JavaTM Application Isolation API
JSR-121 Public Review Draft
December 16, 2002
Pete Soper (Sun Microsystems, JSR sponsor)
Peter Donald Richard Houldsworth (Philips)
Doug Lea Norbert Kuck (SAP)
Michey Mehta (HP) Miles Sabin
Pat Tullmann (University of Utah) David Unitis (Oracle)
Matthew Webster (IBM) Kumanan Yogaratnam (Espial)

This is the Public Review Draft of the specification for JSR-121: JavaTM Application Isolation API.

Technical discussion is welcome by use of the open isolate-interest email list dedicated to this JSR.

Comments may also be sent via e-mail, in plain ASCII, to


The JSR-121 Specification covers API elements in the new package java.lang.isolate as well as elements added to package java.util.prefs. Example code is embedded in the specification to demonstrate usage. The best starting point for reading this specification is the java.lang.isolate package documentation. A list of frequently asked questions provides design rationale and clarification for particular points.

Embedded in the specification docs are two proposals for other JSRs:

A java.nio.channels.LinkChannel class proposed for a future NIO version defines a selectable channel for inter-isolate communication and a few other proposed API elements are present that support LinkChannel. Brown text highlights the NIO proposal.

Also included is a proposed set of J2ME subsets of the JSR-121 APIs, anticipating a fast track J2ME JSR effort aimed at enabling implementation and use of the APIs that can be supported with CDC/FPv1.0. A signature list and special tags are embedded within the specification to document the proposed subsets. The proposed CDC/FPv1.0 subset javadoc is also provided for convenience.

Changes since Community Draft

The change log documents changes made since the Community Review draft specification in detail (summarized version forthcoming).

Special thanks to Grzegorz Czajkowski of Sun Microsystems and Beth Hutchison of IBM for providing many hours of expert consultation.