安装方式一 jdk环境
干净的环境 将tar包解压到 /usr/local下 版本为jdk-8u211-linux-x64.tar.gz 路径为/usr/local/jdk1.8.0_211
/usr/local 在当前用户下执行此环境变量(将本机配置好jdk环境)
#!/bin/bash
wget http://192.168.130.150/jdk/jdk-8u211-linux-x64.tar.gz
tar xf jdk-8u211-linux-x64.tar.gz -C /usr/local/
echo "export JAVA_HOME=/usr/local/jdk1.8.0_211" >> /etc/profile.d/jdk8.sh
echo "export CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/jar/tools.jar:$JAVA_HOME/jre/lib" >> /etc/profile.d/jdk8.sh
echo "export PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH" >> /etc/profile.d/jdk8.sh
echo "export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/apr/lib" >> /etc/profile.d/jdk8.sh
chmod +x /etc/profile.d/jdk8.sh
source /etc/profile.d/jdk8.sh
java -version
如果用脚本 需要在外面命令行执行 source /etc/profile.d/jdk8.sh 因为脚本里面加载了环境变量，外面还没有执行，重启亦可以
安装方式二 openjdk
查看CentOS自带JDK是否已安装
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[root@test ~]# yum list installed |grep java |
若有自带安装的JDK，应如下操作进行卸载CentOS系统自带Java环境
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[root@test ~]# java -versionjava version "1.7.0_181"OpenJDK Runtime Environment (rhel-2.6.14.8.el6_9-x86_64 u181-b00)OpenJDK 64-Bit Server VM (build 24.181-b00, mixed mode)[root@test ~]# yum -y remove java-1.7.0-openjdk*[root@test ~]# yum -y remove tzdata-java.noarch[root@test ~]# java --version-bash: /usr/bin/java: No such file or directory |
查看yum库中的Java安装包
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[root@test ~]# yum -y list java*Loaded plugins: fastestmirrorLoading mirror speeds from cached hostfile* base: centos.ustc.edu.cn* extras: centos.ustc.edu.cn* updates: centos.ustc.edu.cnbase | 3.7 kB 00:00 extras | 3.4 kB 00:00 updates | 3.4 kB 00:00 Available Packagesjava-1.5.0-gcj.x86_64 1.5.0.0-29.1.el6 base java-1.5.0-gcj-devel.x86_64 1.5.0.0-29.1.el6 base java-1.5.0-gcj-javadoc.x86_64 1.5.0.0-29.1.el6 base java-1.5.0-gcj-src.x86_64 1.5.0.0-29.1.el6 base java-1.6.0-openjdk.x86_64 1:1.6.0.40-1.13.12.6.el6_8 updatesjava-1.6.0-openjdk-demo.x86_64 1:1.6.0.40-1.13.12.6.el6_8 updatesjava-1.6.0-openjdk-devel.x86_64 1:1.6.0.40-1.13.12.6.el6_8 updatesjava-1.6.0-openjdk-javadoc.x86_64 1:1.6.0.40-1.13.12.6.el6_8 updatesjava-1.6.0-openjdk-src.x86_64 1:1.6.0.40-1.13.12.6.el6_8 updatesjava-1.7.0-openjdk.x86_64 1:1.7.0.111-2.6.7.2.el6_8 updatesjava-1.7.0-openjdk-demo.x86_64 1:1.7.0.111-2.6.7.2.el6_8 updatesjava-1.7.0-openjdk-devel.x86_64 1:1.7.0.111-2.6.7.2.el6_8 updatesjava-1.7.0-openjdk-javadoc.noarch 1:1.7.0.111-2.6.7.2.el6_8 updatesjava-1.7.0-openjdk-src.x86_64 1:1.7.0.111-2.6.7.2.el6_8 updatesjava-1.8.0-openjdk.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-debug.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-demo.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-demo-debug.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-devel.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-devel-debug.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-headless.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-headless-debug.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-javadoc.noarch 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-javadoc-debug.noarch 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-src.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava-1.8.0-openjdk-src-debug.x86_64 1:1.8.0.101-3.b13.el6_8 updatesjava_cup.x86_64 1:0.10k-5.el6 base java_cup-javadoc.x86_64 1:0.10k-5.el6 base java_cup-manual.x86_64 1:0.10k-5.el6 base javacc.x86_64 4.1-0.5.el6 base javacc-demo.x86_64 4.1-0.5.el6 base javacc-manual.x86_64 4.1-0.5.el6 base javassist.noarch 3.9.0-6.el6 base javassist-javadoc.noarch 3.9.0-6.el6 base |
以yum库中java-1.8.0为例, "*"表示将java-1.8.0的所有相关Java程序都安装上
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[root@test ~]# yum -y install java-1.8.0-openjdk* |
查看刚安装的Java版本信息。
输入："java -version" 可查看Java版本
输入："javac" 可查看Java的编译器命令用法
备注：一个环境，要用安装包就都用，要用yum也就都用yum，方便以后排错，openjdk有可能在有些环境下报错