macOS - How to install Java 17

Question

Could someone please let me know the steps to install Java on a Mac.

I did brew install java

I get this

Warning: openjdk 17.0.1 is already installed and up-to-date.
To reinstall 17.0.1, run:
  brew reinstall openjdk

If I do java -version, I get this.

openjdk version "13.0.8" 2021-07-20

If I have navigate to /Library/Java, I have 2 empty directories.

Where is java 17 installed??

Answer 1

Java doesn't mind if you install multiple versions. This is often required; java is not backwards compatible (it tries to change little, but e.g. the java8 to java9 transition broke a ton of stuff, much of it needless and much of it not reasonably expectable or fixable by libraries and apps, so a bunch of java apps and libraries only run on java8 - just an example).

So, yes, you have installed JDK17. Also, yes, if you just run java without specifying which one you want, you so happen to get java13 here.

To see all installed javas, you can run:

/usr/libexec/java_home -V

to 'override', you can use something like (depends on which shell you're using on your mac):

export JAVA_HOME=`/usr/libexec/java_home -v 17`

(the backticks mean: Run this then take the output of it and treat that as the 'value' of the expression. here, assign it to the JAVA_HOME env var. -v 17 requests a path to java 17. The -V option lists all and is meant for your eyeballs, not for scripts. The -v option is mostly for scripting, and that's how we're using it here).

JAVA_HOME decides which java is used by some things, but the java you get when you just type java is /usr/bin/java, and that executable is actually just a wrapper that picks a java to run from amongst all installed versions. It uses JAVA_HOME to decide which java to actually run. There are wrappers for all the common commands (javac, too). You can always run e.g. which javac to see what that actually runs; you probably see /usr/bin/javac. Everything in /usr/bin is one of these wrapper thingies that looks at JAVA_HOME and then runs the binary it finds there.

Answer 2

In 2022, you can use just brew

brew install openjdk

and maybe you need to update PATH env:

export PATH="/usr/local/opt/openjdk/bin:$PATH"

…and for the future give a try to sdkman, is better than brew

curl -s "https://get.sdkman.io" | bash

then open a new shell and try list to see what you could install ;-)

sdk list java 

At time of writing you could use:

sdk install java 17.0.1-tem

Answer 3

To used the version installed by homebrew rather than the one installed by the OS you can get detailed information from homebrew by typing

brew info java

Currently it states

For the system Java wrappers to find this JDK, symlink it with sudo ln -sfn /opt/homebrew/opt/openjdk/libexec/openjdk.jdk /Library/Java/JavaVirtualMachines/openjdk.jdk

openjdk is keg-only, which means it was not symlinked into /opt/homebrew, because macOS provides similar software and installing this software in parallel can cause all kinds of trouble. If you need to have openjdk first in your PATH, run: echo 'export PATH="/opt/homebrew/opt/openjdk/bin:$PATH"' >> ~/.zshrc For compilers to find openjdk you may need to set: export CPPFLAGS="-I/opt/homebrew/opt/openjdk/include"

Answer 4

Steps to install

You asked:

let me know the steps to install Java on a Mac.

1. Download an installer free-of-cost from vendors such as Adoptium, Azul Systems, Bellsoft, Amazon, Oracle, Microsoft, SAP, and others.
2. Run installer app.
3. Quit the installer app when done.
4. Verify installation by typing on a command-line in Terminal.app:
   java --version
5. Delete installer app that you downloaded.
6. Configure your IDE to use that new Java implementation you installed.

Java location

You asked:

Where is java 17 installed??

/Library/Java/JavaVirtualMachines/

In the Finder, choose Go > Go to Folder, and paste /Library/Java/JavaVirtualMachines/.

Note that this is not the Library folder within your home folder. We are not referring to /Users/your_user_name/Library/…. We are referring to the root Library folder that applies across all the user accounts on this Mac.

You said:

I did brew install java

No need for the Homebrew package manager. If you already enjoy using the brew tool, proceed. But if new to Homebrew, skip it if your only goal is to install Java. Just use an installer for Java as you would for many Mac apps.

JavaFX

You added a tag for javafx.

Be aware that for JavaFX, you have two options:

• Include the necessary OpenJFX libraries within your development project and within your final app, or …
• Use a JDK that includes the JavaFX/OpenJFX libraries.

At least two vendors provide JDK installers that include the JavaFX/OpenJFX libraries:

• Azul Systems (ZuluFX)
• Bellsoft (LibericaFX)

Answer 5

I think that answers here are not fully out of topic, but from my point of view, my case is exactly the same as that of the author. I had already installed java 8, 11, and 13. All of them resides at:

/Library/Java/JavaVirtualMachines/

Nevertheless when I tried to find the path of JDK 17 it resides:

/usr/local/Cellar/openjdk

I use Mac OS Big Sur and the JDK was installed with homebrew

Answer 6

This answer is specifically if you use Intellij on a Mac

Within IntelliJ, you can use the IDE to add new JDKs of selected versions from common vendors. Instructions for this are here:

• Setup the project JDK

When setting up the JDK, you can either:

1. Select a pre-existing JDK which has been registered with the IDE OR
2. Use the Add JDK option to add a new JDK which you previously downloaded and installed using the method outlined in Basil's answer OR
3. Use the Download JDK option to choose a vendor and version of the JDK that the IDE will automatically download, install and make available for selection.
   • The JDKs installed by Idea will be located in the same location as outlined in Basil's answer for a manual install /Library/Java/JavaVirtualMachines/.

One common issue is that the version of the JDK registered for the project differs from the default version used in the terminal. This can sometimes mean that the app works when run in Idea, then fails when run in the terminal (or, at least that it is executed against a version of the JDK you didn't expect).

To select the version of the JDK to run in the terminal, configure the Java home setting as outlined in rzwitserloot's answer.

export JAVA_HOME=`/usr/libexec/java_home -v 17`

Also, some tools such as the openjfx maven plugin will not use the java version selected in Idea when executing a call to a JDK tool like jlink, but will instead have their own mechanism for finding a JDK to use (e.g. look at JAVA_HOME or use the Maven toolchains plugin). So it is always good to check the JAVA_HOME variable and ensure that it is set to a reasonable value, both for terminal execution and for effective use of Java development tools that may rely on it.

Answer 7

The following method installs Java without the need for any additional tools or package managers.

Go to https://jdk.java.net/17/ and download the latest macOS archive.

This is either for x64 (Intel CPU) or for AArch64 (Apple Silicon / M1 CPU).

Then, open a Terminal, and extract the downloaded archive to the system path for Java virtual machines:

cd Downloads
tar xzf openjdk-17.0.2_macos-aarch64_bin.tar.gz -C /Library/Java/JavaVirtualMachines