Installing Java and BlueJ

Programming often requires a Software Development Kit (SDK) that provides a set of tools to help you write programs. The Java SDK, abbreviated "JDK," needs to be installed on your machine for this course, along with an Integrated Development Environment (IDE) that will give us even more tools. So, you need to make sure that both the JDK 8 and BlueJ IDE are installed on your computer.

1. Installing the BlueJ IDE
   We'll be using an Integrated Development Environment for most of our year. Download and install BlueJ 5.4.4. for your machine/operating system.
2. Installing the Java SDK
   Although BlueJ installs its own version of the JDK, we're going to download and install a separate copy as well, if you don't already have it installed on your computer.
   1. "Do I already have the Java SDK (JDK) installed on my computer?"
      If so, you won't need to proceed any further. You can determine whether or not the JDK is installed on your computer by opening up a Terminal (if using OS X or Linux), or a Command Prompt (if using Windows), and issuing this command:

      $ javac -version
      javac 1.6.0_65

      If a version number of 1.8... is listed, then you have the JDK 8 already installed, but if you get an error message (see Windows example below) or a version lower than 1.8—in the result above I have only 1.6—you'll need to do the install as described next.

   C:\Users\rw> javac -version
   'javac' is not recognized as an internal or external command,
   operatable program or batch file.

   2. Installing the Java SDK
      1. Find, download, and install the correct JDK for your computer
         Java's SDK, or JDK, can be downloaded from Oracle. Choose the correct download for your machine and operating system.
         
         Here you see the current download page for Java 8, which is what we'll be using in this course. After accepting the license agreement you'll need to select the OS X 64-bit download (all current model Macs are 64-bit), or Windows x64 for a 64-bit Windows machine (all newer models).
         
         Notice we're installing the JDK, and not the JRE.
         
         
      2. Once you've selected the version you wish to download you'll be taken to a download page.
      3. You'll need to sign up for a free Oracle account in order to download the software.
      4. Confirm that you've correctly installed the JDK 8 by trying to invoke the javac -version command as shown above.

If you have any questions, please don't hesitate to contact the instructor.