JDK1.8 deployment under Windos:
installation
Go to Oracle's official website and download the JDK.
JDK is called JAVA Development Kit, SE EE ME and so on.
SE is used here.
Download and install path
The first installation path is JDK
The second installation path is JRE
Be sure to distinguish between these two . You can't choose the wrong one when using the environment variable configuration later! It is recommended to simplify the installation path for future learning. For example F: \ xx
Environment variable configuration
Right click this computer under Win10-Advanced System Settings-Advanced-Environment Variables
Create a new variable in the system variable, the variable name is JAVA_HOME. This is convenient for the system to find and reduce the repeated use of absolute paths
Mine is F: \ JAVA ( The JAVA path here is the path of the JDK and not the path of the JRE has been emphasized earlier)
Then find the path in the system variable, which is the environment variable.
Create two new ones (be careful not to delete others, which may affect the operation of the system)
%JAVA_HOME%\bin;
%JAVA_HOME%\jre\bin;
Remember to be sure
This configures the environment variables
Win + R enters the run interface, enter cmd run command dos window,
Check if the environment variable is set
Enter set path in the dos interface
See if there are environment variables just configured
If there is, it succeeds!
JDK environment deployment under Linux
First download the JDK Linux version on Oracle's official website
Here I use Centos 7 operating system with Gnome graphical interface
Download and unzip to a folder
Remember the version name, for example mine is jdk1.8.0_181
I named it java
Then start to configure environment variables
Install vim (my own Baidu)
Enter vim / etc / profile on the command line (modify environment variables)
Add at the end
JAVA_HOME= / java /jdk1.8.0_181
CLASSPATH=.:$JAVA_HOME/lib/tools.jar
PATH=$JAVA_HOME/bin:$PATH
export JAVA_HOME CLASSPATH PATH
Then save and exit: wq
At last
source / etc / profile makes environment variables take effect
Last test is successful
java -version
The version number is correct
Written a long time ago. . .
