The classes in the servlet are good for looking through documents, familiar with the common methods of each class, and looking at some classic case code.
ServletConfig
Each project has more than one servlet, and each servlet corresponds to a Servletconfigt object. The configuration information for each servlet is encapsulated in ServletConfig, specifically the configuration content in <servlet></servlet> in Web. Xml.
You can use Httpserlet's This.getserletconfig method to get ServletConfig
ServletContext:
Each project corresponds to a servletcontext,servletcontext entity package that corresponds to the configuration information in Web. XML, which contains more content. You can use Thi.getservletconfig (). Getservletcontext () in a servlet to get ServletContext can also be obtained directly using This.getservletcontext directly () , which is also the first method of invocation.
As can be seen from the above, the range of ServletContext is larger than the range of ServletConfig.
Domain objects in a servlet
Servletcontext,httpservletrequest,httpsession.
Domain objects in JSPs (of course, jsp9 large built-in objects)
applicaltion, Httpservletrequest,httpsession,pagecontext. Application is actually ServletContext (you can directly see the JSP translated into the Java file)
Comb some of the web's general concepts