I do not want java on my system. But sometimes it is needed. These are notes how to make it available without having it permanentaly enabled.

❯ brew search jdk
==> Formulae
openjdk ✔                openjdk@11 ✔             openjdk@17 ✔             openjdk@21               openjdk@8                jd                       mdk                      cdk

==> Casks
adoptopenjdk                 graalvm-jdk@17               microsoft-openjdk            microsoft-openjdk@21         oracle-jdk-javadoc@21        sapmachine-jdk               semeru-jdk-open@17
gama-jdk                     graalvm-jdk@21               microsoft-openjdk@11         oracle-jdk                   oracle-jdk@17                semeru-jdk-open              semeru-jdk-open@21
graalvm-jdk                  jdk-mission-control          microsoft-openjdk@17         oracle-jdk-javadoc           oracle-jdk@21                semeru-jdk-open@11           semeru-jdk-open@8

❯ brew info openjdk@11     
==> openjdk@11: stable 11.0.26 (bottled) [keg-only]
Development kit for the Java programming language
https://openjdk.java.net/
Installed
/opt/homebrew/Cellar/openjdk@11/11.0.26 (667 files, 295.4MB) *
  Poured from bottle using the formulae.brew.sh API on 2025-02-09 at 10:33:59
From: https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/o/[email protected]
License: GPL-2.0-only
==> Dependencies
Build: autoconf ✘, pkgconf ✘
Required: freetype ✔, giflib ✔, harfbuzz ✔, jpeg-turbo ✔, libpng ✔, little-cms2 ✔
==> Caveats
For the system Java wrappers to find this JDK, symlink it with
  sudo ln -sfn /opt/homebrew/opt/openjdk@11/libexec/openjdk.jdk /Library/Java/JavaVirtualMachines/openjdk-11.jdk

openjdk@11 is keg-only, which means it was not symlinked into /opt/homebrew,
because this is an alternate version of another formula.

If you need to have openjdk@11 first in your PATH, run:
  echo 'export PATH="/opt/homebrew/opt/openjdk@11/bin:$PATH"' >> /Users/vit/.zsh/.zshrc

For compilers to find openjdk@11 you may need to set:
  export CPPFLAGS="-I/opt/homebrew/opt/openjdk@11/include"
==> Analytics
install: 25,058 (30 days), 78,407 (90 days), 316,068 (365 days)
install-on-request: 22,023 (30 days), 66,256 (90 days), 253,801 (365 days)
build-error: 28 (30 days)

The key is the line in the output above

export PATH="/opt/homebrew/opt/openjdk@11/bin:$PATH"