The Joe-E Subset of Java

Joe-E is a a subset of Java designed to build secure systems. The goal of object capability languages is to support the Principle of Least Authority (POLA), so that each object naturally receives the least privilege (i.e., least authority) needed to do its job. Joe-E is defined as a subset of Java that places additional restrictions on programs in order to eliminate sources of ambient authority that make enforcement of POLA impossible. The semantics of Java are preserved; any Joe-E program is a valid Java program. Since this allows use of the existing Java tool chain and programmer experience, we hope that Joe-E will support secure programming while remaining familiar to Java programmers everywhere.

A current draft of the specification and implementation are available at http://www.joe-e.org