Filters and Interceptors:
Filter is configured in web.xml but interceptor is configured in applicationContext.xml.Filters are more powerful, for example they allow for exchanging the request and response objects that are handed down the chain. Interceptor just allows custom pre-processing with the option of prohibiting the execution of the handler itself.

C3P0 is an open source JDBC connection pool distributed along with Hibernate in the lib directory. Hibernate will use its org.hibernate.connection.C3P0ConnectionProvider for connection pooling if you sethibernate.c3p0.* properties.