错误信息：
org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Listener refused the connection with the following error:
ORA-12514, TNS:listener does not currently know of service requested in connect descriptor
The Connection descriptor used by the client was:
(DESCRIPTION =    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.101)(PORT = 1521))    (CONNECT_DATA =      (SERVER = DEDICATED)      (SERVICE_NAME = ORCL)    )  )
)

Caused by: java.sql.SQLException: Listener refused the connection with the following error:
ORA-12514, TNS:listener does not currently know of service requested in connect descriptor
The Connection descriptor used by the client was:
(DESCRIPTION =    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.101)(PORT = 1521))    (CONNECT_DATA =      (SERVER = DEDICATED)      (SERVICE_NAME = ORCL)    )  )


at oracle.jdbc.driver.SQLStateMapping.newSQLException(SQLStateMapping.java:70)
at oracle.jdbc.driver.DatabaseError.newSQLException(DatabaseError.java:110)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:171)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:496)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:411)
at oracle.jdbc.driver.PhysicalConnection.(PhysicalConnection.java:490)
at oracle.jdbc.driver.T4CConnection.(T4CConnection.java:202)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:33)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:474)
at net.sf.log4jdbc.DriverSpy.connect(DriverSpy.java:717)
at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38)
at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:582)
at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1556)
at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1545)
... 105 more



解决方法：修改listener.ora
原：
SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = CLRExtProc)
      (ORACLE_HOME = E:\app\Val\product\11.2.0\dbhome_1)
      (PROGRAM = extproc)
      (ENVS = "EXTPROC_DLLS=ONLY:E:\app\Val\product\11.2.0\dbhome_1\bin\oraclr11.dll")
    )
 )

修改后：
SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = CLRExtProc)
      (ORACLE_HOME = E:\app\Val\product\11.2.0\dbhome_1)
      (PROGRAM = extproc)
      (ENVS = "EXTPROC_DLLS=ONLY:E:\app\Val\product\11.2.0\dbhome_1\bin\oraclr11.dll")
    )
    (SID_DESC =
      (GLOBAL_DBNAME = ORCL)
      (ORACLE_HOME = E:\app\Val\product\11.2.0\dbhome_1)
      (SID_NAME = ORCL)
    ) 
 )

这样以后，关掉Service和LISTENER。再启动Service和LISTENER，这样应该就可以了，注意顺序。
加上了面一段东西，意思是把LISTENER服务主动注册到进程监视器(pmon)中去。所以，但你启动了Serivce后，启动LISTENER的时候，会主动去注册到进程监视器(pmon)中去。所以不会有什么问题。但是反过却不行。
如果说没有添加那一段，情况正好相反，是由实例的pmon进程在LISTENER中注册服务，LISTENER为被动注册。所以需要先起LISTENER才可以。
总结一下，如果说你不加那段东西，那么就应该先起LISTENER，如果说你加了那段东西，就应该先起Serivce。
我试了一下，的确是这样。(不过在windows上，有时候会报错，重启一下再试就可以了)

此文章为整理加转载，参考文档：http://blog.sina.com.cn/s/blog_7c0e26230100t0ci.html