download
Download URL:
http://www.oracle.com/technetwork/java/javase/downloads/jdk9-downloads-3848520.html
Take a screenshot
Install
After downloading, double-click to install
Modify the installation path
Wait for the installation to complete
Click to close
cmd command line window input java -version
The jdk version is 1.8. Go and modify the system variables
Reopen a cmd command line window after modification
Confirm whether it is the jdk9 we installed
OK, complete the installation, view the installation directory file
Compared with jdk8, it is found that the jre folder is missing
Compare jdk8
in jdk8
Install jdk comes with jre, even if jre is not selected, the jre file will be included after the installation is complete
custom install jre
If jdk9 installs jre, just customize the installation
