jsp通过连接池连接oracle时出现以下异常
org.apache.tomcat.dbcp.dbcp.SQLNestedException:   Cannot   create   PoolableConnectionFactory   (Io   异常:   Connection   refused(DESCRIPTION=(TMP=)(VSNNUM=153092352)(ERR=12505)(ERROR_STACK=(ERROR=(CODE=12505)(EMFI=4)))))
at   org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:855)
at   org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:540)
at   org.apache.jsp.ShowInfo_jsp._jspService(org.apache.jsp.ShowInfo_jsp:61)
at   org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
at   javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at   org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322)
at   org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
at   org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
at   javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at   org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at   org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at   org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at   org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at   org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at   org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at   org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at   org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at   org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:868)
at   org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:663)
at   org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
at   org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
at   org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at   java.lang.Thread.run(Unknown   Source)
Caused   by:   java.sql.SQLException:   Io   异常:   Connection   refused(DESCRIPTION=(TMP=)(VSNNUM=153092352)(ERR=12505)(ERROR_STACK=(ERROR=(CODE=12505)(EMFI=4))))
at   oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
at   oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:179)
at   oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:333)
at   oracle.jdbc.driver.OracleConnection. <init> (OracleConnection.java:404)
at   oracle.jdbc.driver.OracleDriver.getConnectionInstance(OracleDriver.java:468)
at   oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:314)
at   org.apache.tomcat.dbcp.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:37)
at   org.apache.tomcat.dbcp.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:290)
at   org.apache.tomcat.dbcp.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:877)
at   org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:851)
...   22   more


------解决方案--------------------
不太懂，不过提示一下