Search Java version and install:
$ brew tap caskroom/versions
$ brew cask search java
==> Exact Match
java ✔
==> Partial Matches
charles-applejava eclipse-javascript java6 netbeans-java-ee yourkit-java-profiler
eclipse-java java-jdk-javadoc java8 netbeans-java-se
$ brew cask install java6
$ brew cask install java8
Check existing JDK:
$ /usr/libexec/java_home -V
Matching Java Virtual Machines (4):
10, x86_64: "Java SE 10" /Library/Java/JavaVirtualMachines/jdk-10.jdk/Contents/Home
1.8.0_172, x86_64: "Java SE 8" /Library/Java/JavaVirtualMachines/jdk1.8.0_172.jdk/Contents/Home
1.6.0_65-b14-468, x86_64: "Java SE 6" /Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home
1.6.0_65-b14-468, i386: "Java SE 6" /Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home
/Library/Java/JavaVirtualMachines/jdk-10.jdk/Contents/Home
Switch JDK version may be done through jenv. See this link for detail.
Right now, I have
/Library/Java $ ls -la
total 0
drwxr-xr-x 6 root wheel 192 Apr 20 09:47 .
drwxr-xr-x+ 66 root wheel 2112 Apr 6 11:57 ..
drwxr-xr-x 2 root wheel 64 Jul 15 2017 Extensions
lrwxr-xr-x 1 root wheel 64 Apr 20 09:47 Home -> /Library/Java/JavaVirtualMachines/jdk1.8.0_172.jdk/Contents/Home
drwxr-xr-x 5 root wheel 160 Apr 20 09:47 JavaVirtualMachines
lrwxr-xr-x 1 root wheel 59 Apr 4 16:26 MacOS -> /Library/Java/JavaVirtualMachines/jdk-10.jdk/Contents/MacOS
So, export JAVA_HOME=/Library/Java/Home will then send to Java 8, alghouth with a lack of definition it is Java 10 (which is at /Library/Java/JavaVirtualMachines/jdk-10.jdk/Contents/Home rather than /Library/Java/JavaVirtualMachines/jdk-10.jdk/Contents/MacOS).