You can change Web application archives (WAR files) on application servers without having to stop the server and start it again.
There are several changes that you can make to WAR files without stopping the server and starting it again. You can use the update wizard of the administrative console to make the changes without having to stop and restart the server. This article describes how to make the following changes by manipulating a WAR file on the server where the application is deployed:
Place the changed JSP file directly in the application_root/module_name directory or the appropriate subdirectory. The change will be automatically detected and the JSP will be recompiled and reloaded.
Hot deployment
Not applicable
Dynamic reloading
Yes
Adding a new JSP file to an existing application
Place the new JSP file directly in the application_root/module_name directory or the appropriate subdirectory. The new file will be automatically detected and compiled on the first request to the page.
Hot deployment
Yes
Dynamic reloading
Yes
Changing an existing servlet class (editing and recompiling)
Place the new version of the servlet .class file directly in the application_root/module_name/WEB-INF/classes directory.
If the .class file is part of a Jar file, you can place the new version of the Jar file directly in application_root/module_name/WEB-INF/lib.
In either case, the change will be detected, the Web application will be shut down and reinitialized, picking up the new class.
If automatic reloading is enabled, you do not need to take further action. Automatic reloading will detect the change.
Hot deployment
Not applicable
Dynamic reloading
Yes
Changing a dependent class of an existing servlet class
Place the new version of the dependent .class file directly in the application_root/module_name/WEB-INF/classes directory.
If the .class file is part of a Jar file, you can place the new version of the Jar file directly in application_root/module_name/WEB-INF/lib.
In either case, the change will be detected, the Web application will be shut down and reinitialized, picking up the new class.
If automatic reloading is enabled, you do not need to take further action. Automatic reloading will detect the change.
Hot deployment
Not applicable
Dynamic reloading
Yes
Adding a new servlet using the Invoker (Serve Servlets by class name) facility or adding a dependent class to an existing application
Place the new .class file directly in the application_root/module_name/WEB-INF/classes directory.
If the .class file is part of a Jar file, you can place the new version of the Jar file directly in application_root/module_name/WEB-INF/lib.
In either case, the change will be detected, the Web application will be shut down and reinitialized, picking up the new class.
This case is treated the same as changing an existing class. The difference is that adding the servlet or class does not immediately cause the Web application to reload because the class has never been loaded before. The class simply becomes available for execution.
If automatic reloading is enabled, you do not need to take further action. Automatic reloading will detect the change.
Hot deployment
Yes
Dynamic reloading
Not applicable
Adding a new servlet, including a new definition of the servlet in the web.xml deployment descriptor for the application
Place the new .class file directly in the application_root/module_name/WEB-INF/classes directory.
If the ".class" file is part of a Jar file, you can place the new version of the Jar file directly in application_root/module_name/WEB-INF/lib.
You can edit the web.xml file in place or copy it into the application_root/module_name/WEB-INF/classes directory.
The new .class file will not trigger a reloading of the application.
Edit the extension settings as needed. You can change all of the extension settings.
The only warning is if you set the reloadInterval property to zero (0)
or the reloadEnabled property to false, the application no longer automatically detects changes to class files. Both of these changes disable the automatic reloading function. The only way to re-enable automatic reloading is to change the appropriate property and restart the application. See other task descriptions in this file for information on restarting an application.
Hot deployment
Not applicable
Dynamic reloading
Yes
Changing the ibm-web-bnd.xmi file of a WAR file
Edit the bindings as needed. You can change all of the values but ensure that the entities you are binding to are present in the configuration of the server.