JDK 下载官网:https://www.oracle.com/technetwork/java/javase/downloads/index.html
1. cat ~/.profile
2. vi /home/panda/bin/enviroment
3. JAVAHOME=/home/zbin/bin/jdk1.6.0_45 (实际JDK路径)
4. PATH="$JAVAHOME/bin:$PATH"
5. CLASSPATH=.:$JAVAHOME/lib
查看版本: java -version