Enabling the Invoker Servlet

The Invoker Servlet allows unconfigured servlets to be called by simply using a /servlet URL.

It is disabled by default in new Tomcat installations, and new metawerx hosting accounts, for security reasons.

To enable the Invoker Servlet, add the following to your <appName>/WEB-INF/web.xml file, between the <web-app> tags:

<servlet>
	<servlet-name>MyInvoker</servlet-name>
	<servlet-class>
		org.apache.catalina.servlets.InvokerServlet
	</servlet-class>
</servlet>

<servlet-mapping>
	<servlet-name>MyInvoker</servlet-name>
	<url-pattern>/servlet/*</url-pattern>
</servlet-mapping>

Here is a complete, minimal example of a web.xml file containing the above. If you are not familiar with web.xml at all, just save the following file as <appName>/WEB-INF/web.xml file to get started:

<?xml version="1.0" encoding="ISO-8859-1"?>

<web-app xmlns="http://java.sun.com/xml/ns/j2ee"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
	version="2.4">

	<display-name>My App</display-name>
	<description>
		My Application
	</description>

	<servlet>
		<servlet-name>MyInvoker</servlet-name>
		<servlet-class>
			org.apache.catalina.servlets.InvokerServlet
		</servlet-class>
	</servlet>

	<servlet-mapping>
		<servlet-name>MyInvoker</servlet-name>
		<url-pattern>/servlet/*</url-pattern>
	</servlet-mapping>
	
</web-app>

More Information

• How do I deploy my application on Tomcat? - support article
• Deploying an application with the Tomcat Manager - support article
• Creating your first Tomcat application - full tutorial