Ubuntu下配置jdk

一、下载

• jdk:http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

二、安装JDk

2.1、解压jdk

1.创建一个目录

ln0491@ln0491-virtual-machine:/$ sudo mkdir /usr/local/develoment
[sudo] password for ln0491: 
ln0491@ln0491-virtual-machine:/$ ls /usr/local/
bin  develoment  etc  games  include  lib  man  sbin  share  src
ln0491@ln0491-virtual-machine:/$ 

2.将jdk文件cp到这个目录下

ln0491@ln0491-virtual-machine:/$ sudo cp /home/ln0491/Downloads/jdk-8u31-linux-x64.tar.gz /usr/local/develoment/
ln0491@ln0491-virtual-machine:/$ ls /usr/local/develoment/
jdk-8u31-linux-x64.tar.gz
ln0491@ln0491-virtual-machine:/$ 

3. 解压

sudo tar -zxvf jdk-8u31-linux-x64.tar.gz 

4.备份配置文件

cd /home/ln0491/
 cp .bashrc .bash_bak

5.编辑配置文件 vi .bashrc

在末尾添加

export JAVA_HOME=/usr/local/develoment/jdk1.8.0_31/

export JRE_HOME=${JAVA_HOME}/jre  
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib  
export PATH=${JAVA_HOME}/bin:$PATH

别一种写法:和Windows一样

export JAVA_HOME=/usr/local/develoment/jdk1.8.0_31/
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar  
export PATH=$PATH:$JAVA_HOME/bin:$JAVA_HOME/jre/bin

6.为了让更改立即生效，请在终端执行如下命令：

source .bashrc 

7.查看jdk版本

ln0491@ln0491-virtual-machine:~$ java -version
java version "1.8.0_31"
Java(TM) SE Runtime Environment (build 1.8.0_31-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.31-b07, mixed mode)
ln0491@ln0491-virtual-machine:~$ 

2.2、 配置环境变量

全局配置：/etc/profile文件中配置：

个人用户配置:/home/用户名/.bashrc ：只对这具用户有效 

这里用的是个人用户配置,也可以配置/etc/profile文件，使所有用户都有效