Defines a servlet alias for later mapping.

Attribute	Description
servlet-name	The servlet's name (alias)
servlet-class	The servlet's class (defaults to servlet-name)
init-param	Initialization parameters
load-on-startup	Initializes the servlet when the server starts.
run-at	Times to execute the servlet automatically

The following example defines a servlet alias 'hello'

<web-app id='/'> <servlet-mapping url-pattern='/hello.html' servlet-name='hello'/> <servlet servlet-name='hello' servlet-class='test.HelloWorld'> <init-param title='Hello, World'/> </servlet> <servlet servlet-name='cron' servlet-class='test.DailyChores'> <run-at>3:00</run-at> </servlet> </web-app>

Alias of the servlet

Class of the servlet The CLASSPATH for servlets includes the WEB-INF/classes directory and all jars in the WEB-INF/lib directory.

Initializes servlet variables. servlet-param defines initial values for getServletConfig().getInitParameter("foo"). The full servlet 2.2 syntax is supported and allows a simple shortcut

<web-app id='/'> <servlet servlet-name='test.HelloWorld'> <init-param foo='bar'/> <init-param> <param-name>baz</param-name> <param-value>value</param-value> </init-param> </servlet> </web-app>

If present, starts the servlet when the server starts.

<web-app id='/'> <servlet servlet-name='hello' servlet-class='test.HelloWorld'> <load-on-startup/> </servlet> </web-app>

If present, calls the servlet's service() method at the specified times. <run-at> lets servlet writers execute periodic tasks without worrying about creating a new Thread.

The value is a list of 24-hour times when the servlet should be automatically executed. To run the servlet every 6 hours, you could use

<servlet servlet-name='test.HelloWorld'> <run-at>0:00, 6:00, 12:00, 18:00</run-at> </servlet>

If the hour is omitted, the servlet runs every hour at the specified minute. To run the server every 15 minutes, you could use:

<servlet servlet-name='test.HelloWorld'> <run-at>:00, :15, :30, :45</run-at> </servlet>