CS636 hw4 JPA, Intro Spring Boot webapps, tomcat (shared and embedded)

due Tues., Apr. 20  on Gradescope.  (Apr. 19 is a holiday)

1. Learn about JPA and Object-relational Mapping. Read Chapter 13 of Murach, and its slides, linked for the class of March 22 and 25. See JPA2 Notes for a guide to this chapter.
   1. Download and try out pizza2, the JPA version of the Pizza Project. Note that you need need to reload the databases for pizza2, because there’s a new table. See pizza2/README for how to run the project. Report on any problems.
      
   2. Set up the pizza2 project in eclipse. using "Open Project from Filesystem". Use eclipse to compare the domain packages of pizza1 and pizza2 and report on the differences, grouping similar differences. To compare two packages, select one in the Package Explorer, use control-click to select the other as well, right-click and Compare With>Each Other.
      
   3. Note that this project uses Spring beans as well as JPA. This means the *Service and *DAO objects (the singletons) are set up by Spring based on class annotations in *Service.java and *DAO.java. Report on the class annotations in these classes. Also verify that PizzaSystemConfig now no longer creates these objects.
      
   
   
2. More practice on HTTP requests. Consider the HTML on pg. 37 of Murach and here, (/data/htdocs/cs636/ch02email/web/index.html in the filesystem) slightly different but not enough to change these answers. This file resides in directory ch02email (a subdirectory of the document root) on our shared tomcat server (so its host is "localhost" when we work on pe07) at port 8080.
   
   1. What HTTP request (first line only) happens when the user (who is logged into pe07) browses to URL http://localhost:8080/ch02email/emailList, the endpoint of this servlet? What is returned by this request? Try it out with lynx. (Let me know if the shared tomcat is down. Test it by accessing its root URL localhost:8080).
   2. What HTTP request (first line only) happens when the user clicks the submit button, shown in green by lynx? Assume user input as shown on pg. 35 (joel@murach.com, Joel, Murach).
   3. What name=value pairs (known as formdata) are sent back when the user submits the form?  Where are these values in the request?
   4. What HTTP request (first line only) happens at page load to obtain the CSS for the page?
3. Try out our shared tomcat on pe07 and simple JSPs without JSTL.  Tomcat is the servlet-capable web server that we will be using to execute web applications.  We now have a shared tomcat server running on  pe07.cs.umb.edu (on port 8080) for your experimentation. Note that you need a tunnel from (say) localhost:8888 to  pe07.cs.umb.edu:8080 to access this server from your browser, similar to what you did earlier for the pizza page flow (that tomcat was running on port 9002, and is an "embedded tomcat" serving only one app).  You can look at our shared tomcat's files at /var/cs636/tomcat-8.5 in the UNIX/Linux filesystem. Its document root is /var/cs636/tomcat-8.5/webapps.
   
   1. First browse to http://pe07.cs.umb.edu:8080 (http://localhost:8888 from home) to see the "root" page. You should see a picture of a tomcat and some text about the Apache Tomcat project.  Also links, including to some JSP examples of interest, but unfortunately written in old JSP. 
      
   2. Then browse to http://pe07.cs.umb.edu:8080/basicjsp/date_el.jsp, and see the current date printed out, as discussed in class Monday, Mar. 10. Then browse to http://pe07.cs.umb.edu:8080/cs636/index.html to see my little html page.  This file index.html is situated at file path /var/cs636/tomcat-8.5/webapps/cs636/index.html in the Linux filesystem.  You are welcome to look at it there.  Report on what this page says. Follow its link and see another little page. The first page was served by the shared tomcat. What server served the second page?
4. Tomcat and simple JSPs with JSTL (where we see <c: constructs)
   
   1. Study tomcat's  /basicjstl directory (filesystem directory /var/cs636/tomcat-8.5/webapps/basicjstl), including subdirectories. You will see count.jsp and guess.jsp. Note that because these JSPs use JSTL for loop constructs (<c:foreach) and conditional code (<c:if), they need a WEB-INF directory with a lib directory containing the jstl and standard jars. We didn't need these for the basicjsp files because they only used EL and standard JSP tags like jsp:useBean. See Chapter 6. Display the ls -lR output (recursive directory listing) for the basicjstl directory. Run count.jsp and guess.jsp and report on what you see, and what HTML is sent to your browser. 
   2. In tomcat's /basicjstl_broken, find a count.jsp that has been broken by removing the / from </c:forEach>. Browse to it and report on the error.  Explain how it points to the bad line.
5. Embedded Tomcat at home serving the ch05emailS project
   
   1. Download the ch05emailS project to your home system, build it with "mvn package", and use "run” or "run.sh" to run it using port 9000 on your home system. This is a Spring project, but unlike pizza2, has no singletons to set up as Spring beans. We are using Spring Boot here for its embedded tomcat capability. Browse to http://localhost:9000/emailList to see the form shown on pg.61. Fill in the form and see the second page, shown on pg. 135 or pg. 137. Figure out which one it is and why and explain this in your homework paper.  The document root is (as usual for a Spring Boot webapp) at src/main/webapp. When done, bring the app down by using control-C for Windows or Linux or Command-C for Mac on the run command.
   2. Open the project in eclipse and run it by selecting WebApplication.java in Package Explorer, right-click, Run As>Java Application. Report success or problems.
   3. Show that this tomcat can do other JSPs as well by copying webapps/basicjsp/date_el.jsp from our shared tomcat to webapp/basicjsp/date_el.jsp in this tomcat's area. What URL is needed to execute it?
   4. Add code to the servlet and thanks.jsp to display the action string involved in the request. Explain the edits needed for this change.
6. Running ch05emailS on pe07.  Transfer the result of problem 5 from your home system to your own cs636 directory on pe07, and follow the README directions to run it on one of your assigned TCP ports. Try accessing it with lynx and also be setting up a tunnel from your home system. Report success or problems. Leave it at cs636/ch05emailS.
7. Trying out pizza3. Download pizza3.zip, unzip it, and start an eclipse project for it. 
   1. Run SystemTest using Oracle and runJarByProfile and note the command used (by you and by the shell program) and success or problems.
   2. Then run the web version of the project using Oracle, and order a pizza. What URL was used to request the display of the order form?
   3. Run SystemTest via its servlet by browsing to its URL. Read SysTestServlet.java to find out the URL to use.  Report the URL and success or problems. Where did you find the output of SystemTest in this case?