How do you configure JSP in a web.xml file?

The following article demonstrates how to configure JSP in a web.xml.

In JSP (JavaServer Pages), you can configure the JSP engine by adding elements to the web.xml deployment descriptor file. The following steps describe how to configure JSP in the web.xml file.

To begin with, open the web.xml file in a text editor. For this purpose, add the following servlet declaration to define the JSP servlet.

<servlet>
    <servlet-name>jsp</servlet-name>
    <servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>
    <init-param>
        <param-name>fork</param-name>
        <param-value>false</param-value>
    </init-param>
    <init-param>
        <param-name>xpoweredBy</param-name>
        <param-value>false</param-value>
    </init-param>
    <load-on-startup>3</load-on-startup>
</servlet>

This defines a servlet named jsp that uses the JspServlet class provided by the Apache Jasper implementation of JSP. It also sets two optional parameters: fork and xpoweredBy. The fork parameter specifies whether to run the JSP servlet in a separate process or in the same process as the web server. The xpoweredBy parameter specifies whether to include an X-Powered-By header in the HTTP response.

2. After that, add the following servlet mapping declaration to map the JSP servlet to the URL pattern that identifies JSP pages.

<servlet-mapping>
    <servlet-name>jsp</servlet-name>
    <url-pattern>*.jsp</url-pattern>
</servlet-mapping>

This maps the jsp servlet to any URL that ends with the .jsp file extension, which is typically used for JSP pages.

3. Next, save the changes to the web.xml file.

Once you have added these elements to the web.xml file, the JSP engine will be configured to process JSP pages in your web application. Note that these instructions assume that you are using the Apache Jasper implementation of JSP, which is included in many popular Java web application servers such as Apache Tomcat. If you are using a different JSP engine, the exact configuration steps may differ.

Further Reading