Downloading and Installing the Java Development Kit

The Java Development Kit (JDK) can be downloaded from the following web address:

http://www.oracle.com/technetwork/java/javase/downloads/index.html

The Java download tab includes links to download the JDK or the Java Runtime Environment (JRE). Follow the JDK link because clicking the JRE link gets you only the JRE, not the complete JDK.

The JDK download comes in two versions: an online version that requires an active Internet connection to install the JDK, and an offline version that lets you download the JDK installation file to your computer and install it later.

I recommend using the offline version. That way, you can reinstall the JDK if you need to without having to download it again.

The exact size of the offline version depends on the platform, but most versions are between 50MB and 60MB, so that means that your download will take a few hours if you don’t have a high-speed Internet connection. With a broadband cable, DSL, or T1 connection, though, the download takes less than five minutes.

After you download the JDK file, install it by running its executable file. The procedure varies slightly depending on your operating system, but basically, you just run the JDK installation program file after you download it, as follows:

On a Windows system, open the folder in which you saved the installation program and double-click the installation program’s icon.

On a Linux or Solaris system, use console commands to change to the directory to which you downloaded the file and then run the program.

After you start the installation program, it prompts you for any information that it needs to install the JDK properly, such as which features you want to install and what folder you want to install the JDK in. You can safely choose the default answer for each option.

Note: If you’re an Apple Mac user, you don’t have to download and install the Java JDK. Apple pre-installs the JDK on Mac computers.