What is jre under centos?
In centos, jre is the abbreviation of "Java Runtime Environment". It is a collection of environments necessary to run java programs, including JVM standard implementation and Java core class library; "java -vesion" can be used in centos system command to view version information.
#The operating environment of this article: centos 5.5 system, Dell G3 computer.
What is jre under centos
JRE is the abbreviation of Java Runtime Environment, which refers to the Java running environment and is a product of Sun. A collection of environments necessary to run JAVA programs, including JVM standard implementation and Java core class libraries.
Mainly consists of Java virtual machine, Java platform core classes and several supporting files. JRE does not include development tools, compilers, debuggers, or other tools. J2RE is the abbreviation of Java2 Runtime Environment, sometimes referred to as JRE.
Install the jre environment under centos
1. Download the jre package, address.
My environment is CentOS 5.5 32-bit, download the jre-8u171-linux-i586.tar.gz package.
2. Unzip and install
Extract jre-8u171-linux-i586.tar.gz to the current directory
tar -zxvf jre-8u171-linux-i586.tar.gz
Copy to the installation directory and authorize
mkdir -p /usr/java cp -rfp jre1.8.0_171/ /usr/java/ chown root.root -R * /usr/java/jre1.8.0_171
3. Configure environment variables
Add the following code to the end of the /etc/profile file
export JAVA_HOME=/usr/java/jre1.8.0_171 export JRE_HOME=/usr/java/jre1.8.0_171 export CLASSPATH=$JRE_HOME/lib/rt.jar:$JRE_HOME/lib/ext export PATH=$PATH:$JAVA_HOME/bin
Run
source /etc/profile
Run env to check that there are JAVA_HOME, JRE_HOME, and CLASSPATH in the current environment variables
4. Verification
Run
java -vesion to view version information
Recommended tutorial: "centos tutorial"
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