Debugging the init() method in a Java servlet
From what I know about how a Tomcat server works, is that if you have a Java servlet in your web application, the init() method is called whenever the server starts up.
In that case, how can I debug the init() method? Putting a break point clearly doesn't work, and for some reason System.out.println statements also do not yield any output on my server console.
I have checked that the correct web app ( .war ) is deployed and it extracts correctly in the webapps folder of my Tomcat server.
It seems to me like your deployment descriptor servlet declaration doesn't have an load-on-startup value bigger than 0. If you have omitted that element, the Servlet will only be initialized when the container deems that it should handle a request. Until then, the init method is not called.
By providing the load-on-startup value, like so
<servlet>
<servlet-name>servlet</servlet-name>
<servlet-class>com.example.YourServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
You are telling the container to initialize the Servlet right away, therefore invoking your init method on startup, rather than when the first request for that servlet arrives.
It is not correct, the init() method is not called when server startsup. It is called only once and it is called during the FIRST CALL TO YOUR SERVLET to which the same init() method belongs.
As there is one init() for each Serlvet, init() for respective servlet is called when you call the servlet for first time. ie After container loads the servlet and instantiates it then init() method is called.
Either do,
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