This Pure-Java library reads & writes a variety of image formats, including fast parsing of image info (size, color space, icc profile, etc.) and metadata.
This library is pure Java. It's slow, consequently, but perfectly portable. It's easier to use than ImageIO/JAI/Toolkit (Sun/Java's image support), supports more formats (and supports them more correctly). It also provides easy access to metadata.
Although not yet version 1.0, sanselan is working and is used by a number of projects in production.