1、官网下载jdk-7u45-linux-x64.tar.gz

载地址：http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

2、tar解压：tar -xzvf jdk-7u45-linux-x64.tar.gz

一般安装在/usr/local/文件夹下

3、配置环境变量：

<span style="font-size:18px;">$ vi /etc/profile</span>

<span style="font-size:18px;">在尾行加入：</span>

<span style="font-size:18px;">#set java environment
	export JAVA_HOME=/usr/local/jdk1.7.0_45
	export CLASSPATH=.:$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib
	export PATH=$PATH:$JAVA_HOME/bin:$JAVA_HOME/jre/bin</span>

<span style="font-size:18px;">4、使配置生效：</span>

<span style="font-size:18px;">#source /etc/profile</span>

<span style="font-size:18px;">5、检验是否成功安装：</span>

<span style="font-size:18px;">#java -version</span>

<span style="font-size:18px;">出现版本号信息说明成功安装：</span>

<span style="font-size:18px;">#java version "1.7.0_45"
	Java(TM) SE Runtime Environment (build 1.7.0_45-b18)
	Java HotSpot(TM) 64-Bit Server VM (build 24.45-b08, mixed mode)</span></span>

<span style="font-size:18px;">结束。

</span>