Centos7 安装 OpenJDK1.8

1.搜索可用的 openjdk1.8 包

[root@eric01 ~]# yum search java-1.8.0|grep openjdk

Repository epel is listed more than once in the configuration
Repository epel-debuginfo is listed more than once in the configuration
Repository epel-source is listed more than once in the configuration
Repodata is over 2 weeks old. Install yum-cron? Or run: yum makecache fast
java-1.8.0-openjdk.i686 : OpenJDK Runtime Environment
java-1.8.0-openjdk.x86_64 : OpenJDK Runtime Environment
java-1.8.0-openjdk-accessibility.i686 : OpenJDK accessibility connector
java-1.8.0-openjdk-accessibility.x86_64 : OpenJDK accessibility connector
java-1.8.0-openjdk-accessibility-debug.i686 : OpenJDK accessibility connector
java-1.8.0-openjdk-accessibility-debug.x86_64 : OpenJDK accessibility connector
java-1.8.0-openjdk-debug.i686 : OpenJDK Runtime Environment with full debug on
java-1.8.0-openjdk-debug.x86_64 : OpenJDK Runtime Environment with full debug on
java-1.8.0-openjdk-demo.i686 : OpenJDK Demos
java-1.8.0-openjdk-demo.x86_64 : OpenJDK Demos
java-1.8.0-openjdk-demo-debug.i686 : OpenJDK Demos with full debug on
java-1.8.0-openjdk-demo-debug.x86_64 : OpenJDK Demos with full debug on
java-1.8.0-openjdk-devel.i686 : OpenJDK Development Environment
java-1.8.0-openjdk-devel.x86_64 : OpenJDK Development Environment
java-1.8.0-openjdk-devel-debug.i686 : OpenJDK Development Environment with full
java-1.8.0-openjdk-devel-debug.x86_64 : OpenJDK Development Environment with
java-1.8.0-openjdk-headless.i686 : OpenJDK Runtime Environment
java-1.8.0-openjdk-headless.x86_64 : OpenJDK Runtime Environment
java-1.8.0-openjdk-headless-debug.i686 : OpenJDK Runtime Environment with full
java-1.8.0-openjdk-headless-debug.x86_64 : OpenJDK Runtime Environment with full
java-1.8.0-openjdk-javadoc.noarch : OpenJDK API Documentation
java-1.8.0-openjdk-javadoc-debug.noarch : OpenJDK API Documentation for packages
java-1.8.0-openjdk-javadoc-zip.noarch : OpenJDK API Documentation compressed in
java-1.8.0-openjdk-javadoc-zip-debug.noarch : OpenJDK API Documentation
java-1.8.0-openjdk-src.i686 : OpenJDK Source Bundle
java-1.8.0-openjdk-src.x86_64 : OpenJDK Source Bundle
java-1.8.0-openjdk-src-debug.i686 : OpenJDK Source Bundle for packages with
java-1.8.0-openjdk-src-debug.x86_64 : OpenJDK Source Bundle for packages with
​

2.安裝 openjdk1.8

yum -y install java-1.8.0-openjdk.x86_64 java-1.8.0-openjdk-devel.x86_64

安裝完成后 openjdk 的文件存放在/usr/lib/jvm

[root@eric01 jvm]# pwd
/usr/lib/jvm
[root@eric01 jvm]# ll
总用量 0
lrwxrwxrwx 1 root root 26 11月 26 22:39 java -> /etc/alternatives/java_sdk
lrwxrwxrwx 1 root root 32 11月 26 22:39 java-1.8.0 -> /etc/alternatives/java_sdk_1.8.0
lrwxrwxrwx 1 root root 40 11月 26 22:39 java-1.8.0-openjdk -> /etc/alternatives/java_sdk_1.8.0_openjdk
drwxr-xr-x 7 root root 68 11月 26 22:39 java-1.8.0-openjdk-1.8.0.191.b12-0.el7_5.x86_64
lrwxrwxrwx 1 root root 34 11月 26 22:39 java-openjdk -> /etc/alternatives/java_sdk_openjdk
lrwxrwxrwx 1 root root 21 11月 26 22:39 jre -> /etc/alternatives/jre
lrwxrwxrwx 1 root root 27 11月 26 22:39 jre-1.8.0 -> /etc/alternatives/jre_1.8.0
lrwxrwxrwx 1 root root 35 11月 26 22:39 jre-1.8.0-openjdk -> /etc/alternatives/jre_1.8.0_openjdk
lrwxrwxrwx 1 root root 51 11月 26 22:39 jre-1.8.0-openjdk-1.8.0.191.b12-0.el7_5.x86_64 -> java-1.8.0-openjdk-1.8.0.191.b12-0.el7_5.x86_64/jre
lrwxrwxrwx 1 root root 29 11月 26 22:39 jre-openjdk -> /etc/alternatives/jre_openjdk
​

3.配置环境变量

#java environment
export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.191.b12-0.el7_5.x86_64
export JRE_HOME=$JAVA_HOME/jre
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/jre/lib/tools.jar:$JRE_HOME/lib:$CLASSPATH
export PATH=$JAVA_HOME/bin:$PATH
​

更新环境变量：source /etc/profile

查看 java 版本

[root@eric01 classes]# java -version
openjdk version "1.8.0_191"
OpenJDK Runtime Environment (build 1.8.0_191-b12)
OpenJDK 64-Bit Server VM (build 25.191-b12, mixed mode)
​

至此，openjdk1.8 安装配置完成。