（求救）tomcat里连接池使用时出现的错误~~~~~~~~~

Question

连接池配置 server.xml 如下<?xml version='1.0' encoding='utf-8'?>
<Server>
  <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener"/>
  <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener"/>
  <GlobalNamingResources>
    <Environment name="simpleValue" type="java.lang.Integer" value="30"/>
    <Resource auth="Container" description="User database that can be updated and saved" name="UserDatabase" type="org.apache.catalina.UserDatabase"/>
    <ResourceParams name="UserDatabase">
      <parameter>
        <name>factory</name>
        <value>org.apache.catalina.users.MemoryUserDatabaseFactory</value>
      </parameter>
      <parameter>
        <name>pathname</name>
        <value>conf/tomcat-users.xml</value>
      </parameter>
    </ResourceParams>
  </GlobalNamingResources>
  <Service name="Catalina">
    <Connector acceptCount="100" connectionTimeout="20000" disableUploadTimeout="true" port="80" redirectPort="8443">
    </Connector>
    <Connector port="8009" protocol="AJP/1.3" protocolHandlerClassName="org.apache.jk.server.JkCoyoteHandler" redirectPort="8443">
    </Connector>
    <Engine defaultHost="localhost" name="Catalina">
      <Host appBase="webapps" name="localhost">
  <Context path="/mytest" docBase="D:/Program Files/Apache Software Foundation/Tomcat 5.0/webapps/mytest" debug="1"    reloadable="true" crossContext="true">
        <Logger className="org.apache.catalina.logger.FileLogger" prefix="localhost_log." suffix=".txt" timestamp="true"/>
<Resource name="DBConnPool" type="javax.sql.DataSource"/>
    <ResourceParams name="DBConnPool">      <parameter>
        <name>maxWait</name>
        <value>5000</value>
      </parameter>
      <parameter>
        <name>maxActive</name>
        <value>4</value>
      </parameter>
      <parameter>
        <name>password</name>
        <value>123456</value>
      </parameter>
      <parameter>
        <name>url</name>
        <value>jdbc:oracle:thin:@localhost:1521:oracle</value>
      </parameter>
      <parameter>
        <name>driverClassName</name>
        <value>oracle.jdbc.driver.OracleDriver</value>
      </parameter>
      <parameter>
        <name>maxIdle</name>
        <value>2</value>
      </parameter>
      <parameter>
        <name>username</name>
        <value>system</value>
      </parameter>
  <parameter>
        <name>factory</name>
        <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
      </parameter>
    </ResourceParams>
</Context>
      </Host>
      <Logger className="org.apache.catalina.logger.FileLogger" prefix="catalina_log." suffix=".txt" timestamp="true"/>
      <Realm className="org.apache.catalina.realm.UserDatabaseRealm"/>
    </Engine>
  </Service>
</Server>