Codec is a component that provides implementations for many common encoders and decoders such as Base64, Hex... Discovery component finds implementations for interfaces. Have a look at the component sites for more info.
In fact, there are more and more open source projects nowadays. Do you think some of them maybe *imported* into the upcoming J2SE? For example, in JDK 1.3, there is no logging in JDK, and log4j is an open project for this purpose, but then, in JDK 1.4, J2SE provides its own logging mechanism. Thus, what potential projects may SUN consider to import into J2SE 1.5 or 1.6? Nick