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Yum download install

Use yum -y List Java or yum Search JDK to find a list of java-related installation packages

Yum -y list Java search

# yum -y list search demo$ yum -y list java Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.aliyun.com * updates: Mirrors.aliyun.com Available Packages java-1.6.0-openjdk.x86_64 1.1.6.0.41-1.13.13.1.el7... mirrors.aliyun.com Available Packages Java-1.6.0-openjdk.x86_64 1.1.6.0.41-1.13.13.1.el7... Java - 1.8.0 comes with - its - headless. X86_64 l: 1.8.0.212. B04-0. El7_6 Java - 1.8.0 comes with - its. X86_64 1:1. 8.0.212. B04-0. El7_6# yum search JDK search demo$ yum search jdk ====================================== N/S matched: jdk ====================================== copy-jdk-configs.noarch : JDKs Configuration Files Copier Java-1.8.0-openjdk.i686: OpenJDK Runtime Environment 8... java-11-openjdk-debug.x86_64 : OpenJDK Runtime Environment 11 with full debug onCopy the code

Install the JDK

Select a JDK version from the above list and do the actual installation

$yum install java-1.8.0-openjdk.x86_64 Installed: Java - 1.8.0 comes with - its. X86_64 1:1. 8.0.292. B10-1. El7_9 Dependency Installed: Atk. X86_64 0:2.28.1-2.el7 copy-jdk-configs. Noarch 0:3.3-10.el7_5 giflib.x86_64 0:4.1.6-9.el7 GTK - update - icon - cache. X86_64 3-0. 22.30-6. El7... Chkconfig.x86_64 0:1.7.6-1.el7 Dependency Updated: chkconfig.x86_64 0:1.7.6-1.el7 Complete!Copy the code

If the preceding information is displayed, JDK is successfully installed

Configure environment variables such as JAVA_HOME

The default directory for installing JDK through yum is /usr/lib/jvm

$ls -l /usr/lib/jvm total 0 drwxr-xr-x 3 root root 16 Aug 3 22:53 java-1.8.0-openjdk-1.8.0.292.b10-1.el7_9.x86_64 LRWXRWXRWX 1 root root 21 Aug 3 22:53 JRE -> /etc/alternatives/jre LRWXRWXRWX 1 root root 27 Aug 3 22:53 JRE-1.8.0 -> /etc/alternatives/jre_1.8.0 LRWXRWX 1 root root 35 Aug 3 22:53 JRE-1.8.0-openjdk -> /etc/alternatives/jre_1.8.0_openjdk LRWXRWXRWX 1 root root 51 Aug 3 22:53 Jre-1.8.0-openjdk-1.8.0.292.b10-1.el7_9.x86_64 Java-1.8.0-openjdk-1.8.0.292.b10-1.el7_9.x86_64 / JRE LRWXRWXRWX 1 root root 29 Aug 3 22:53 JRE-openjdk -> /etc/alternatives/jre_openjdkCopy the code

You need to add the JDK installation path to JAVA_HOME to the environment variable

Edit the file vi /etc/profile

At the end of the file add:

#set java environmentJAVA_HOME = / usr/lib/JVM/jre - 1.6.0 - its. X86_64 PATH =$PATH:$JAVA_HOME/bin
CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export JAVA_HOME CLASSPATH PATH
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After modifying the file, run the./etc/profile or source /etc/profile command to make it take effect

Verification after installation is complete

After the configuration is complete, verify that the preceding configuration is successful. If the Java version information is displayed, the JDK is successfully installed

$ java -version
openjdk version "1.8.0 comes with _292"
OpenJDK Runtime Environment (build 1.8.0_292-b10)
OpenJDK 64-Bit Server VM (build 25.292-b10, mixed mode)
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Error: No matching Packages to list

The preceding problem is usually caused by the timeout of accessing the centos foreign source during the search. Change into domestic yum source

Backup the original yum source before replacement,

cd /etc/yum.repos.d/

mv CentOS-Base.repo CentOS-Base.repo_bak
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Replace domestic yum sources

# netease yum source:
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.163.com/.help/CentOS7-Base-163.repo
yum clean all
yum makecache

# Alibaba Cloud yum
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
yum clean all
yum makecache

# epel source
yum -y install epel-release
yum clean all
yum makecache
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The above three sources basically meet the needs of the development of YUM sources