Using Java SE on macOS Catalina


Changes introduced with macOS 10.15 (Catalina) cause certain Java applications to behave incorrectly. Therefore, we cannot certify any JDK version on macOS 10.15 yet. If you still want to install and test the JDK or JRE on macOS 10.15, then this document covers what you will experience as you install the JDK or JRE.

Eventually (as of January 2020), you will only be able to install and run Mac software distributed outside the Mac App store on macOS 10.15 systems that are notarized by Apple. With macOS 10.15, Apple introduced new application security checks, which are used by Gatekeeper to verify the contents of distributed software. When you install or run software for the first time, Gatekeeper verifies that the software has been notarized. See Notarizing Your App Before Distribution.

However, as of now, you can install and run non-notarized software on macOS 10.15 systems by modifying your security preferences. The following steps show you how to install a non-notarized JDK or JRE.

Note: These steps use the JDK 8u231 macOS installer as an example. These steps apply equally to all other JDK and JRE releases.

Installing the JDK Using a .dmg File

1. Double-click on the .dmg file to begin the installation. The system verifies the .dmg file, then opens a Finder window with the icon of an open box (package) and the name of the .pkg file.

2. Double-click the package icon to start the installation app. A window appears with a status bar with text similar to the following:

Verifying "JDK 8 Update 231.pkg"...

 

Then, a window appears with text similar to the following:

"JDK 8 Update 231.pkg" can't be opened because Apple cannot check it for malicious software.
This software needs to be updated. Contact the developer for more information.

 

Click OK.

3. Open System Preferences, click Security & Privacy, then click the General tab. In the section Allow apps downloaded from:, the following text appears:

"JDK 8 Update 231.pkg" was blocked from use because it is not from an identified developer.

 

Click the Open Anyway button.

4. A window appears with text similar to the following:

"JDK 8 Update 231.pkg" can't be opened because Apple cannot check it for malicious software.
This software needs to be updated. Contact the developer for more information.

 

Click the Open button.

5. A window appears with the following text:

Installer is trying to install new software. Enter your password to allow this.

 

Enter your user name and password, then click the Install Software button.

Installing the JDK from a File Archive

You don't have to modify your security preferences if you install the JDK from a .tar.gz file archive, in particular, a prebuilt OpenJDK package. However, the system may warn you the first time you run a Java command-line tool.

Running a Java Command-Line Tool for the First Time

When you run a command-line tool for the first time (such as java), depending on which app (such as Safari or Firefox) you used to download the installer, a window may appear with text similar to the following:

"jdk1.8.0_231.jdk" is an app created by Safari. Are you sure you want to open it?

 

Click the Open button.

Depending on the folder in which you installed the JDK or JRE, another window may also appear with text similar to the following:

"java" would like to access files in your Downloads folder.

 

Click the OK button.