Re: concurrency in struts
So you mean to say that there should not be any class variable used? But even though there are more then one thread executing execute method then? There is a possibility that for one thread 2 parameters will be filled and for other thread remaing 3. So all parameters are having different values from two different users while it stores for only one user. I appologize if I am going to very basic! -Jignesh On Monday 10 May 2004 18:36, Daniel Perry wrote: Each request to the same action subclass uses the same object. The method is called passing all necessary parameters to it. Therefore you should not use any class variables, only local variables. Ie, a MyAction class is created once, and for each request to it, it's method is called: public ActionForward execute( ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) This object is retained throughout application lifecycle, and reused for each request. Daniel. -Original Message- From: Jignesh Patel [mailto:[EMAIL PROTECTED] Sent: 10 May 2004 14:04 To: Struts Users Mailing List; Geeta Ramani Subject: Re: concurrency in struts Hi Geeta, Can you elaborate more? -Jignesh On Monday 10 May 2004 18:18, Geeta Ramani wrote: Jignesh: The execute method of the Action class includes (among others) as params the request, response objects of each user.. That I believe is the key..:) Regards, Geeta -Original Message- From: Jignesh Patel [mailto:[EMAIL PROTECTED] Sent: Monday, May 10, 2004 8:54 AM To: Struts Users Mailing List Subject: concurrency in struts On Monday 10 May 2004 17:21, Jignesh Patel wrote: I am just wondering, how concurrent request will be handled by single Action class. Because for many form objects(as there are thousands of browser running with jsp forms) and there is only one action class. -- Jignesh Patel Project Leader - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] -- Jignesh Patel Project Leader Bang Software Technolgy Pvt. Ltd. (E) [EMAIL PROTECTED] (T) 091 484 3942132 B-4, Smart Business Centre, Infopark, SDF IT Building, Kusumagiri P.O.,Kakkanad, Kochi - 682030, Kerala, India. Information contained in this transmission to the named addressee, including any attachments thereto, should be considered the proprietary and confidential information of the sender. As a condition for viewing the information, the sender agrees to keep the information confidential, to refrain from disclosing the information, directly or indirectly, and to refrain from any actions that would constitute or facilitate unauthorized access to the information without express permission from the sender. The recipient also acknowledges and agrees to respect sender's intellectual property rights in and to the information. If the recipient of this transmission is not the named addressee, the recipient should immediately notify the sender and destroy the information transmitted without making any copy or distribution thereof. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] -- Jignesh Patel Project Leader Bang Software Technolgy Pvt. Ltd. (E) [EMAIL PROTECTED] (T) 091 484 3942132 B-4, Smart Business Centre, Infopark, SDF IT Building, Kusumagiri P.O.,Kakkanad, Kochi - 682030, Kerala, India. Information contained in this transmission to the named addressee, including any attachments thereto, should be considered the proprietary and confidential information of the sender. As a condition for viewing the information, the sender agrees to keep the information confidential, to refrain from disclosing the information, directly or indirectly, and to refrain from any actions that would constitute or facilitate unauthorized access to the information without express permission from the sender. The recipient also acknowledges and agrees to respect sender's intellectual property rights in and to the information. If the recipient of this transmission is not the named addressee, the recipient should immediately notify the sender and destroy the information transmitted without making any copy or distribution thereof. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL
Re: concurrency in struts
There are two concepts you have to understand: thread-safe and reentrant. A method is reentrant, if many threads can enter the method as the same time without conflicting. For that you only have to act on parameters and local variables. Threads only share the data- and the code-segment of an application. Every thread gets his own stack-segment, where all local variables and the parameters will be push onto. If you act in the execute-method only on the parameters and on local variables you are thread safe. If you will join shared ressources as database connections ... you have to take care, that such ressources are either pooled or the access is sychronized. So the message is: In the execute Method don't use global variables but only local variables. This and the parameters are pushed on your stack, that is only in your thread visible. Hope it helps Manfred Wolff Jignesh Patel wrote: Riyad, But does this methods are synchronized? Otherwise if two threads execute at the same time they can access the method at the same time. And result will be big mess. -Jignesh On Monday 10 May 2004 18:29, Riyad Kalla wrote: This question is actually what made me sign up to this mailing list... the answer is that there is no implicit concurrency. All your work/variables in Actions should be method-scoped and not use ANY class variables because of this. My specific questions was that I wanted to use a class variable ActionErrors so any of my methods (DispatchAction) could add errors without initializing a new ActionError instance, and return it. But this is incorrect and can/will introduce problems. So there is no concurrency in Struts. Jignesh Patel wrote: On Monday 10 May 2004 17:21, Jignesh Patel wrote: I am just wondering, how concurrent request will be handled by single Action class. Because for many form objects(as there are thousands of browser running with jsp forms) and there is only one action class. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
concurrency in struts
I am just wondering, how concurrent request will be handled by single Action class. Because for many form objects(as there are thousands of clients) there are only one action class. -- Jignesh Patel Project Leader Bang Software Technolgy Pvt. Ltd. (E) [EMAIL PROTECTED] (T) 091 484 3942132 B-4, Smart Business Centre, Infopark, SDF IT Building, Kusumagiri P.O.,Kakkanad, Kochi - 682030, Kerala, India. Information contained in this transmission to the named addressee, including any attachments thereto, should be considered the proprietary and confidential information of the sender. As a condition for viewing the information, the sender agrees to keep the information confidential, to refrain from disclosing the information, directly or indirectly, and to refrain from any actions that would constitute or facilitate unauthorized access to the information without express permission from the sender. The recipient also acknowledges and agrees to respect sender's intellectual property rights in and to the information. If the recipient of this transmission is not the named addressee, the recipient should immediately notify the sender and destroy the information transmitted without making any copy or distribution thereof. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: concurrency in struts
Hello, I think, but i hope that somebody could answer better, that the servlet container will instantiate a new Servlet, and accompanying Action classes, if this is needed. As far as i know, in J2EE, this is the servlet container who is responsible for forking new threads for the clients on-demand. Could somebody confirm (or infirm) that this is right ? Best regards, Ludo Jignesh Patel wrote: On Monday 10 May 2004 17:21, Jignesh Patel wrote: I am just wondering, how concurrent request will be handled by single Action class. Because for many form objects(as there are thousands of browser running with jsp forms) and there is only one action class. -- Ludovic Maître Factory Productions | Tél: (33) 04 93 07 08 00 149, avenue des mimosas | Fax: (33) 04 93 07 04 02 06700 Saint-Laurent-du-Var (France) | Web: http://www.factory.fr - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: concurrency in struts
Yes, somebody did indeed answer better.. Please see Manfred Wolff's earlier response in this thread. :) -Original Message- From: Ludovic Maitre [mailto:[EMAIL PROTECTED] Sent: Monday, May 10, 2004 9:08 AM To: Struts Users Mailing List Subject: Re: concurrency in struts Hello, I think, but i hope that somebody could answer better, that the servlet container will instantiate a new Servlet, and accompanying Action classes, if this is needed. As far as i know, in J2EE, this is the servlet container who is responsible for forking new threads for the clients on-demand. Could somebody confirm (or infirm) that this is right ? Best regards, Ludo Jignesh Patel wrote: On Monday 10 May 2004 17:21, Jignesh Patel wrote: I am just wondering, how concurrent request will be handled by single Action class. Because for many form objects(as there are thousands of browser running with jsp forms) and there is only one action class. -- Ludovic Maître Factory Productions | Tél: (33) 04 93 07 08 00 149, avenue des mimosas | Fax: (33) 04 93 07 04 02 06700 Saint-Laurent-du-Var (France) | Web: http://www.factory.fr - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: concurrency in struts
Hi Geeta, Can you elaborate more? -Jignesh On Monday 10 May 2004 18:18, Geeta Ramani wrote: Jignesh: The execute method of the Action class includes (among others) as params the request, response objects of each user.. That I believe is the key..:) Regards, Geeta -Original Message- From: Jignesh Patel [mailto:[EMAIL PROTECTED] Sent: Monday, May 10, 2004 8:54 AM To: Struts Users Mailing List Subject: concurrency in struts On Monday 10 May 2004 17:21, Jignesh Patel wrote: I am just wondering, how concurrent request will be handled by single Action class. Because for many form objects(as there are thousands of browser running with jsp forms) and there is only one action class. -- Jignesh Patel Project Leader - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] -- Jignesh Patel Project Leader Bang Software Technolgy Pvt. Ltd. (E) [EMAIL PROTECTED] (T) 091 484 3942132 B-4, Smart Business Centre, Infopark, SDF IT Building, Kusumagiri P.O.,Kakkanad, Kochi - 682030, Kerala, India. Information contained in this transmission to the named addressee, including any attachments thereto, should be considered the proprietary and confidential information of the sender. As a condition for viewing the information, the sender agrees to keep the information confidential, to refrain from disclosing the information, directly or indirectly, and to refrain from any actions that would constitute or facilitate unauthorized access to the information without express permission from the sender. The recipient also acknowledges and agrees to respect sender's intellectual property rights in and to the information. If the recipient of this transmission is not the named addressee, the recipient should immediately notify the sender and destroy the information transmitted without making any copy or distribution thereof. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: concurrency in struts
Riyad, But does this methods are synchronized? Otherwise if two threads execute at the same time they can access the method at the same time. And result will be big mess. -Jignesh On Monday 10 May 2004 18:29, Riyad Kalla wrote: This question is actually what made me sign up to this mailing list... the answer is that there is no implicit concurrency. All your work/variables in Actions should be method-scoped and not use ANY class variables because of this. My specific questions was that I wanted to use a class variable ActionErrors so any of my methods (DispatchAction) could add errors without initializing a new ActionError instance, and return it. But this is incorrect and can/will introduce problems. So there is no concurrency in Struts. Jignesh Patel wrote: On Monday 10 May 2004 17:21, Jignesh Patel wrote: I am just wondering, how concurrent request will be handled by single Action class. Because for many form objects(as there are thousands of browser running with jsp forms) and there is only one action class. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] -- Jignesh Patel Project Leader Bang Software Technolgy Pvt. Ltd. (E) [EMAIL PROTECTED] (T) 091 484 3942132 B-4, Smart Business Centre, Infopark, SDF IT Building, Kusumagiri P.O.,Kakkanad, Kochi - 682030, Kerala, India. Information contained in this transmission to the named addressee, including any attachments thereto, should be considered the proprietary and confidential information of the sender. As a condition for viewing the information, the sender agrees to keep the information confidential, to refrain from disclosing the information, directly or indirectly, and to refrain from any actions that would constitute or facilitate unauthorized access to the information without express permission from the sender. The recipient also acknowledges and agrees to respect sender's intellectual property rights in and to the information. If the recipient of this transmission is not the named addressee, the recipient should immediately notify the sender and destroy the information transmitted without making any copy or distribution thereof. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: concurrency in struts
Each request to the same action subclass uses the same object. The method is called passing all necessary parameters to it. Therefore you should not use any class variables, only local variables. Ie, a MyAction class is created once, and for each request to it, it's method is called: public ActionForward execute( ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) This object is retained throughout application lifecycle, and reused for each request. Daniel. -Original Message- From: Jignesh Patel [mailto:[EMAIL PROTECTED] Sent: 10 May 2004 14:04 To: Struts Users Mailing List; Geeta Ramani Subject: Re: concurrency in struts Hi Geeta, Can you elaborate more? -Jignesh On Monday 10 May 2004 18:18, Geeta Ramani wrote: Jignesh: The execute method of the Action class includes (among others) as params the request, response objects of each user.. That I believe is the key..:) Regards, Geeta -Original Message- From: Jignesh Patel [mailto:[EMAIL PROTECTED] Sent: Monday, May 10, 2004 8:54 AM To: Struts Users Mailing List Subject: concurrency in struts On Monday 10 May 2004 17:21, Jignesh Patel wrote: I am just wondering, how concurrent request will be handled by single Action class. Because for many form objects(as there are thousands of browser running with jsp forms) and there is only one action class. -- Jignesh Patel Project Leader - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] -- Jignesh Patel Project Leader Bang Software Technolgy Pvt. Ltd. (E) [EMAIL PROTECTED] (T) 091 484 3942132 B-4, Smart Business Centre, Infopark, SDF IT Building, Kusumagiri P.O.,Kakkanad, Kochi - 682030, Kerala, India. Information contained in this transmission to the named addressee, including any attachments thereto, should be considered the proprietary and confidential information of the sender. As a condition for viewing the information, the sender agrees to keep the information confidential, to refrain from disclosing the information, directly or indirectly, and to refrain from any actions that would constitute or facilitate unauthorized access to the information without express permission from the sender. The recipient also acknowledges and agrees to respect sender's intellectual property rights in and to the information. If the recipient of this transmission is not the named addressee, the recipient should immediately notify the sender and destroy the information transmitted without making any copy or distribution thereof. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
