莫名其妙，日志中老是有無法連接oracle的異常
java.sql.SQLException: Io 異常: The Network Adapter could not establish the connection
先用oracle用戶登錄到服務器上
sqlplus /nolog
conn / as sysdba
運行了一些sql，一切正常呀，奇怪！
仔細想想，可能是lsnrctl的問題，打開listener.ora在下面插入以下內容：
(SID_DESC=
(GLOBAL_DBNAME = ORCL)
(ORACLE_HOME = /oracle/10g)
(SID_NAME = ORCL)
)
完成后的listener.ora如下
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = /oracle/10g)
(PROGRAM = extproc)
)
(SID_DESC=
(GLOBAL_DBNAME = ORCL)
(ORACLE_HOME = /oracle/10g)
(SID_NAME = ORCL)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1))
(ADDRESS = (PROTOCOL = TCP)(HOST = localhost.localdomain)(PORT = 1521))
)
)
保存后，重啟lsnrctl服務后就可以正常聯接了。