JDBC API -  .

DbConnectionBroker - - A pure Java package for handling multiple concurrent database connections. DbConnectionBroker creates a broker with a very simple interface for handing out and returning database connections from a configurable pool of connections. Also RandomGUID (utility class generates cryptographically strong random GUIDs in the standard format). [Open source.

DBPool - Java Database Connection Pooling - - A free JDBC connection pooling library featuring easy setup, connection validation, statement caching, time expiry. [Open source.

FireStorm/DAO Code Generator for JDBC - - FireStorm/DAO imports database schema definitions from SQL scripts or from live databases via JDBC and then generates a complete data-access tier based on JDBC.

Java Client Database (JCDatabase) - - A simplified version of JDBC that runs on both the server and as part of client applications. [Commercial.

Java Guru - JDBC FAQ - - A list of frequently asked questions about JDBC.

JDBC Drivers and Vendors - - A directory of JDBC-Driver-Vendors.

JDBCFacade - - A library for making JDBC easier to use and less error prone while encouraging a clean separation between persistence and domain logic. [Open source, MIT License.

Octopus Java/XML ETL Tool - - A simple Java-based Extraction, Transformation, and Loading (ETL) tool. It may connect to any JDBC data sources and perform transformations defined in an XML file. [Open source, LGPL.

PoolMan - - Offers configurable JDBC pools to multiple databases and SQL query/ResultSet cache. Generic Java object pooling is also available. [LGPL.

P6Spy - - Logs all queries between any JDBC application and any database with no code changes required. [Open source.

Webopedia.com - JDBC - - Describes the term JDBC and lists links with additional information.