centos配置java环境变量

vi /etc/profile.d/java.bash

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

source /etc/profile