Tips for creating a course workspace

Version 2023

In our course, we will make use of three main software applications:

Unfortunately, these three softwares, especially the JDK, are subject to continuous updates, which in addition to fixing bugs and adding features can sometimes introduce new bugs and incompatibilities with the examples shown during the lactures that are based on a specific combination of versions, tested and “certified” before the course begins.

To minimize problems, I recommend you install the same versions indicated at the beginning of the course (even if they are not the latest available). Even better, I suggest you to create a “private” workspace dedicated to the course tools that is influenced as little as possible by the actual software set-up of the machine you will be working on. This is very useful especially if on your machine you have already installed other versions of the mentioned softwares. The procedure is as follows.

The software versions for the academic year 2023 / 2024 are indicated in the Software section.

Warning: Tomcat 9 and Tomcat 10 (or higher) cannot run the same web applications: while Tomcat 9 uses the JEE 8 Web, Tomcat 10 uses the Jakarta EE 9 Web, which requires to manually modify the packages of many classes used by the web applications. In the Web Engineering course we will show how to adapt applications to run on both versions.

Warning: some Maven plugins normally used by Netbeans are not compatible with the latest JDK versions. During the course we will show how to edit the standard projects generated by the IDE to make them work again. In any case, all projects published online are fixed and, being based on Maven, can be used as a starting point for your applications, also on other IDEs.

Note: If you are sufficiently skilled in using another IDE, you can use the one that you already have available instead of Netbeans, but obviously in that case you will have to manage by yourself the configuration required by your IDE to deploy a web application.

Download and Install the Software

  1. Create a new folder in your user home (e.g., Documents for Windows users). Below we will indicate this folder with “<D >” (where <D> is an absolute path, for example C:\Users\foo\Documents\workspace or /home/foo/workspace).
  2. In the <D> folder, create three sub-folders named <D>/nb_userdir, <D>/nb_cachedir and <D>/tomcat_base
  3. Download the zip archives (no installers!) of the JDK, Netbeans and Tomcat with the recommended versions. You may have to download them from “archive” pages such as https://jdk.java.net/archive/, https://netbeans.apache.org/download/archive/ (or https://netbeans.apache.org/download) and < https://tomcat.apache.org/whichversion.html>.
  4. Expand archives in the <D> folder. You will get three folders, for example (real name will depend on versions) <D>/jdk-JV, <D>/netbeans-NV and <D>/apache-tomcat-TV.
  5. In the folder where Netbeans was expanded, in our example <D>/netbeans-NV, you will find the file etc/netbeans.conf. Within this file, modify the following keys as indicated.
    Note that the JDK path must be defined based on the folder it is in was actually expanded to point 4. If necessary, delete the comment (#) before the lines containing these keys to enable them. Remember to save the netbeans.conf file when you are done making changes.
    • netbeans_default_userdir = “<D>/nb_userdir”
    • netbeans_default_cachedir = “<D>/nb_cachedir”
    • netbeans_jdkhome = “<D>/jdk-JV”

First Launch of the IDE

  1. At this point, you can run Netbeans using the launchers present in the bin folder. If you work on Windows, use the executable “netbeans64.exe” if you downloaded a 64bit JDK, otherwise use the “netbeans.exe” executable. On Unix and Mac systems, use the shell script “netbeans”.
    If the IDE asks you to import the configuration already present on your machine (maybe from an older version) answer no.

  2. Select the Tools > Java Platforms menu item and verify that the JDK you have installed is present in the list and marked as “Default” (the relative “Platform folder” must be the one specified in the netbeans_jdkhome key, and therefore located inside <D>).

Tomcat configuration

At this point you can proceed and connect Netbeans to Tomcat.

  1. Select the Tools > Servers menu item and then the “Add Server…” button.
  2. In the next wizard select “Apache Tomcat or TomEE” and specify as “Server location” the folder <D>/apache-tomcat-TV (also here the actual name will change as the version changes).
  3. Optionally, check the “use private configuration folder” box and enter the <D>/tomcat_base folder as “Catalina base”. This this is not necessary if you have unzipped Tomcat in your home directory, while it is required if you have installed it in other locations on your machine (for example in the Windows Program Files folder).
  4. Enter simple credentials in the “Username” and “Password” boxes (the IDE may ask you for them several times in the future) and make sure that the The “Create user if if does not exist” box is checked.
  5. Finish the process. At this point you should see the server just installed in the “Servers” list of the dialog box. Check that in the “Platform” tab for the new server the “Java Platform” is the same default JDK used by the IDE.

Configuration Test

To test the new configuration,

  1. First try to start Tomcat by clicking with the right mouse button on the corresponding sub-entry of the “Servers” node shown in the tab/box “Services” of the IDE and selecting “Start”. If you you are prompted for credentials for the “Tomcat Manager Application”, type the ones defined in the previous section. Hopefully, you will see the server logs shown by the IDE listing a number of information lines that will end with a line like “Server startup in […] milliseconds”. This will confirm that the server started successfully.
  2. Create a simple web application, add a servlet to it and try to run it. If the web browser opens showing the defaulw application welcome page (index), try to access the URL of the servlet you created. If the servlet also answers with its own default message, the environment is configured correctly. Note: you might having to configure which browser to open automatically by selecting it from Tools > Options menu item.