Appendix F. web.xml reference

The web.xml file is one step up from the main configuration directory. It is located in the <basedir>/www/WEB-INF directory. This configuration file contains settings that are related to the web application only. Most settings in this file should not be changed because they are vital for the functionality of BASE.


If an error occurs during a page request, the execution is forwarded to the specified JSP which will display information about the error.

<context-param>: max-url-length

This setting is here to resolve a potential problem with too long generated URL:s. This may happen when BASE needs to open a pop-up window and a user has selected a lot of items (e.g., several hundred). Typically the generated URL contains all selected ID:s. Some web servers have limitations on the length of an URL (e.g., Apache has a default max of 8190 bytes). If the generated URL is longer that this setting, BASE will re-write the request to make the URL shorter and supply the rest of the parameters as part of a POST request instead. This functionality can disabled by setting this value to 0. For more information see

<servlet>: BASE

A servlet that starts BASE when Tomcat starts, and stops BASE when Tomcat stops. Do not modify.

<servlet>: view/download

File view/download servlet. It is possible to change the default MIME type for use with files of unknown type.

<servlet>: spotimage

Servlet for displaying spot images. Do not modify.

<servlet>: plotter

Servlet for the plot tool in the analysis section. You may specify max and default values for the width and height for the generated images. The supported image formats are "png" and "jpeg".

<servlet>: AxisServlet/AxisRESTServlet

Servlet handling web service requests. If you are not planning to access your BASE installation using web services these servlets may be disabled.

<servlet>: ExtensionsServlet

Servlet for handling startup/shutdown of the extensions system as well as requests to extension servlets. Do not modify. Do not disable even if extensions are not used.

<servlet>: xjsp

Experimental servlet for compiling *.xjsp files used by extensions. The servlet redirects the compilation of *.xjsp files to a compiler that includes the extension supplied JAR file(s) in the class path.

<servlet>: compile

Experimental servlet for compiling all JSP files. This is mostly useful for developers who want to make sure that no compilation error exists in any JSP file. Can also be used to pre-compile all JSP files to avoid delays during browsing. This servlet is disabled by default.

<filter>: characterEncoding

A filter that sets the character encoding for the JSP generated HTML. We recommend leaving this at the default UTF-8 encoding, this default should work with most language in all modern browsers.