on El Capitan, after installing the brew...
$ brew update
$ brew tap caskroom/cask
$ brew install Caskroom/cask/java
And Java 8 will be installed at /Library/Java/JavaVirtualMachines/jdk1.8.xxx.jdk/
Check version:
$ java -version
java version "1.8.0_74"
Java(TM) SE Runtime Environment (build 1.8.0_74-b02)
Java HotSpot(TM) 64-Bit Server VM (build 25.74-b02, mixed mode)