mysql - org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null' -

i working on web based project using spring ,hybernate +jpa .i trying configure jta transactions atomkios backend mysql. not able setup application work mysql. web server tomcat 5.5.i trying cal jndi configured datasource .. here code

persistence.xml:

  <persistence-unit name="exhub" transaction-type="jta">     <provider>org.hibernate.ejb.hibernatepersistence</provider>       <jta-data-source>java:comp/env/jdbc/exampleweb</jta-data-source>         <mapping-file>meta-inf/orm.xml</mapping-file>    <class>com.evolvus.common.model.talogin</class>    <class>com.evolvus.common.model.tauser</class>               -----------------              -----------------              <properties>             <property name="hibernate.transaction.manager_lookup_class"              value="com.atomikos.icatch.jta.hibernate3.transactionmanagerlookup"/>             </ properties>       </persistence-unit> </persistence> 

orm.xml:

<description>evolvus solutions</description>  <package>com.evolvus.common.model</package>    <entity class="com.evolvus.common.model.tauser" name="tauser">   <table name="ta_user" />   <attributes>    <id name="userid">    <column name="user_id"/>     <generated-value strategy="table" />    </id>    <basic name="username">     <column name="user_name" length="50" />    </basic>    </attributes>  </entity>   ---------------   --------------   ---------------  </entity-mappings> 

config.xml:

 <beans: bean id="sessionfactory"    class="org.springframework.orm.hibernate3.localsessionfactorybean">   <beans: property name="usetransactionawaredatasource"    value="true" />    <beans: property name="hibernateproperties">    <beans: props>     <beans: prop key="hibernate.dialect">${database.target}</beans:prop>     <beans: prop key="hibernate.connection.isolation">3</beans:prop>     <beans: prop key="hibernate.current_session_context_class">jta</beans:prop>     <beans: prop key="hibernate.transaction.factory_class">com.atomikos.icatch.jta.hibernate3.atomikosjtatransactionfactory     </beans: prop>     <beans: prop key="hibernate.transaction.manager_lookup_class">com.atomikos.icatch.jta.hibernate3.transactionmanagerlookup     </beans: prop>     <beans: prop key="hibernate.connection.release_mode">on_close</beans: prop>     <beans: prop key="hibernate.show_sql">false</beans: prop>    </beans: props>   </beans: property>  </beans: bean>   <beans: bean id="jpatemplate" class="org.springframework.orm.jpa.jpatemplate">   <beans: property name="entitymanagerfactory">    <beans: ref bean="entitymanagerfactory" />   </beans: property>  </beans: bean>  <beans: bean id="entitymanagerfactory"   class="org.springframework.orm.jpa.localcontainerentitymanagerfactorybean">   <beans: property name="persistenceunitname" value="payhub" />   <beans: property name="jpavendoradapter">    <beans:bean     class="org.springframework.orm.jpa.vendor.hibernatejpavendoradapter">     <beans: property name="generateddl" value="false" />     <beans: property name="showsql" value="true" />     <beans: property name="databaseplatform" value="${database.target}" />    </beans: bean>   </beans: property>   <beans: property name="persistencexmllocation">    <beans: value>classpath:meta-inf/persistence.xml</beans:value>   </beans: property>  </beans: bean> </beans: beans> 

and configured jndi in tomcat 5.5

apache software foundation\tomcat 5.5\conf.xml:

 <resource       name="jdbc/exampleweb"       type="javax.sql.datasource"       maxactive="4"       maxidle="2"       username="root"       maxwait="5000"       validationquery="select=1"       driverclassname="com.mysql.jdbc.driver"       password="roopt"         url="jdbc\:mysql\://localhost\:3306/welcomehub"/>    , application\web.xml    <resource-ref>    <description>paymentsdatabase</description>    <res-ref-name>jdbc/exampleweb</res-ref-name>    <res-type>javax.sql.datasource</res-type>    <res-auth>container</res-auth>    <res-sharing-scope>shareable</res-sharing-scope> </resource-ref>  

my server staring fine when trying access db data getting following error in web browser

org.springframework.jdbc.cannotgetjdbcconnectionexception: not jdbc connection; nested exception org.apache.tomcat.dbcp.dbcp.sqlnestedexception: cannot create jdbc driver of class '' connect url 'null' org.springframework.jdbc.datasource.datasourceutils.getconnection(datasourceutils.java:82)

help me

i think application not finding mysql connector jar file or url misconfigured.

try following

1. put mysql connector jar file under tomcat/common/lib gets picked before webapp classes.

2. change context.xml have resource below.

     
   <resource  name="jdbc/exampleweb"     auth="container"     type="javax.sql.datasource"     maxactive="100"     maxidle="30"     username="root"     maxwait="10000"     driverclassname="com.mysql.jdbc.driver"     password="roopt"       url="jdbc:mysql://localhost:3306/welcomehub"/>