1.移除多余的jdk

rpm -qa | grep ‘java|gcj‘ | xargs -t -I {} rpm -e --nodeps {}

rpm -e --nodeps *

rpm-qa|grep jdk

rpm -e --nodeps *

rpm -qa |grep gcj

rpm -qa |grep *

2.从Oracle网站上下载JDK-*.tar.gz

3.解压tar.gz文件，之后拷贝到 /usr/lib/jvm/下

4.配置update-alternatives

update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk1.7.0_80/bin/java 300

update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk1.7.0_80/bin/javac 300

5.配置环境变量

vi ~/.bash_profile

export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_80 export JRE_HOME=/usr/lib/jvm/jdk1.7.0_80/jre export CLASSPATH=.:$JAVA_HOME/bin/dt.jar:$JAVA_HOME/lib/tools.jar:$CLASSPATH export PATH=$JAVA_HOME/bin/:$PATH:$HOME/bin