public List<SubjectDTO> getAllProfessorSubjects(int id) {
		List<SubjectDTO> professorSubjectsDTO = new ArrayList<>();
		List<Subject> subjects = subjectRepository.findAll();
		User u = userRepository.getOne(id);
		for (Subject s : subjects) {
			for (Professor professor : s.getProfessors()) {
				if (professor.getId() == u.getProfessor().getId()) {
					SubjectDTO subjectDTO = new SubjectDTO(s);
					List<ExamDTO> exams = new ArrayList<ExamDTO>();
					exams = getStudentsNextExams(professor.getId(), s.getId());
					subjectDTO.setExams(exams);
					professorSubjectsDTO.add(subjectDTO);

				}
			}
		}
		return professorSubjectsDTO;
	}