Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified
解决办法：
1. 退出oracle，用root登陆；
2. root命令行下输入：
[root@localhost ~]# xhost local:oracle non-network local connections being added to access control list
屏幕提示
xhost: bad hostname "non-network"
xhost: bad hostname "non-network"
xhost: bad hostname"local"
xhost: bad hostname "connetcions"
xhost: bad hostname "being"
xhost: bad hostname "added"
xhost: bad hostname "access"
xhost: bad hostname "control"
xhost: bad hostname "list"
3. 再试试su oracle
[root@localhost ~]# su - oracle