tomcat 连不上 oracle，报：
java.sql.SQLException: Listener refused the connection with the following error: ORA-12505, TNS:listener does not currently know of SID given in connect descriptor
解决：
jdbc:oracle:thin:@(DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 10.1.1.1)(PORT = 1521))(LOAD_BALANCE = yes)(CONNECT_DATA = (SERVER = DEDICATED)(SERVICE_NAME = orcl)(FAILOVER_MODE = (TYPE = SELECT)(METHOD = BASIC)(RETRIES = 180)(DELAY = 5))))