Blackberry Java Development Environment
The BlackBerry Java Development Environment (BlackBerry JDE) is a fully integrated development environment and simulation tool for building Java Platform, Micro Edition (Java® ME) applications for Java® based BlackBerry smartphones.
It’s a Mobile Information Device Profile (MIDP) compliant Java ME environment for developers who wish to maintain seamless portability in their wireless applications. In addition, the BlackBerry JDE provides a full suite of interfaces and utilities to take advantage of some of the unique features of the BlackBerry smartphone.
More information here.