In this lesson we will learn about the basic technology
underneath the Java/Jakarta EE: servlets.
Servlets are classes that are instantiated and run on the application
server and process HTTP requests at particular URL(s) and produce a response.
We will create a couple of servlet applications.
first watch this without doing anything: https://www.youtube.com/watch?v=AJxBg90HM4s
(small detail: we will not use JSP and we do not need to change run configurations)
- register for EDU account on jetbrains
- download latest intellij idea ultimate
- download glassfish 6.2.3 Jakarta EE Platform
- run intellij and create new project
java enterprise
select project template Web application
application server - select new...
and enter path to glassfish/bin folder
group - enter some package name
artifact - enter name of project, i.e. firstservlet
project jdk: either select folder with JDK or download
NEXT
select Version: Jakarta EE 9
keep Servlet 5.0.0 checked
in project browser locate src/main/webapp/index.jsp
and delete it
instead, insert new html file in webapp folder (with right click)
and paste the following contents in it:
(we do not want to use JSP, we do not need and it
is an outdated technology)
First servlet
First Servlet
Hello Servlet
now you can press the green PLAY button to deploy the app and automatically open a browser, click the link to send request
to the servlet
study all the various files and folders and their contents
in your automatically created project
make some trivial modifications to see they apply in the application
read this chapter:
http://dai.fmph.uniba.sk/courses/java2/jsp/jsp/kap3.pdf
(ask for pass on ms teams)
optional - you can also read chapter2 here:
http://dai.fmph.uniba.sk/courses/java2/glassfish/j7.pdf
(same credentials)
now task for you:
- create a simple calculator servlet, inputs are entered
in the form and retrieved as servlet parameters
- add a two total sums of calculated results
across all requests 1) within the same user session, 2) globally
use the servlet attributes for this purpose
next:
- see homework in LIST
more recommended reading:
- https://www.developer.com/java/data/exploring-the-servlet-4-0-apis-of-java-ee-8/
- https://portswigger.net/daily-swig/http-3-everything-you-need-to-know-about-the-next-generation-web-protocol
for absolute gurus:
- https://jakarta.ee/specifications/servlet/5.0/jakarta-servlet-spec-5.0.html