PooledConnection.connectUsingDriver不加载JDBC驱动程序，因为driverClassName属性为null

Question

My web project has developed using spring 4.2.5.RELEASE and Hibernate 4.3.5.Final . My Project POM also has below dependency

<dependency>
            <groupId>com.oracle</groupId>
            <artifactId>ojdbc6</artifactId>
            <version>11.2.0.3</version>
        </dependency>
        <dependency>
            <groupId>commons-dbcp</groupId>
            <artifactId>commons-dbcp</artifactId>
            <version>1.2.2</version>
        </dependency>

My database context XML's - 1

  <?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
  xmlns:tx="http://www.springframework.org/schema/tx"
  xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
  http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd
  http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd">


  <context:component-scan base-package="com.test" />
  <context:annotation-config />
  <tx:annotation-driven transaction-manager="aTransaction" />

  <bean id="aDataSource"
    class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="${jdbc.driverClassName}" />
    <property name="url" value="${jdbc.url}" />
    <property name="username" value="${username}" />
    <property name="password" value="${password}" />
  </bean>

  <bean id="aSessionFactory"
    class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">

    <property name="dataSource">
      <ref bean="aDataSource" />
    </property>

    <property name="hibernateProperties">
      <props>
        <prop key="hibernate.dialect">${hibernate.dialect}</prop>
        <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
      </props>
    </property>

    <property name="packagesToScan" value="com.test.entity" />
  </bean>

  <bean id="aTransaction"
    class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory">
      <ref bean="aSessionFactory" />
    </property>
  </bean>
</beans>

XML-2

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
  http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd
  http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.2.xsd">


    <context:component-scan base-package="com.test2" />
  <context:annotation-config />
  <tx:annotation-driven transaction-manager="bTransaction" />

    <bean id="bDataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="${jdbc.driverClassName}" />
        <property name="url" value="${jdbc.url}" />
        <property name="username" value="${jdbc.user}" />
        <property name="password" value="${jdbc.pass}" />
    </bean>

    <bean id="bSessionFactory"
        class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">

        <property name="dataSource">
            <ref bean="bDataSource" />
        </property>

        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">${hibernate.dialect}</prop>
                <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
            </props>
        </property>

        <property name="packagesToScan" value="com.test.entity2" />
    </bean>

    <bean id="bTransaction"
        class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory">
            <ref bean="bSessionFactory" />
        </property>
    </bean>
</beans>

property File

# 2
jdbc.driverClassName=oracle.jdbc.driver.OracleDriver
jdbc.url=jdbc:oracle:thin:\\url
jdbc.user=test
jdbc.pass=test


# 1
jdbc.1url=jdbc:oracle:thin:@\\url2
1.username=test
2.password=test


# hibernate.X
hibernate.dialect=org.hibernate.dialect.OracleDialect
hibernate.show_sql=false
hibernate.hbm2ddl.auto=create-drop
package.to.scan=com.test.entity

My application working fine and all the rest services are able to fetch the data from DB. But while deploying in a server ie TCserver its throwing below warning during server startup and written in log file.Its not throwing this error in local tomcat. Also application are working fine but need to fix this warning.

org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver Not loading a JDBC driver as driverClassName property is null
org.apache.tomcat.jdbc.pool.ConnectionPool.init Unable to create initial connections of pool.

28-Jun-2018 20:22:51.243 SEVERE [localhost-startStop-1] org.apache.tomcat.jdbc.pool.ConnectionPool.init Unable to create initial connections of pool.
 java.sql.SQLException: The url cannot be null
    at java.sql.DriverManager.getConnection(DriverManager.java:649)
    at java.sql.DriverManager.getConnection(DriverManager.java:208)
    at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:308)
    at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:203)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:735)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:667)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:482)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:154)
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118)
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107)
    at org.apache.tomcat.jdbc.pool.DataSourceFactory.createDataSource(DataSourceFactory.java:560)
    at org.apache.tomcat.jdbc.pool.DataSourceFactory.getObjectInstance(DataSourceFactory.java:244)
    at org.apache.naming.factory.FactoryBase.getObjectInstance(FactoryBase.java:94)
    at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:321)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:839)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:159)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:827)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:173)
    at org.apache.catalina.core.NamingContextListener.addResource(NamingContextListener.java:1091)
    at org.apache.catalina.core.NamingContextListener.createNamingContext(NamingContextListener.java:661)
    at org.apache.catalina.core.NamingContextListener.lifecycleEvent(NamingContextListener.java:249)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:94)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5105)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:752)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:728)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734)
    at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:952)
    at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1823)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)

28-Jun-2018 20:22:51.243 WARNING [localhost-startStop-1] org.apache.naming.NamingContext.lookup Unexpected exception resolving reference
 java.sql.SQLException: The url cannot be null
    at java.sql.DriverManager.getConnection(DriverManager.java:649)
    at java.sql.DriverManager.getConnection(DriverManager.java:208)
    at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:308)
    at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:203)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:735)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:667)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:482)
    at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:154)
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118)
    at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107)
    at org.apache.tomcat.jdbc.pool.DataSourceFactory.createDataSource(DataSourceFactory.java:560)
    at org.apache.tomcat.jdbc.pool.DataSourceFactory.getObjectInstance(DataSourceFactory.java:244)
    at org.apache.naming.factory.FactoryBase.getObjectInstance(FactoryBase.java:94)
    at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:321)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:839)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:159)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:827)
    at org.apache.naming.NamingContext.lookup(NamingContext.java:173)
    at org.apache.catalina.core.NamingContextListener.addResource(NamingContextListener.java:1091)
    at org.apache.catalina.core.NamingContextListener.createNamingContext(NamingContextListener.java:661)
    at org.apache.catalina.core.NamingContextListener.lifecycleEvent(NamingContextListener.java:249)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:94)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5105)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:752)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:728)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734)
    at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:952)
    at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1823)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)

Answer 1

At last I figured out the issue . The issue is with resource ref entry of JNDI resource in web.xml .This issue has been suppressed in local Tomcat and did not throw any warning in local but in server it throws connection null warning. I removed the below snippet which is not required and the error went away.

<resource-ref>
    <description>Oracle Spring JNDI Datasource</description>
    <res-ref-name>jdbc/test</res-ref-name>
    <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>