Hi
I am integrating c3p0 with hibernate. Prior to integration was able to retrieve and save the data using hibernate but after adding c3p0 properties i am getting following errors.

java.sql.SQLException: Connections could not be acquired from the underlying database!
at com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:118)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:690)

Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.
at com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.java:1422)

.BasicResourcePool] com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@1e01d652 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:
java.lang.NullPointerException
at oracle.jdbc.driver.OracleDriver.acceptsURL(OracleDriver.java:931)
at java.sql.DriverManager.getDriver(DriverManager.java:268)
at com.mchange.v2.c3p0.DriverManagerDataSource.driver(DriverManagerDataSource.java:240)
at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:131)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:156)
at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:145)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:200)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1086)
at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1073)
at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:44)
at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1810)
at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:696)
2014-04-30 16:28:56,361 [C3P0PooledConnectionPoolManager[identityToken->1hgesw6911e17f2m1dl7vmr|264d40df]-HelperThread-#1] WARN [com.mchange.v2.resourcepool.BasicResourcePool] Having failed to acquire a resource, com.mchange.v2.resourcepool.BasicResourcePool@5631db04 is interrupting all Threads waiting on a resource to check out. Will try again in response to new client requests.

Existing configuration with JNDI (working)

<property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>
<property name="hibernate.connection.datasource">java:comp/env/jdbc/ArticleWorksDS</property>
<property name="current_session_context_class">thread</property>
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

<mapping class="com.abc.aw.persistence.po.User"/>
<mapping class="com.abc.aw.persistence.po.UserAccess"/>

New Configuration with JNDI (Not working):
<property name="hibernate.connection.datasource">java:comp/env/jdbc/ArticleWorksDS</property>
<property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>
<property name="current_session_context_class">thread</property>
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>


<!--JDBC c3p0 connection pool -->
<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.max_size">20</property>
<property name="hibernate.c3p0.acquire_increment">1</property>
<property name="hibernate.c3p0.timeout">3600</property>

<mapping class="com.abc.aw.persistence.po.User"/>
<mapping class="com.abc.aw.persistence.po.UserAccess"/>

If I add user name and password details without using JNDI in hibernate-cfg.xml its working fine.

New Configuration without JNDI (working):
<property name="hibernate.connection.url">jdbc:oracle:thin:@richtestdb02:1521:devrpmrt</property>
<property name="hibernate.connection.username">article_works</property>
<property name="hibernate.connection.password">article_worksdev</property>
<property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>
<property name="current_session_context_class">thread</property>
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>


<!--JDBC c3p0 connection pool -->
<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.max_size">20</property>
<property name="hibernate.c3p0.acquire_increment">1</property>
<property name="hibernate.c3p0.timeout">3600</property>

<mapping class="com.abc.aw.persistence.po.User"/>
<mapping class="com.abc.aw.persistence.po.UserAccess"/>


Context.xml:

<Context>
<Resource name="jdbc/ArticleWorksDS"
type="oracle.jdbc.pool.OracleDataSource"
factory="oracle.jdbc.pool.OracleDataSourceFactory"
driverClassName="oracle.jdbc.driver.OracleDriver"
url="jdbc:oracle:thin:@richtestdb02:1521:devrpmrt"
validationQuery="SELECT 1 FROM SHOPPER"
userName="article_works"
password="article_worksdev"
maxActive="20"
maxIdle="10"
maxWait="-1" />
</Context>

New Jars added to configure c3p0 :
c3p0-0.9.5-pre8.jar
mchange-commons-java-0.2.7.jar

Can any one provide solution to resolve above errors?? Any pointers would help,thank you