centos配置jdk

########## config jdk ##########
export JAVA_HOME=/usr/local/java/jdk1.7.0_79
export CLASSPATH=.:${JAVA_HOME}/lib:${JAVA_HOME}/jre/lib
export PATH=${JAVA_HOME}/bin:$PATH

########## config hadoop ##########
export HADOOP_HOME=/usr/hadoop/hadoop-2.7.3
export PATH=$HADOOP_HOME/bin:$PATH

lxw@19:08:51:~$ which javac
/home/lxw/Downloads/jdk1.8.0/bin//javac
lxw@19:08:54:~$ which java
/usr/bin/java
lxw@19:12:11:~$ echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/home/lxw/Downloads/jdk1.8.0/bin/