Six packages:

org.jdom

the classes that represent an XML document and its parts

org.jdom.input

classes for reading a document into memory

org.jdom.output

classes for writing a document onto a stream or other target (e.g. SAX or DOM app)

org.jdom.adapters

classes for hooking up to DOM implementations

org.jdom.filter

classes to mask parts of tree while navigating

org.jdom.transform

XSLT support via TrAX

org.jdom.xpath

XPath courtesy of Jaxen