centos7.2 安装java8

 

 查看是否有内置的java环境：

 

[root@localhost ~]# 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)

 查看已安装的java：

[root@localhost ~]# rpm -qa | grep java
java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64
tzdata-java-2013g-1.el6.noarch
java-1.6.0-openjdk-1.6.0.0-1.66.1.13.0.el6.x86_64

分别执行命令yum删除以上3个： 

[root@localhost ~]# yum remove java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64
[root@localhost ~]# yum remove java-1.6.0-openjdk-1.6.0.0-1.66.1.13.0.el6.x86_64
[root@localhost ~]# yum remove tzdata-java-2013g-1.el6.noarch

 

或者通过rpm -e删除：

[root@localhost ~]# rpm -e --nodeps java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64
[root@localhost ~]# rpm -e --nodeps java-1.6.0-openjdk-1.6.0.0-1.66.1.13.0.el6.x86_64
[root@localhost ~]# rpm -e --nodeps tzdata-java-2013g-1.el6.noarch

 

例如，下面是删除java 1.7时的过程：

[root@localhost ~]# yum remove java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64
Loaded plugins: fastestmirror, refresh-packagekit, security
Setting up Remove Process
Resolving Dependencies
--> Running transaction check
-->xxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxx
xxxxxxxxxx
Installed size: 90 M

Is this ok [y/N]: y   (屏幕停在这里时输入y)

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!

可通过命令确认是否删除成功：

[root@localhost ~]# java
-bash: /usr/bin/java: 没有那个文件或目录
[root@localhost ~]# javac
-bash: javac: command not found
[root@localhost ~]# rpm -qa | grep java
不输出信息

 

 ==================================================================================

 安装java8

这里我下载的是压缩包，进行离线安装

官方下载地址：http://download.oracle.com/otn-pub/java/jdk/8u111-b14/jdk-8u111-linux-x64.tar.gz

将安装包放到/usr/local目录下后

命令进入到local目录：

[root@localhost local]# cd /usr/local/

 查看目录下的文件：

[root@localhost local]# ls
bin  games  jdk-8u111-linux-x64.tar.gz  lib    libexec  share
etc  include  lib64  sbin     src

解压jdk-8u111-linux-x64.tar.gz：

[root@localhost local]# tar –xzvf jdk-8u111-linux-x64.tar.gz

获取解压后java目录绝对路径：

[root@localhost local]# cd jdk1.8.0_111/
[root@localhost jdk1.8.0_111]# pwd
/usr/local/jdk1.8.0_111

 配置环境变量：

[root@localhost local]# vi /etc/profile

 在export PATH USER LOGNAME MAIL HOSTNAME HISTSIZE HISTCONTROL

下面添加：

export PATH USER LOGNAME MAIL HOSTNAME HISTSIZE HISTCONTROL
export JAVA_HOME=/usr/local/jdk1.8.0_111
export PATH=$JAVA_HOME/bin:$PATH

 保存并退出后执行命令source /etc/profile使修改的profile文件生效

[root@localhost jdk1.8.0_111]# source /etc/profile

 输入java，javac验证配置，到此处java环境配置完成。