Common Errors and solutions for Tomcat connection pool Configuration

1. Cannot create JDBC driver of class ''for connect url''

Problem: The JDBC driver is not found, but the class value in the prompt is null. Therefore, we can conclude that Tomcat does not find the resource configuration information in server. xml. Possible causes include:

(1) No resource is configured;

(2) the location of resource configuration information is incorrect.

(3) The driverclassname and URL are incorrectly spelled.

Solution: Make sure that the resource is correctly configured and placed in the defaultcontext or context configuration section.

2. Cannot create JDBC driver of class 'xxx' for connect url''

Solution: the configuration of the database Driver Class Name XXX is incorrect. Check and modify it. If you confirm it is correct, the driver library cannot be found, copy a jar file to Tomcat/common/lib.

3. Cannot create JDBC driver of class ''for connect URL 'xxx'

Solution: the configured URL string syntax is incorrect. Check and modify the syntax.

4. Cannot create poolableconnectionfactory, cause: Io exception: Connection refused

Problem: the connection pool factory object cannot be created because the connection is denied.

Solution: Check the URL string. The server address, port, database name, database instance name, and other information may be incorrect. Modify.

5. No suitable driver has no matching driver.

Analysis: The driver configuration is incorrect. Check whether the common/lib sub-directory of Tomcat contains the database driver jar.

6. Cannot create resource instance cannot create a data source instance

Problem: commons-dbcp-1.1.jar not found (versions may be different)

Solution: copy the commons-dbcp-1.1.jar library file to the tomcat/common/lib subdirectory.

7. root cause:

Java. Lang. noclassdeffounderror: ORG/Apache/commons/collections/cursorablelinkedlist

Problem: The commons-collections.jar cannot be found.

Solution: copy the commons-collections.jar library file to the tomcat/common/lib subdirectory.

8. root cause:

Java. Lang. noclassdeffounderror: ORG/Apache/commons/pool/impl/genericobjectpool

Problem: commons-pool-1.1.jar not found (versions may be different ).

Solution: copy the commons-pool-1.1.jar library file to the tomcat/common/lib subdirectory.