Ubuntu设置环境变量并立即生效

转载于：http://www.cnblogs.com/zhangpengshou/p/3537619.html

# /etc/profile: system-wide .profile file for the Bourne shell (sh(1))
 # and Bourne compatible shells (bash(1), ksh(1), ash(1), ...).
     
 if [ -d /etc/profile.d ]; then
   for i in /etc/profile.d/*.sh; do
     if [ -r $i ]; then
       . $i
     fi
   done
     
 JAVA_HOME=/usr/hadoop/jdk1.6.0_25
 export JAVA_HOME
 PATH=$PATH:$JAVA_HOME/bin
 export PATH
 CLASSPATH=.:$JAVA_HOME/lib
 export CLASSPATH
     
   unset i
 fi
     
 if [ "$PS1" ]; then
   if [ "$BASH" ]; then
     # The file bash.bashrc already sets the default PS1.
     # PS1='\h:\w\$ '
     if [ -f /etc/bash.bashrc ]; then
       . /etc/bash.bashrc
     fi
   else
     if [ "`id -u`" -eq 0 ]; then
       PS1='# '
     else
       PS1='$ '
     fi
   fi
 fi