HOW TO Run NetBeans 8.2 on Mac OS X with JDK 9

On September 21, 2017 the 9.0 release of the Java Development Kit (JDK) became available to the general public.  However, NetBeans 8.2 does not work properly running on Mac OS X High Sierra using the 9.01 release of the JDK.  The product installs without a problem; however, when you start the Integrated Development Environment (IDE) it does not operate properly.  For example, selecting either the "New File..." or "New Project..." menu items from the "File" menu does nothing.  The status panel in the bottom right corner of the IDE indicates there is a single notification.  When you click on it, you get a screen similar to the one shown below.

The solution is to run NetBeans with JDK 8.  The first step in the process is to make sure you are no longer running NetBeans, so select the "Quit NetBeans" menu item  from the "NetBeans" menu.  

The next step involves heading over to Oracle's Java SE download page.

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

Left-click on the "Downloads" tab and then navigate down to the section entitled "Java SE 8".  Below is a photograph of how that web page looks for the 151/152 updates of the Java 8 platform.

Left-click on the "Download" button for the Java 8 JDK and follow the on-screen instructions to complete the process of downloading the latest version.  After completing the JDK installation process, left-click on the "Finder" icon in the Dock, left-click on the "Go" menu and then left-click on the "Go To Folder..." menu item.  When presented with the "Go to the folder" panel, enter "/Library/Java/JavaVirtualMachines" in the fields as shown in the figure below.

Left-click on the "Go" button and you'll be presented with a window similar to the one shown in the figure below.

Record the name of the JDK 8 folder.  For this example, it is "jdk1.8.0_152.jdk".

Go to the "Applications" folder in Finder.

Left-double-click on the "NetBeans" folder.

Right-click on the "NetBeans 8.2.app" icon and then left-click on the "Show Package Contents" menu item.

Left double-click on the "Contents" folder.  Left double-click on the "Resources" folder.  Left double-click on the "NetBeans" folder.  Left double-click on the "etc" folder.

Open the "netbeans.conf" file with Text Edit.  This will open the configuration file in the editor allowing you to make changes.   Locate the following line in the configuration file.

#netbeans_jdkhome="/path/to/jdk"

Remove the hash tag at the beginning of the line and replace the "/path/to/jdk" section of the line with the path to where JDK8 is installed on your machine.  For our example scenario, the line in the configuration file appears as follows.

netbeans_jdkhome="/Library/Java/JavaVirtualMachines/jdk1.8.0_152.jdk/Contents/Home"

Save the changes to the configuration file.

After following this process, you should be able to run NetBeans 8.2 on your Mac without any problems.

References
morteza08. "New project and New file do not operate." NetBeans Forums, 24 Sept. 2017, https://forums.netbeans.org/topic68000.html.

Oracle. "Java SE Development Kit 8 Downloads." Oracle.com, 17 Oct. 2017, http://www.oracle.com/technetwork/java/javase/overview/index.html.

Oracle. “Oracle Announces Java SE 9 and Java EE 8.” Oracle.com, Oracle, 21 Sept. 2017, www.oracle.com/corporate/pressrelease/java-se-9-and-ee-8-092117.html.