Using Java SE on macOS Catalina

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.

JDK 14 is the first release that complies with the new macOS 10.15 hardening and notarization requirements. If you want to install and test earlier versions of the JDK or JRE on macOS 10.15, this document explains some expect warnings and how to proceed.

As of the time when this article was written you can still 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:

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:

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:

Click the OK button.