slava Imeshev
"Arnaud Benjacar" <[email protected]> wrote in message
news:[email protected]...
Environment: WLS6.1 SP3, W2K, Oracle 8.1.7, OCI Driver
Hi,
we are experiencing performance problem when getting a connection from a
pool.
Getting a connection from a stateless session bean takes 300-500mswhereas
it takes 15ms
from an entity bean (local). Both session and entity beans are deployedin
the same ear.
In both cases we're getting the datasource using the following codesnippet
Properties p = new Properties();
bla bla bla ...
Context ic = new InitialContext(p);
DataSource ds = (DataSource) ic.lookup("java:comp/env/jdbc/XXX");
and
DataSource ds = (DataSource) ic.lookup("java:comp/env/jdbc/YYY");
When getting the connection, we are experiencing the speed difference
described above.
connection conn = ds.getConnection();
Why do we have this difference? We have the reference to the datasource
already.
There is no further JNDI lookup. Is there something we are missing?
Thanks
Arnaud
Entity descriptor
<resource-ref>
<res-ref-name>jdbc/XXX</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Application</res-auth>
</resource-ref>
WLS specific
<reference-descriptor>
<resource-description>
<res-ref-name>jdbc/XXX</res-ref-name>
<jndi-name>jdbc/MyDataSource</jndi-name>
</resource-description>
</reference-descriptor>
Session descriptor
<resource-ref>
<res-ref-name>jdbc/YYY</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Application</res-auth>
</resource-ref>
WLS specific
<reference-descriptor>
<resource-description>
<res-ref-name>jdbc/YYY</res-ref-name>
<jndi-name>jdbc/MyDataSource</jndi-name>
</resource-description>
<ejb-local-reference-description>
<ejb-ref-name>ejb/XXX</ejb-ref-name>
<jndi-name>ejb/XXXLocal</jndi-name>
</ejb-local-reference-description>
</reference-descriptor>

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Message was edited by:
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kapil khanna wrote:
In our app a user is authenticated via the web container. The web layer then makes
calls to various session EJB's.
In our session bean, calls to sessionContext.getCallerPrincipal().getName() sometimes
returns "SYSTEM" instead of
the principal's name that was authenticated at the web container level.
In our entity beans, calls to entityContext.getCallerPrincipal().getName()
sometimes returns "<anonymous>" instead of the principal's
name.
A) Why isn't the principal's name = context's principal's name?
B) Can we ensure that principal's name isn't lost?
As per the documentation, the user principal is associated with the current thread,
so why is it that when calls are made in the same thread of execution from the
web layer to the EJB layer we are losing the right principal. Btw, the Principal
is always correct in the Web layer. We do not have any RunAs options set in our
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EJB - MDB and Session and Entity - Seem to always run under same Thread

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