Provide a property to change loadOnStartup for DispatcherServlet.

[izeye]

It would be nice to provide a property to change loadOnStartup for DispatcherServlet.

In Spring Boot, loadOnStartup for DispatcherServlet is -1.

Is there any reason to use -1 as default value?

[philwebb]

-1 is the default, same as javax.servlet.ServletRegistration. Any specific reason why you want something else as the default?

[izeye]

@philwebb I just want to make sure

that the DispatcherServlet has been loaded before the first request.

Although -1 doesn't make any problem for me, I just thought it's more natural.

Am I wrong?

And in the Spring framework document, every example has 1 for load-on-startup as follows:

    <servlet>
        <servlet-name>example</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>

I just thought it's sort of recommendation (this could be a wrong assumption).

[philwebb]

The lifecycle with Spring Boot's embedded servlet containers is a little different to WAR based deployments. With WAR deployments, the Servlet creates the application context. With embedded containers, the application context is created first and contains the servlet container. Spring Boot should also ensure that no requests can be processed before the container is fully started.

I think the property option could be useful and it's something we can consider for 1.3.

[izeye]

@philwebb Thanks for the explanation.

[benneq]

any progress on this? i'd like to preload my dispatcher servlet, too.

[wilkinsona]

@benneq The issue's currently targeted at 1.4