1. 下载tar包
http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html
2. 在usr目录下建立java安装目录
root登录
mkdir -p /usr/java
3.将jdk-????-linux-x64.tar.gz上传到
/usr/java/
4.解压jdk到当前目录
tar -zxvf jdk-8u60-linux-x64.tar.gz
得到文件夹 jdk1.8.0_60
5.
vi /etc/profile
export JAVA_HOME=/usr/java/jdk1.8.0_131
export PATH=$PATH:$JAVA_HOME/bin
用 yum 安装的办法
========================
先查找包名
oracle@VM_64_75_centos dbs]$ yum -y list java*1.8*x86*
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
Installed Packages
java-1.8.0-openjdk.x86_64
java-1.8.0-openjdk-headless.x86_64
Available Packages
java-1.8.0-openjdk-accessibility.x86_64
java-1.8.0-openjdk-accessibility-debug.x86_64
java-1.8.0-openjdk-debug.x86_64
java-1.8.0-openjdk-demo.x86_64
java-1.8.0-openjdk-demo-debug.x86_64
java-1.8.0-openjdk-devel.x86_64
java-1.8.0-openjdk-devel-debug.x86_64
java-1.8.0-openjdk-headless-debug.x86_64
java-1.8.0-openjdk-src.x86_64
java-1.8.0-openjdk-src-debug.x86_64
javacc-manual.i386 4.0-3jpp.3 base
2.安装
[Iss@localhost ~]$ yum -y install
java-1.8.0-openjdk.x86_64
[Iss@localhost ~]$ yum -y install java-1.8.0-openjdk*
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirror.bit.edu.cn
* extras: mirror.bit.edu.cn
* updates: centos.ustc.edu.cn
base | 1.1 kB 00:00
base/primary | 995 kB 00:07
base 2789/2789
extras | 2.1 kB 00:00
extras/primary_db | 164 kB 00:02
updates | 1.9 kB 00:00
(1/8): giflib-4.1.3-7.3.3.el5.i386.rpm | 39 kB 00:00
(2/8): jpackage-utils-1.7.3-1jpp.3.el5.noarch.rpm | 60 kB
00:00
(3/8): tzdata-java-2014b-1.el5.i386.rpm | 172 kB 00:04
(4/8):
java-1.8.0-openjdk-demo-1.8.0.0-5.1.13.3.el5_10.i386.rpm | 2.2 MB
00:47
(5/8):
java-1.8.0-openjdk-devel-1.8.0.0-5.1.13.3.el5_10.i386.rpm | 15 MB
04:25
(6/8):
19% [============ ] 81 kB/s | 3.8 MB 03:19 ETA
最后一行就是在下载jdk了，这里我们安装jdk相关得全部包。
3.确认是否安装成功
[Iss@localhost ~]$ java -version
java version "1.8.0_30"
OpenJDK Runtime Environment (IcedTea6 1.13.3)
(rhel-5.1.13.3.el5_10-i386)
OpenJDK Client VM (build 23.25-b01, mixed mode)
正确显示了jdk版本信息就说明安装成功了。
4.默认情况下jdk安装得路径
默认一般安装在 /usr/lib/jvm 目录下
如
/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.131-3.b12.el7_3.x86_64/
vi /etc/profile
export
JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.131-3.b12.el7_3.x86_64
export PATH=$PATH:$JAVA_HOME/bin
由于我们得机器可能同时安装好几个版本得jdk，所以在/etc/alternatives目录下会有一个java链接到具体的java命令。这个/etc/alternatives/java会被/usr/bin/java链接。从而java命令就被设置到了shell环境中。
