From Sun documentation at:
JDK 6 Java Print Service -related APIs & Developer Guides -- from Sun Microsystems
javax.print: Provides the principal classes and interfaces for the Java Print Service API.
javax.print.attribute: Provides classes and interfaces that describe the types of Java Print Service attributes and how they can be collected into attribute sets.
javax.print.attribute.standard: Contains classes defining specific printing attributes.
javax.print.event: Contains event classes and listener interfaces for monitoring print services and the progress of a specific print job.