class Mentor(): def __init__(self, aName): self._students = None self._name = None self._name = aName self._students = [] def setName(self, aName): wasSet = False self._name = aName wasSet = True return wasSet def getName(self): return self._name def getStudent(self, index): aStudent = self._students[index] return aStudent def getStudents(self): newStudents = tuple(self._students) return newStudents def numberOfStudents(self): number = len(self._students) return number def hasStudents(self): has = len(self._students) > 0 return has def indexOfStudent(self, aStudent): index = (-1 if not aStudent in self._students else self._students.index(aStudent)) return index def isNumberOfStudentsValid(self): isValid = self.numberOfStudents() >= Mentor.minimumNumberOfStudents() and self.numberOfStudents() <= Mentor.maximumNumberOfStudents() return isValid @staticmethod def requiredNumberOfStudents(): return 4 @staticmethod def minimumNumberOfStudents(): return 4 @staticmethod def maximumNumberOfStudents(): return 4 def addStudent1(self, aNumber): from Student import Student if self.numberOfStudents() >= Mentor.maximumNumberOfStudents() : return None else : return Student(aNumber, self) def addStudent2(self, aStudent): wasAdded = False if (aStudent) in self._students : return False if self.numberOfStudents() >= Mentor.maximumNumberOfStudents() : return wasAdded existingMentor = aStudent.getMentor() isNewMentor = not (existingMentor is None) and not self == existingMentor if isNewMentor and existingMentor.numberOfStudents() <= Mentor.minimumNumberOfStudents() : return wasAdded if isNewMentor : aStudent.setMentor(self) else : self._students.append(aStudent) wasAdded = True return wasAdded def removeStudent(self, aStudent): wasRemoved = False if self == aStudent.getMentor() : return wasRemoved if self.numberOfStudents() <= Mentor.minimumNumberOfStudents() : return wasRemoved self._students.remove(aStudent) wasRemoved = True return wasRemoved def delete(self): i = len(self._students) while i > 0 : aStudent = self._students[i - 1] aStudent.delete() i -= 1 def __str__(self): return str(super().__str__()) + "[" + "name" + ":" + str(self.getName()) + "]" def addStudent(self, *argv): from Student import Student if len(argv) == 1 and isinstance(argv[0], str) : return self.addStudent1(argv[0]) if len(argv) == 1 and isinstance(argv[0], Student) : return self.addStudent2(argv[0]) raise TypeError("No method matches provided parameters") import os class Student(): def __init__(self, aNumber, aMentor): self._mentor = None self._number = None self._number = aNumber didAddMentor = self.setMentor(aMentor) if not didAddMentor : raise RuntimeError ("Unable to create student due to mentor. See http://manual.umple.org?RE002ViolationofAssociationMultiplicity.html") def setNumber(self, aNumber): wasSet = False self._number = aNumber wasSet = True return wasSet def getNumber(self): return self._number def getMentor(self): return self._mentor def setMentor(self, aMentor): from Mentor import Mentor wasSet = False if aMentor is None : return wasSet if aMentor.numberOfStudents() >= Mentor.maximumNumberOfStudents() : return wasSet existingMentor = self._mentor self._mentor = aMentor if not (existingMentor is None) and not existingMentor == aMentor : didRemove = existingMentor.removeStudent(self) if not didRemove : self._mentor = existingMentor return wasSet self._mentor.addStudent(self) wasSet = True return wasSet def delete(self): placeholderMentor = self._mentor self._mentor = None if not (placeholderMentor is None) : placeholderMentor.removeStudent(self) def __str__(self): return str(super().__str__()) + "[" + "number" + ":" + str(self.getNumber()) + "]" + str(os.linesep) + " " + "mentor = " + ((format(id(self.getMentor()), "x")) if not (self.getMentor() is None) else "null")