JDK JRE JVM
JDK: Java Development Kit (Java Developer Tools)
JRE: Java Runtime Environment (Java Runtime Environment)
JVM: Java Virtual Machine (virtual machine)
Uninstall JDK
My computer, properties, advanced system settings, environment variables, JavaHome, delete the installation directory of Java in the path, delete JavaHome in the environment variable, delete JavaHome in the environment variable Path, enter: Java -version in dos
Download JAVA
Configure environment variables
My computer, properties, advanced system settings, environment variables, new system variables, variable name: JAVA_HOME, variable value: jdk installation path
Configure Path variable
New construction:% JAVA_HOME% \ bin
New construction:% JAVA_HOME% \ jre \ bin
Check whether the installation is successful:
Enter in dos: Java -version