Programming exercises are an important part of an introductory course in programming. To improve the focus on encapsulation, requirements-based testing and give better feedback given to the students during their work, we have created an Eclipse-based plugin called JExercise. Based on a model of an exercise, it presents the structure of requirements to the student and allows her to test the code by running accompanying JUnit tests. Categories and Subject Descriptors K.3.2 [Computers and Education]: Computer and Information