centos jdk切换

#这里找下载路径

http://www.oracle.com/technetwork/java/javase/downloads/jdk7-downloads-1880260.html

# 下载

wget http://download.oracle.com/otn-pub/java/jdk/7u79-b15/jdk-7u79-linux-x64.rpm?AuthParam=1447342638_39661edb37512ff85df21147bb170b87

rpm -ivh --force jdk-6u37-linux-amd64.rpm

rpm -ivh --force jdk-7u79.rpm

alternatives --install /usr/bin/java java /usr/java/jdk1.7.0_79/bin/java 7

alternatives --config java

而是骗子

#这个不行啊

#update-alternatives --install /usr/java/latest java /usr/java/jdk1.6.0_37 6

#update-alternatives --install /usr/java/latest java  /usr/java/jdk1.7.0_79/bin/java 7

#update-alternatives --install /usr/java/latest java /usr/java/jdk1.8.0_51 8

#这个

#alternatives --install /usr/bin/java java /usr/java/jdk1.7.0_79 7

#alternatives --install /usr/bin/javac javac /usr/java/jdk1.7.0_79 7

#alternatives --install /usr/bin/jar jar /usr/java/jdk1.7.0_79 7

切换命令：

alternatives --config java

##remove

#alternatives --remove java /usr/java/jdk1.6.0_37

#alternatives --remove java /usr/java/jdk1.7.0_79

##如果切换后不行么

#vi /etc/profile   文件末尾添加下面内容：

＃set environment variable

export JAVA_HOME=/usr/java/jdk1.7.0

export JRE_HOME=$JAVA_HOME/jre

export PATH=$PATH:$JAVA_HOME/bin

export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar

保存退出后

source /etc/profie

#或者  ”.“后是空格

. /etc/profile