Tomcat: reloading modified servlets?

hi
in tomcat it's possible to configure a servlet context to automaticaly reload if the servlet was rebuild. i know how to do that and i works.
what i want to change is the reation time of tomcat. it sometimes takes quite a long time till tomcat realizes that a servlet has changed and reloads it. I think that mechnism is quite simple, kind of a thread that looks for a new modifed date of the servlet file and reloads or not and goes to sleep again for a amount of time. My question: is there a possibility to configurate that parameter that handels the sleep time?
thanx for your help!

If you get hold of the source (this is from v4.0.4)
Look in org.apache.cataline.loader.StandardLoader.java
you will see at line 164 that this value has a hard coded default of 15 (seconds).
There is a public void setCheckInterval(int checkInterval) but I'm not sure where you can configure this to be set - I can't find any classes which call it.
It might be possible to access the loader from a servlet run at start up with an init() method that sets a new value.
HH

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Do we need to restart the Tomcat server each time when we modify servlets?

Hi Friends,
Do we need to restart the Tomcat server each time when we modify servlets. Or is there any otherway to achieve the functionalitly?
Thanks and Regards,
JG

JamesGeorge wrote:
Hi kajbj,
Java guys are mostly using TOMCAT,so for me it seems to be the best place.That's not correct. Most people who are writing stuff for the web might be using Tomcat, but there are lots and lots of Java applications that aren't for the web.
Is there any other reason behind your question.Yes, this forum is named "New to Java" and Tomcat questions shouldn't be asked here, even if people knows the answer to you question. You will probably get better and more detailed answers in a Tomcat forum. All othe guys there are actually using Tomcat, and they know the small differences between the different versions, and how they behave on different operating systems. They do also know if you need to make configurations changes, and where you should make them.
So in future, please ask questions in a forum that is specific to the product that you are using.

Modified Servlet not visible

Hi,
I created a servlet & then ran it , it worked fine. After that I modified it so that it should display a different message on browser but its displaying the previous staff. Strangely even if I delete the servlet & then try to access it using a URL , I will see the same stuff which present in the servlet before starting the tomcat. However if I stop tomcat & hen restart it again I will see the modified servlet or error message if servlet not available. How can I get around with this prob of viewing the modified servlet without restarting the tomcat.
Zulfi.

add reloadable attribute to the Context entry in conf/server.xml. by default it does not include reloadable, change
    
    <Context path="" docBase="ROOT" debug="0"/>to
    
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See:
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How can i avoid restarting tomcat server when servlet is modified?

please advice me that how can i avoid restarting the tomcat server, whenever a servlet file is modified in my application. is their any way ?

No probs. Here's how I do things...
1. Install tomcat as normal (e.g. I install to C:\Apps\jakarta-tomcat-5.5.4)
2. Create a webapps directory in your eclipse project with the following directory structure
MyEclipseProject
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8. In the 'conf' directory I create a server.xml file used to configure Tomcat (you can copy the one from your <TOMCAT_HOME>/conf/server.xml).
After copying the file change appBase attribute in the host element to be the full path to the webapps directory. You can also change the HTTP and HTTPS ports if you wish
9. Download and install the Tomcat Launcher plugin from Sysdeo.
10. In Eclipse's Preferences menu you will see a new entry for Tomcat. Click this then
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b. Set your Tomcat Home
c. Set "Context declaration mode" to server.xml
d. Set the configuration file to the full path to your server.xml file created in step 8
On the "Advanced " sub page select all relevant projects to add to the Tomcat classpath
On the "JVM Settings" page add all the jars in your WEB-INF lib directory to the class path
On the "Source Path" page select all relevant projects
Now if you start Tomcat using the Tomcat icon, you will be able to remote debug your application. If you change web.xml (or any other file in your context.xml watched resources) it will automatically reload. Any changes to JSPs will automatically be picked up (providing your tell your browser not to use the page in cache - e.g. CTRL+F5 in IE)
There are some limitations that I'm still working on however. Primarily that I haven't included the Tomcat Manager application in my webapps directory, so Sysdeo cannot perform a reload. This means that if I change a source file, and eclipse auotmatically rebuilds, Tomcat doesn't pick up the change unless I either change a watched resource file (e.g. web.xml) or stop and restart Tomcat.
There's no reason why this can't be fixed, I just haven't got round to it yet.
I'm sure there are lots of other (probably better) ways of achieving the same thing. This was the first method I tried and it worked, so I stuck with it. I'm not a Tomcat config guru and I'm sure other forum users could provide some improvements should they wish.
Post if you get into trouble, however I won't be able to respond until next week.
Cheers,
Steve

Restart tomcat at every servlet modify?

Hi,
I'm using tomcat 5.5 and working on some servlets, but when I execute a servlet (http://localhost/my_servlet)
and then I modify and recompile it, I have to shutdown and restart tomcat to see the new version on work.
Is this normal? Can I avoid this?
Thanx

Well, I have solved the problem editing contex.wml file modifying the line:
<Context>into the line:
<Context reloadable="true">Now it works even if refresh time is not so low...
Thanx to all.
P.S.
Adding the line
<DefaultContext reloadable="true"/>into server.xml file I don't have obtained any result.

Regarding TOmcat Restart evertime servlet is modified

Hi,
Myself Ashwin MIttal, using Tomcat on the Linux and Windows OS. Hey I am developing servlet and when I deploy servlet each time. I have to restart the Tomcat ....
Is there anyway to solve the problem means There is no need to restart the Tomcat when eber serlvet is modified..
Regards,
Ashwin Mittal.

In the context, type reloadable="true"yup, this is a better option.But you want to only do this on your developement machine. reloadable contexts take up a lot of resources, every x amount of time, the server has to check the classpath directories for modified time. Even if you don't make changes, this takes up resources. So once you move from development to deployment you want to turn this off...

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I don't think there's anything to prohibit you from deploying servlets in ROOT, but webapps that have pages and servlets that work together should be in their own context. That's what you did when you created the directory under webapps. I think it's the right way to deploy web apps. Even better, learn how to create and deploy WAR files:
http://access1.sun.com/techarticles/simple.WAR.html
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Hi,
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i've just recently installed Dialect Payment client onto my server and is using Java to correspond with the server. I can run the diagnostic test run perfectly fine but when I have compiled the form and the app, I keep getting the error:
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I haven't worked with this vendor product, but here are some ideas you might find useful:
It appears is a configuration problem when using the vendor software (but they already told you that, didn't they!!!).
I say the above because these lines in your printout are from vendor supplied objects (that you didn't create):
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PaymentClient.util.PCConfigurationService.getConfiguration(PCConfigurationService.java:72)
I suggest creating a brand new project with the simplist use of the above vendor project and get it to work.
You can use the vendor's (on line) documentation to do this. Deploy it in production to ensure there are no deployment issues. Work closely with one of
your fellow employees (more than one pair of eyes can pick up stuff that you miss). Next, look at what features of the vendor software the originial project uses and what features the sample project uses. Try to implement a subset of functionality of the orginial project into the sample project and get that to work. Implement the next feature, test, etc. Do small experiments at a time so you can easily isolate what doesnt work.
If none of the above works for you, try contacting the manufacturer or thier support web site. If none of the above works, look into using a compeditors product.

Tomcat: reloading modified servlets?

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