Connectivity to backend database not verified

Problem Scenario:

Application deployed on Weblogic connected to Oracle database. Calling save() action through struts, spring and hibernate tiers gives the following exception:

[@APPNAME@] WARN [ExecuteThread: '10' for queue: 'weblogic.kernel.Default'] SQLErrorCodesFactory.getErrorCodes(232) | Error while extracting database product name - falling back to empty error codes
org.springframework.jdbc.support.MetaDataAccessException: Error while extracting DatabaseMetaData; nested exception is java.sql.SQLException: Closed Connection
java.sql.SQLException: Closed Connection
 at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:125)
 at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:162)
 at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:227)

The following error is thrown when testing the connection pool in Weblogic:

Warning! Connectivity to backend database not verified. This is either because required connection pool attributes "TestConnectionsOnReserve" or "TestConnectionsOnRelease" have not been enabled, or an invalid value has been specified for attribute "TestTableName". Please check the server log for more details..

Solution:

In Weblogic console, click on the relevant connection pool, select tab configuration -> connection, show Advanced Options. Check the option as shown below:

Test Reserved Connections   Specifies whether WebLogic Server tests a connection before giving it to the client. (You must specify a Test Table Name below.)