The element ‘load-on-startup‘ is used to load the servlet. The ‘void init()‘ method of servlet gets executed when the server gets started. The element content of ‘load-on-startup’ is Integer.
- if the integer is negative: The container loads servlet at any time.
- if the integer is 0 or positive: The servlet marked with lower integers are loaded before servlets marked with higher integers.
How to add element load-on-startup while mapping servlet?
The load-on-startup is the sub-attribute of servlet attribute in web.xml. We do mapping of servlet in web.xml file.
In XML file
XML
<servlet> <servlet-name>servletOne</servlet-name> <servlet-class>com.gfg.ServletOne</servlet-class> <load-on-startup>0</load-on-startup> </servlet> <servlet> <servlet-name>servletTwo</servlet-name> <servlet-class>com.gfg.ServletTwo</servlet-class> <load-on-startup>1</load-on-startup> </servlet> |
ServletOne load first then ServletTwo get load.
Servlet Code
servletOne.java
Java
package com.gfg;import javax.servlet.*;import javax.servlet.http.*;import java.io.*; public class ServletOne extends HttpServlet{ public void init() { // this method will get execute // when the server get start System.out.println("ServletOne got called"); }} |
servletTwo.java
Java
package com.gfg;import javax.servlet.*;import javax.servlet.http.*;import java.io.*; public class ServletTwo extends HttpServlet{ public void init() { // this method will get execute // when the server get start System.out.println("ServletTwo got called"); }} |
Note: the above code is server-side code it will not work on online IDE (it is only for the clarification of the topic).
