数据库连接串的问题。（如果是集群数据库的话）
连接字符串应该改成如下：
由

 jdbc:oracle:thin:@(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.0.12)(PORT = 1521))(ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.0.22)(PORT = 1521))(LOAD_BALANCE = yes)(FAILOVER = ON)(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = rac)(FAILOVER_MODE=(TYPE = SELECT)(METHOD = BASIC)(RETIRES = 20)(DELAY = 15))))