Umbra is an Eclipse plugin to edit byte code programs in textual form combined with an editor for specifications in Bytecode Modeling Language (BML). The current version of the tool is 1.0 and it is still in alpha stage.
The whole package contains three elements:
A paper presenting the Umbra editor can be found here (PDF).
We have developed a small case study using the tools. The case study is reported here.
The Umbra editor together with all the necessary libraries can be found in its update site http://www.mimuw.edu.pl/~alx/umbra/update/.
The sources can be viewed and downloaded from the SVN repository: