Installing Java and BlueJ on Linux

As you may have guessed from my screencasts, I use Linux. It is a great operating system that offers distinct advantages for experienced users, but it is also suitable for adventurous beginners. Personally, I use Lubuntu, but any version of Linux will do for this course.

Open a terminal window. On many Linux versions, you get one with Control+Alt+T. Or try searching for Terminal in the system menu or the search bar. You need to know how to copy/paste information into a terminal window. Copy the usual way with Control+C. To paste, use Shift-Insert. And whenever you enter a command in the terminal, hit the Enter key so that the command is executed. For example, if I ask you to run ls, you type ls and Enter.

Now follow these steps:

• Visit the Java download site. Click on “Accept License Agreement”. Download either the Linux x86 or Linux x64 version, depending on whether you have a 32- or 64-bit version of Linux. (Don't know which one you have? Run uname -m in the terminal. If you get something ending in _64, such as x86_64, you have 64 bit and choose the x64 version. Otherwise, you have 32 bit and choose the x86 version.) Pick the .tar.gz version, not the .rpm version (even if you use Fedora Linux). Pay attention to the name of the downloaded file—you'll need it in the next step.
• Uncompress the downloaded file in your home directory. In the terminal window, run these commands:

  tar xvfz Downloads/jdk-7u21-linux-i586.tar.gz          
  

  except, that you should use the actual filename that you just downloaded.
• Now go to the BlueJ download site. Download the version described as “for all other versions”, with extension .jar (even if you have Debian or Ubuntu).
• In a terminal window, type

  jdk1.7.0_21/bin/java -jar Downloads/bluej-309.jar
  

  However, if you downloaded a different minor version of Java than 21, or a different version of BlueJ than 3.09, adjust the numbers. You should now get a BlueJ installer window.

  

  Accept all defaults.

• In the terminal window, run

  bluej/bluej

  You should get a BlueJ opening screen. Leave it opened.

  

• Finally, download the lesson 1 zip file. In the terminal window, run

  unzip Downloads/lesson1.zip

  Then, in BlueJ, select Project → Open from the menu and navigate to the lesson1 directory inside your home directory, then select the hello project. When you open it, it should look like this.

  

If you got this all to work, congratulations. If not, please post a question on the forum.