The first step: there on his computer under examination is not installed JDK (Java Development Kit) (the latest version of July 2019 was installed JDK 1.8.0_181 version), by typing "java -version" in the terminal, can be tested .
Step Two: If you do not install the JDK, download the Oracle center of the venue's official website to download (need to sign the consent agreement and Oracle account to download) [ https://www.oracle.com/technetwork/java/javase/downloads/jdk8 -downloads-2133151.html ] (official website download speed is really slow, I downloaded a later JDK, search for "JDK for Mac download" from other sites)
The third step: after the download and installation is complete, by the terminal input "java -version" can be tested.
Step four: Download and install the Android application development IDE, Android Studio, I installed the 3.4.0 version. Can google the official website to download, you can also download the Chinese community [ http://www.android-studio.org/ ].