How to Install the JDK (Java Development Kit) on Mac OS X

Apple's Mac OS X comes with the Java Runtime Environment (JRE) already configured. However, some Java applications, especially those still in beta or alpha releases, require the full Java Development Kit (JDK).

Things You'll Need

• A computer running Mac OS X 10.5 or newer.
• An internet connection.
• A free Apple Developer Connection account.

Steps

1. Determine which Java Release is currently installed.
   
   
   • Open the Java Preferences application.
   • In the first row with the On checkbox is marked, note the value for the Version column. The part before the first '-' (hyphen) is the java.version for the next step.
   • Go to Apple Technical Note TN2110 and locate your java.version in the tables. Note the corresponding value in the Java Release column.
2. Download the JDK.
   • Go to Apple Developer Downloads and click Java in the Downloads menu on the right side of the page.
   • Find the Developer Package that matches your version of OS X and Java for Mac Update number.
   • Click the link under Download Name to download the JDK disk image.
3. Install the JDK
   • Once the download is complete, locate the the disk image file with Finder.
   • Double-click the disk image to mount it.
   • In the Finder window for the disk image, double-click the package file.
   • The Installer application will guide you through the rest of the installation.
   
   

Tips

• If you haven't done so recently, run Software Update before the first step.
• You can register for an Apple Developer account without signing up for one of the paid Apple Developer Programs at http://developer.apple.com/programs/register/
• Easily find the Java Preferences application with Spotlight by typing "java" in the search box.
• Quickly search for text within a web page with the ⌘-F (command-F) keyboard shortcut.

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