About gradle : Build system based on the Groovy language!
More Information: https://www.gradle.org/
Steps:

1. Open Terminal by pressing command+space, type terminal and hit Enter key.
2. Run

   ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" < /dev/null 2> /dev/null

3. Install

   brew install gradle

Done!