Ejb calling ejb, how many threads?

A few of questions regarding the way WLS threads EJBs:
1. It seems straightforward if I deploy a WLS "application" that's composed of
a single EJB. I suppose that the app runs as a thread within the WLS JVM and "pooling"
also makes sense.
2. But what about an "application" that's composed of 2 EJBs, one calling the
methods of the other. Is each EJB ran in its on thread? It seems like they would
have to be in order to "pool" them or does the "pooling" affect the entire "application",
i.e. you don't pool the individual beans but the entire app?
3. How is all this affected by using local interfaces for the EJB-to-EJB method
calls?How does this affect pooling and threading within WLS?
Thanks.

Hi Jack,
"Jack Ottofaro" <[email protected]> wrote in message
news:[email protected]..
A few of questions regarding the way WLS threads EJBs:
1. It seems straightforward if I deploy a WLS "application" that'scomposed of
a single EJB. I suppose that the app runs as a thread within the WLS JVMand "pooling"
also makes sense.It just seems because you have the question number two :)
2. But what about an "application" that's composed of 2 EJBs, one callingthe
methods of the other. Is each EJB ran in its on thread? It seems like theywould
Actual EJB code runs within a thread that first began
processing of the request. So you may have two cases.
First, if the bean is colocated (belongs to the same jar
or ear) with the caller, by default it will be a local call
and the bean will run within a caller thread. Second,
if it's remote call, it will run within "its own" thread.
have to be in order to "pool" them or does the "pooling" affect the entire"application",
i.e. you don't pool the individual beans but the entire app?I'm not sure I understood the question.
3. How is all this affected by using local interfaces for the EJB-to-EJBmethod
calls?How does this affect pooling and threading within WLS?Local interfaces buys nothing but mess. By default all calls to
the beans residing in the same application , even if they are
declared as EJBObjects, are optimized to be local so that
parameters are passed by reference and are not subjects of
serialization.
Hope this helps.
Regards,
Slava Imeshev

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I understand that one thread belongs to the caller of the start()
& at the same time there is another thread belonging to the instances of each thread (thread1, thread2, thread 3 etc.)
1public class ThreadTester {
2   public static void main( String args[] )
3   {
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5
6      thread1 = new PrintThread( "thread1" );
7      thread2 = new PrintThread( "thread2" );
8      thread3 = new PrintThread( "thread3" );
9      thread4 = new PrintThread( "thread4" );
10
11      System.err.println( "\nStarting threads" );
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13      thread1.start();
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16      thread4.start();
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18      System.err.println( "Threads started\n" );
19   }
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13..............1.........1.......2
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there is only one thread belonging to the caller at line 13(plus the thread it creates).
at the start of line 14, the previous callers thread is dead & now a new thread is created that belongs to the caller on line 14... etc.

well, i realize at the end there would be 4 threads but im trying to get my head around this explanation in the book:
"A program launches a threads executioin by calling the threads start method, which in turn call the run method. After start launches the thread, start returns to tis caller immediately. The caller then executes concurrently with the lauched thread." there fore if i have 2 concurrent processes, are there 2 threads running????
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Last edited by natostanco (2012-04-28 10:16:13)

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How many reocrds update in call transaction method and session method

The flat file having the 10 records but the flat file having the 5 th record is error so in session method how many records will update and in call transaction how many records will update.
can you provide with detailed information like in synchrnous mode and asynchronous mode
Regards
reddy

hi,
session method :up to 4 records will be updated as it is in synchronus mode.
Call transaction method : except 5 th all 9 records will be updated as it is assyncronous method.
Regards
sandeep Reddy

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Is there a way to find out all the running/active/blocked/unknown threads in a JVM?
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I use jdk1.4 on Red Hat Linux.
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suri

HI,
Is there a way to find out all the
running/active/blocked/unknown threads in a JVM?
Doesn't matter if it is through code or some external
command.
I use jdk1.4 on Red Hat Linux.
Thanks and Regards
suri'jdb' tool lets you know how many threads exist in an application. try these command
compile your program with '-g' option.
jdb <classname>
stop at <classname>:<line no of main(){}>
run
threads
You can notice four threads. But I guess in linux, it might show lots of verbose with thread ID, If possible pls post the result for us to see.

How many will update in BDC.

In bdc flat file having 10 records.but 5th record having error.in call transaction how many records will update.
can any body explain on MODE wise means if put the mode A how many records will update.mode E ,mode N. and explainn fore ground and baground.

Hello ,
Mode
A Display all
E Display errors only
N No display
If u set the mode as 'A'.
U will see all the screens when the processing is being done.
If u set the mode as 'E'
U will see the screen only if the screen has errors or else the processing will take place internally.
If u set the mode as 'N'
U will not see any screen irrespective of error or success.
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Now coming to ur example :-
If u set the the update process as one of the below :
update> : Update mode:
S Synchronous
A Asynchronous
L Local update
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If u set as S
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If u set as 'L'
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Regards,
Deepu.K

Ejb calling ejb, how many threads?

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