Programname: Stringboolean isValid()void addActivity()«abstract»Activityects: ECTSname: Stringvoid toString()BasicCourseCourseSubjectModuleCourseElectiveCourseBasicProjectProjectvoid toString()SubjectModuleProjectBachelorProject{ ECTS = 15}{ ECTS ∈ {5, 10} }1..*0..*0..*614..8120..*30..*10..*8..