标签：
Redhat Linux 6.5 安装JDK时，可能系统中已安装了老版本的JDK，这时要先卸载老版的，之后再安装新版本。
一．卸载openJDK
[root@master ~]# java -version
java version "1.7.0_45"
OpenJDK Runtime Environment (rhel-2.4.3.3.el6-x86_64 u45-b15)
OpenJDK 64-Bit Server VM (build 24.45-b08, mixed mode)
[root@master ~]# rpm -qa | grep jdk
java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64
java-1.6.0-openjdk-1.6.0.0-1.66.1.13.0.el6.x86_64
[root@master ~]# rpm -qa | grep gcj
[root@master ~]# java -version
java version "1.7.0_45"
OpenJDK Runtime Environment (rhel-2.4.3.3.el6-x86_64 u45-b15)
OpenJDK 64-Bit Server VM (build 24.45-b08, mixed mode)
[root@master ~]# yum -y remove java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64 Loaded plugins: product-id, refresh-packagekit, security, subscription-manager
This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
Setting up Remove Process
Resolving Dependencies
--> Running transaction check
---> Package java-1.7.0-openjdk.x86_64 1:1.7.0.45-2.4.3.3.el6 will be erased
--> Finished Dependency Resolution
Dependencies Resolved
====================================================================================================================
Package Arch Version Repository Size
====================================================================================================================
Removing:
java-1.7.0-openjdk x86_64 1:1.7.0.45-2.4.3.3.el6 @anaconda-RedHatEnterpriseLinux-201311111358.x86_64/6.5 90 M
Transaction Summary
====================================================================================================================
Remove 1 Package(s)
Installed size: 90 M
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Erasing : 1:java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64 1/1
Verifying : 1:java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64 1/1
Removed:
java-1.7.0-openjdk.x86_64 1:1.7.0.45-2.4.3.3.el6
Complete!
二．安装oracle JDK
创建安装目录，在/usr/java下建立安装路径，并将文件考到该路径下：
mkdir /usr/java
[root@master usr]# cd
[root@master ~]# ls
anaconda-ks.cfg Downloads jdk-7u79-linux-x64.rpm Pictures Templates
Desktop install.log jdk-7u79-linux-x64.tar.gz Public Videos
Documents install.log.syslog Music rabbitmq-server-3.6.0-1.noarch.rpm
[root@master ~]# cp -r jdk-7u79-linux-x64.rpm /usr/java
[root@master ~]# ls
anaconda-ks.cfg Downloads jdk-7u79-linux-x64.rpm Pictures Templates
Desktop install.log jdk-7u79-linux-x64.tar.gz Public Videos
Documents install.log.syslog Music rabbitmq-server-3.6.0-1.noarch.rpm
[root@master ~]# cd /usr/java
[root@master java]# ls
jdk-7u79-linux-x64.rpm jdk-8u20-linux-x64.rpm
[root@master java]#
将jdk-7u79-linux-x64.rpm上传到/usr/java下。然后，要给jdk-7u79-linux-x64.rpm
分配权限，具体的这里要给它可执行的权限，输入：chmod +x jdk-7u79-linux-x64.rpm
开始执行安装命令： rpm -ivh jdk-7u79-linux-x64.rpm
Preparing... ########################################### [100%]
1:jdk ########################################### [100%]
Unpacking JAR files...
rt.jar...
jsse.jar...
charsets.jar...
tools.jar...
localedata.jar...
jfxrt.jar...
[root@master java]#
2.设置环境变量。
#vi /etc/profile
在最后面加入 输入 i
JAVA_HOME=/usr/java/jdk1.7.0_79
PATH=$JAVA_HOME/bin:$PATH
CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export JAVA_HOME
export PATH
export CLASSPATH
保存退出：
按Esc ：wq回车即可，重启登录生效
四.验证环境变量配置成功
输入：which java 得到JAVA的执行路径，说明配置成功
/usr/java/jdk1.7.0_79/bin/java
输入：echo $JAVA_HOME
/usr/java/jdk1.7.0_79
[root@master ~]# echo $PATH
/usr/java/jdk1.7.0_79/bin:/usr/lib64/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin
标签：
原文地址：http://www.cnblogs.com/qinersky902/p/5247729.html
