1> 安装Homebrew
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
2> 安装Jenkins
brew install jenkins
此时会提示：
Updating Homebrew...
jenkins: Java 1.8 is required to install this formula.
JavaRequirement unsatisfied!
You can install with Homebrew-Cask:
brew cask install homebrew/cask-versions/java8
You can download from:
https://www.oracle.com/technetwork/java/javase/downloads/index.html
Error: An unsatisfied requirement failed this build.
3> 安装上面的提示安装Java
brew cask install homebrew/cask-versions/java8
安装完成后再次执行步骤2的命令，安装成功后会提示：
Note: When using launchctl the port will be 8080.
To have launchd start jenkins now and restart at login:
brew services start jenkins
Or, if you don't want/need a background service you can just run:
jenkins
4> 启动Jenkins，然后在浏览器中输入http://localhost:8080
brew services start jenkins
5> 停止Jenkins
brew services stop jenkins
