はじめに
- JavaはOracleの方針変更によって，短期的にメジャーリリースをする方針となっている．世の中では，Java6アプリをやっとJava8に入れ通うかと言っていたのに，Java9,Java10と矢継ぎ早にリリースされて，さらにそれがサポート終了を迎える．Java11,Java12の時代が到来しているけれど，色々なものが追いついてない．
- 今回は，インストール要件にJava8となっているアプリケーションを動かすために，2019/06/25現在でJava8をインストールを実施してみる．
HomeBrewで提供されているJavaを確認する
$ brew search java🆑
==> Formulae
app-engine-java google-java-format javarepl jslint4java libreadline-java
==> Casks
charles-applejava java java6 oracle-jdk-javadoc
eclipse-java java-beta netbeans-java-ee yourkit-java-profiler
eclipse-javascript java11 netbeans-java-se
$
$ brew info java🆑
Error: No available formula with the name "java"
Found a cask named "java" instead.
java: 12.0.1,69cfe15208a647278a19ef0990eea691
https://www.oracle.com/technetwork/java/javase/
Not installed
From: https://github.com/Homebrew/homebrew-cask/blob/master/Casks/java.rb
==> Name
OpenJDK Java Development Kit
==> Artifacts
jdk-12.0.1.jdk -> /Library/Java/JavaVirtualMachines/openjdk-12.0.1.jdk (Generic Artifact)
$
- 無印のJavaは，Oracleの最新のバージョン12.0.1だった．
JDKを調べる
- OracleやOpenJDKはそのサポートポリシーから古いバージョンはサポートしないので，他のベンダの提供するJDKを探してみる．
- まずは，HomeBrewで現在利用できるJDKを確認．
$ brew search jdk
==> Casks
adoptopenjdk adoptopenjdk8 oracle-jdk oracle-jdk-javadoc sapmachine-jdk
$
- 名前からadoptopenjdk8は期待できそう．詳細を確認．
$ brew info adoptopenjdk8🆑
Error: No available formula with the name "adoptopenjdk8"
Found a cask named "adoptopenjdk8" instead.
adoptopenjdk8: 8,212:b03
https://adoptopenjdk.net/
Not installed
From: https://github.com/Homebrew/homebrew-cask-versions/blob/master/Casks/adoptopenjdk8.rb
==> Name
AdoptOpenJDK 8
==> Artifacts
OpenJDK8U-jdk_x64_mac_hotspot_8u212b03.pkg (Pkg)
$
- バージョン８のJavaが提供されている模様．
- もう１つ気になるSAPが提供しているsapmachine-jdkも確認．
$ brew info sapmachine-jdk🆑
Error: No available formula with the name "sapmachine-jdk"
Found a cask named "sapmachine-jdk" instead.
sapmachine-jdk: 12.0.1
https://sapmachine.io/
Not installed
From: https://github.com/Homebrew/homebrew-cask/blob/master/Casks/sapmachine-jdk.rb
==> Name
SapMachine OpenJDK Development Kit
==> Artifacts
sapmachine-jdk-12.0.1.jdk -> /Library/Java/JavaVirtualMachines/sapmachine-jdk-12.0.1.jdk (Generic Artifact)
$
AdoptOpenJDK
- IBM，Microsoft,Github，Slackが支援するJava開発コミュニティによるJDK．Oracleの反対勢力かな．
$ brew cask install caskroom/versions/adoptopenjdk8🆑
Updating Homebrew...
==> Auto-updated Homebrew!
Updated 1 tap (homebrew/core).
==> Updated Formulae
angular-cli exploitdb flow lazygit teleport
autorest faas-cli helmfile sonobuoy webtorrent-cli
==> Tapping caskroom/versions
Cloning into '/usr/local/Homebrew/Library/Taps/caskroom/homebrew-versions'...
remote: Enumerating objects: 204, done.
remote: Counting objects: 100% (204/204), done.
remote: Compressing objects: 100% (200/200), done.
remote: Total 204 (delta 9), reused 33 (delta 1), pack-reused 0
Receiving objects: 100% (204/204), 86.78 KiB | 356.00 KiB/s, done.
Resolving deltas: 100% (9/9), done.
Tapped 175 casks (222 files, 331.5KB).
==> Satisfying dependencies
==> Downloading https://github.com/AdoptOpenJDK/openjdk8-binaries/releases/download/jdk8u212-b03/OpenJD
==> Downloading from https://github-production-release-asset-2e65be.s3.amazonaws.com/140418865/07e4b900
######################################################################## 100.0%
==> Verifying SHA-256 checksum for Cask 'adoptopenjdk8'.
==> Installing Cask adoptopenjdk8
==> Running installer for adoptopenjdk8; your password may be necessary.
==> Package installers may write to any location; options such as --appdir are ignored.
Password:🆑
installer: Package name is AdoptOpenJDK
installer: Installing at base path /
installer: The install was successful.
🍺 adoptopenjdk8 was successfully installed!
$
$ java -version🆑
openjdk version "1.8.0_212"🈁
OpenJDK Runtime Environment (AdoptOpenJDK)(build 1.8.0_212-b03)
OpenJDK 64-Bit Server VM (AdoptOpenJDK)(build 25.212-b03, mixed mode)
$ which java🆑
/usr/bin/java🈁
$ ls -la /usr/bin/java🆑
lrwxr-xr-x 1 root wheel 74 5 7 00:33 /usr/bin/java -> /System/Library/Frameworks
/JavaVM.framework/Versions/Current/Commands/java
$
