Re: Two instances of servlet gets created
In my case if the request comes from within the same context, it works fine and does not creates two instances. But if I have another application deployed in different context and sending a request to my servlet, then, there is new instance of servlet gets created. I tried with one example, creating link in HTML file to call my servlet. And tried to call my servlet by copying this file into both the contexts and then clicking this link a href=../servlet/wf.Handler.user?wfuser_id=TimedTesting_1Dummy workflow TimedWfTesting_1/a wf.Handler.user is the name of my servlet. The result remain same. For the different context, another instance gets created for my servlet. Is this the behaviors of servlets ? How can I control it for only one instance creation ? - Original Message - From: Gavin, Rick [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Thursday, January 02, 2003 7:37 PM Subject: RE: Two instances of servlet gets created I have also been seeing this, I think since I have upgraded from 4.1.12. I have a startup servlet that creates a singleton object i use for system properties, and it calls the createInstance of the singleton twice at startup now. Rick -Original Message- From: Mohit Garg [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 02, 2003 3:52 AM To: Tomcat Users List Subject: Two instances of servlet gets created I have startup servlet for which one instance is created as soon as my tomcat starts. But on the first request to the servlet there is another instance created. i.e Another time init() is called for the servlet. -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
RE: Two instances of servlet gets created
-Original Message- From: Mohit Garg [mailto:[EMAIL PROTECTED]] Sent: Friday, January 03, 2003 5:42 AM To: Tomcat Users List Subject: Re: Two instances of servlet gets created In my case if the request comes from within the same context, it works fine and does not creates two instances. This is correct. But if I have another application deployed in different context and sending a request to my servlet, then, there is new instance of servlet gets created. This is also correct. Each context is loading your servlet into its own classloader, so it doesn't know about the other web apps(context)'s classes. You can move your common functionality(singleton,etc) into its own class, which you can put in /common/lib (or /common/classes) where it will only be loaded once and shared for all web apps. you may want to review the classloading document: http://jakarta.apache.org/tomcat/tomcat-4.1-doc/class-loader-howto.html Charlie I tried with one example, creating link in HTML file to call my servlet. And tried to call my servlet by copying this file into both the contexts and then clicking this link a href=../servlet/wf.Handler.user?wfuser_id=TimedTesting_1Dum my workflow TimedWfTesting_1/a wf.Handler.user is the name of my servlet. The result remain same. For the different context, another instance gets created for my servlet. Is this the behaviors of servlets ? How can I control it for only one instance creation ? - Original Message - From: Gavin, Rick [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Thursday, January 02, 2003 7:37 PM Subject: RE: Two instances of servlet gets created I have also been seeing this, I think since I have upgraded from 4.1.12. I have a startup servlet that creates a singleton object i use for system properties, and it calls the createInstance of the singleton twice at startup now. Rick -Original Message- From: Mohit Garg [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 02, 2003 3:52 AM To: Tomcat Users List Subject: Two instances of servlet gets created I have startup servlet for which one instance is created as soon as my tomcat starts. But on the first request to the servlet there is another instance created. i.e Another time init() is called for the servlet. -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
Re: Two instances of servlet gets created
New instances of any servlet will be created for as many times as the servlet is named differently. For instance, all these refer to the same servlet, but each will be a separate instance servlet servlet-nameMyServletName/servlet-name servlet-classcom.mypackage.MyServlet/servlet-class /servlet servlet-mapping servlet-nameMyServletName/servlet-name url-pattern/mymapping/url-pattern /servlet-mapping http://localhost:8080/mycontext/mymapping http://localhost:8080/mycontext/servlet/MyServletName http://localhost:8080/mycontext/servlet/com.mypackage.MyServlet What is at issue is the invoker servlet which is mapped to /servlet/* in Tomcat's conf/web.xml. It will create these separate servlet instances. If you don't like this behavior, then disabled the invoker servletwhich is disabled by default in recent releases for security reasons. Jake At 04:11 PM 1/3/2003 +0530, you wrote: In my case if the request comes from within the same context, it works fine and does not creates two instances. But if I have another application deployed in different context and sending a request to my servlet, then, there is new instance of servlet gets created. I tried with one example, creating link in HTML file to call my servlet. And tried to call my servlet by copying this file into both the contexts and then clicking this link a href=../servlet/wf.Handler.user?wfuser_id=TimedTesting_1Dummy workflow TimedWfTesting_1/a wf.Handler.user is the name of my servlet. The result remain same. For the different context, another instance gets created for my servlet. Is this the behaviors of servlets ? How can I control it for only one instance creation ? - Original Message - From: Gavin, Rick [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Thursday, January 02, 2003 7:37 PM Subject: RE: Two instances of servlet gets created I have also been seeing this, I think since I have upgraded from 4.1.12. I have a startup servlet that creates a singleton object i use for system properties, and it calls the createInstance of the singleton twice at startup now. Rick -Original Message- From: Mohit Garg [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 02, 2003 3:52 AM To: Tomcat Users List Subject: Two instances of servlet gets created I have startup servlet for which one instance is created as soon as my tomcat starts. But on the first request to the servlet there is another instance created. i.e Another time init() is called for the servlet. -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
RE: Two instances of servlet gets created
Charlie is right. In the response I gave to this thread, I was assuming your were talking about servlets in the same context. Sorry, didn't read carefully. Anyway, my comments still apply when talking about as single context. Jake At 12:03 PM 1/3/2003 -0500, you wrote: -Original Message- From: Mohit Garg [mailto:[EMAIL PROTECTED]] Sent: Friday, January 03, 2003 5:42 AM To: Tomcat Users List Subject: Re: Two instances of servlet gets created In my case if the request comes from within the same context, it works fine and does not creates two instances. This is correct. But if I have another application deployed in different context and sending a request to my servlet, then, there is new instance of servlet gets created. This is also correct. Each context is loading your servlet into its own classloader, so it doesn't know about the other web apps(context)'s classes. You can move your common functionality(singleton,etc) into its own class, which you can put in /common/lib (or /common/classes) where it will only be loaded once and shared for all web apps. you may want to review the classloading document: http://jakarta.apache.org/tomcat/tomcat-4.1-doc/class-loader-howto.html Charlie I tried with one example, creating link in HTML file to call my servlet. And tried to call my servlet by copying this file into both the contexts and then clicking this link a href=../servlet/wf.Handler.user?wfuser_id=TimedTesting_1Dum my workflow TimedWfTesting_1/a wf.Handler.user is the name of my servlet. The result remain same. For the different context, another instance gets created for my servlet. Is this the behaviors of servlets ? How can I control it for only one instance creation ? - Original Message - From: Gavin, Rick [EMAIL PROTECTED] To: Tomcat Users List [EMAIL PROTECTED] Sent: Thursday, January 02, 2003 7:37 PM Subject: RE: Two instances of servlet gets created I have also been seeing this, I think since I have upgraded from 4.1.12. I have a startup servlet that creates a singleton object i use for system properties, and it calls the createInstance of the singleton twice at startup now. Rick -Original Message- From: Mohit Garg [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 02, 2003 3:52 AM To: Tomcat Users List Subject: Two instances of servlet gets created I have startup servlet for which one instance is created as soon as my tomcat starts. But on the first request to the servlet there is another instance created. i.e Another time init() is called for the servlet. -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
Two instances of servlet gets created
I have startup servlet for which one instance is created as soon as my tomcat starts. But on the first request to the servlet there is another instance created. i.e Another time init() is called for the servlet. -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
Re: Two instances of servlet gets created
Hi, do you call your servlet by the pattern defined in web.xml or by the full path with invoker servlet? I once read, that using the invoker servlet means creating a new instance of your servlet. Maybe that's what causes the second init(). Hope this helps Andreas On 2 Jan 2003 at 17:22, Mohit Garg wrote: I have startup servlet for which one instance is created as soon as my tomcat starts. But on the first request to the servlet there is another instance created. i.e Another time init() is called for the servlet. -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
RE: Two instances of servlet gets created
I have also been seeing this, I think since I have upgraded from 4.1.12. I have a startup servlet that creates a singleton object i use for system properties, and it calls the createInstance of the singleton twice at startup now. Rick -Original Message- From: Mohit Garg [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 02, 2003 3:52 AM To: Tomcat Users List Subject: Two instances of servlet gets created I have startup servlet for which one instance is created as soon as my tomcat starts. But on the first request to the servlet there is another instance created. i.e Another time init() is called for the servlet. -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED] -- To unsubscribe, e-mail: mailto:[EMAIL PROTECTED] For additional commands, e-mail: mailto:[EMAIL PROTECTED]
