Matlab is a programming environment that provides a large and accessibletoolbox for programming applications with high level of mathematical content.However it is a programming environment that targets a specic type of applicationand currently does not provide wide usability for implementing graphicswith emphasis on user interfaces and interactive design. In the other hand, Javais a well established development environment suitable for any type of graphicalprogramming. Together Matlab and Java make it possible to create applicationswith advanced mathematical computations as well as a well designed graphicaluser interface. This thesis discusses ways to integrate Java with Matlab and howto adapt an existing Matlab program with a Java-based graphical user interface.