c3p0 is a JDBC Connection pooling library I first published in 2002. It is very old-school, but i like to think it is still cool.
c3p0 v0.10.0 is the first major release — well, the first release at all — in a very long time. It now includes pluggable threading with loom support, much simplified connection testing by default, a more modern, more automated build, and many many fixes, improvements and enhancements.
https://github.com/swaldman/c3p0