Cannot create JDBC driver of class '' for connect URL 'null'

server.xml

<GlobalNamingResources></GlobalNamingResources>안에 아래내용 추가

<Resource name="ResourceDB" type="javax.sql.DataSource"/>
  <ResourceParams name="ResourceDB1">
   <parameter>
    <name>validationQuery</name>
    <value>select * from emp</value>
   </parameter>
   <parameter>
    <name>maxWait</name>
    <value>5000</value>
   </parameter>
   <parameter>
    <name>maxActive</name>
    <value>4</value>
   </parameter>
   <parameter>
    <name>password</name>
    <value>tiger</value>
   </parameter>
   <parameter>
    <name>url</name>
    <value>jdbc:oracle:thin:@10.132.3.90:1521:ORCL</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>scott</value>
   </parameter>
  </ResourceParams>

web.xml(톰켓의 web.xml)

 <resource-ref>
  <description>DB Connection</description>
  <res-ref-name>ResourceDB</res-ref-name>
  <res-type>javax.sql.DataSource</res-type>
  <res-auth>Container</res-auth>
 </resource-ref>

생성된 <context></context>안에 아래내용 추가
   <ResourceLink name="ResourceDB" global="ResourceDB1" type="javax.sql.DataSource"/>