- 先查一下java版本，
java -version
2.查出jdk旧版相关文件并删除它
rpm -qa|grep java
java-1.6.0-openjdk-1.6.0.0-1.66.1.13.0.el6.x86_64
tzdata-java-1513g-1.el6.noarch
java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64
rpm -e --nodeps java-1.6.0-openjdk-1.6.0.0-1.66.1.13.0.el6.x86_64
rpm -e --nodeps tzdata-java-1513g-1.el6.noarch
rpm -e --nodeps java-1.7.0-openjdk-1.7.0.45-2.4.3.3.el6.x86_64
- java -version 再次查找版本号
yum install lrzsz -y
rz upload jdk-8u151-linux-x64.tar.gz
JDK官网下载页面：
本次下载安装版本为：jdk1.8.0_151
wget https://download.oracle.com/otn-pub/java/jdk/8u151-b09/42970487e3af4f5aa5bca3f542482c60/jdk-8u151-linux-x64.tar.gz?AuthParam=1553435391_8796bf6e0ec2984c2635f13bda307604 --no-check-certificate
# 此地址仅供参考
注意：使用wget下载后的文件名可能异常，需要重命名（可同时移动到安装目录）
mv jdk-8u151-linux-x64.tar.gz\?AuthParam\=1512975825_b6f4d6db4f306de31c42215c4b2fec67
/opt/jdk-8u151-linux-x64.tar.gz
解压：
tar zxvf jdk-8u151-linux-x64.tar.gz
进入解压后的目录，并确保当前路径为:/opt/jdk1.8.xxxx
[root@localhost jdk1.8.0_151]# pwd
/usr/local/jdk1.8.0_151
添加环境变量
vim /etc/profile.d/java.sh
JAVA_HOME=/opt/jdk1.8.0_151/
JAVA_BIN=/opt/jdk1.8.0_151/bin
JRE_HOME=/opt/jdk1.8.0_151/jre
PATH=$PATH:/opt/jdk1.8.0_151/bin:/opt/jdk1.8.0_151/jre/bin
CLASSPATH=/opt/jdk1.8.0_151/jre/lib:/opt/jdk1.8.0_151/lib:/opt/jdk1.8.0_151/jre/lib/charsets.jar
export JAVA_HOME JAVA_BIN JRE_HOME PATH CLASSPATH
source环境变量文件
source /etc/profile.d/java.sh
查看java版本
[root@localhost jdk1.8.0_151] # java -version
java version "1.8.0_151"
Java(TM) SE Runtime Environment (build 1.8.0_151-b09)
Java HotSpot(TM) 64-Bit Server VM (build 25.151-b09, mixed mode)
也可以按如下格式写环境变量配置：
JAVA_HOME=/opt/jdk1.8.0_151/
CLASSPATH=$JAVA_HOME/lib/tools.jar:$JAVA_HOME/lib/dt.jar
PATH=$PATH:$JAVA_HOME/bin:$PATH
export JAVA_HOME PATH CLASSPATH
