Ого, вау, переделал всю структуру, мне это очень понравилось

frontend/vue-project/src/models/Group.js

@@ -2,5 +2,6 @@ export default class Group{
     constructor(data) {
         this.id = data?.id;
         this.name = data?.name;
+        this.subjectIds = data?.subjectIds;
     }
 }

frontend/vue-project/src/pages/groups.vue

@@ -6,30 +6,102 @@
             <thead>
             <tr>
                 <th>Имя</th>
-                <th></th>
+                <th>Действия</th>
+                <th>Работа с группой</th>
+                <th>Работа с предметами</th>
             </tr>
             </thead>
             <tbody>
             <tr v-for="grp in groups" :key="grp.id">
                 <td>{{ grp.name }}</td>
                 <td>
-                    <td>
+                    <div class="d-flex flex-column">
-                        <button class="btn btn-primary mr-2" @click="openModal('edit', grp)">Изменить</button>
+                        <button class="btn btn-primary mb-2" @click="openModal('edit', grp)">Изменить</button>
-                    </td>
+                        <button class="btn btn-danger mb-2" @click="deleteGroup(grp.id)">Удалить</button>
-                    <td>
+                    </div>
-                        <button class="btn btn-danger" @click="deleteGroup(grp.id)">Удалить</button>
+                </td>
-                    </td>
+                <td>
-                    <td>
+                    <div class="d-flex flex-column">
-                        <button class="btn btn-primary mr-2" @click="OpenModelForStudents();getStudentsFromGroup(grp.id)">Просмотр студентов</button>
+                        <button class="btn btn-primary mb-2" @click="OpenModelForStudents(); getStudentsFromGroup(grp.id)">Просмотр студентов</button>
-                    </td>
+                        <button class="btn btn-primary mb-2" @click="OpenModelForAddStudents(grp); getStudentsFromUndefinedGroup()">Добавление студентов в группу</button>
-                    <td>
+                    </div>
-                        <button class="btn btn-primary mr-2" @click="OpenModelForSubjects();getSubjects(grp.id)">Просмотр предметов</button>
+                </td>
-                    </td>
+                <td>
+                    <div class="d-flex flex-column">
+                        <button class="btn btn-primary mb-2" @click="OpenModelForSubjects(); getSubjectsInGroup(grp.id)">Просмотр предметов</button>
+                        <button class="btn btn-primary mb-2" @click="OpenModelForAddSubjects('edit', grp);">Добавление предметов в группу</button>
+                    </div>
                 </td>
             </tr>
             </tbody>
         </table>
     </div>
+    <!--Форма для привязки предмета и групп    -->
+    <div class="modal" tabindex="-1" id="openModalForAddSubjects">
+        <div class="modal-dialog">
+            <div class="modal-content">
+                <div class="modal-header">
+                    <h5 class="modal-title">Добавление предметов</h5>
+                </div>
+                <div class="modal-body">
+                    <form>
+                        <div class="form-group">
+                            <label for="name">Имя:</label>
+                            <input readonly type="text" class="form-control" id="name" name="name" v-model="group.name">
+                        </div>
+                        <div class="form-group">
+                            <label for="name">Выберите предметы для добавления:</label>
+                            <ul class="list-group">
+                                <li class="list-group-item" v-for="subject in subjects" :key="subject.id">
+                                    <div class="form-check">
+                                        <input class="form-check-input" type="checkbox" v-model="selectedSubjects" :value="subject.id" v-bind:checked="open.includes(subject.id)" id="groupCheck{{ subject.id }}">
+                                        <label class="form-check-label" for="groupCheck{{ subject.id }}">{{ subject.name }}</label>
+                                    </div>
+                                </li>
+                            </ul>
+                        </div>
+                    </form>
+                </div>
+                <div class="modal-footer">
+                    <button type="button" class="btn btn-secondary" data-bs-dismiss="editModal" @click="closeModalForAddSubjects()">Закрыть</button>
+                    <button type="button" class="btn btn-primary" @click="addSubjectToGroup(group.id, selectedSubjects)">Добавить</button>
+                </div>
+            </div>
+        </div>
+    </div>
+    <!--    Модальное окно для добавления студентов в группу-->
+    <div class="modal" tabindex="-1" id="ModalForAddStudents">
+        <div class="modal-dialog">
+            <div class="modal-content">
+                <div class="modal-header">
+                    <h5 class="modal-title">Добавление студентов в группу</h5>
+                </div>
+                <div class="modal-body">
+                    <form>
+                        <div class="form-group">
+                            <label for="name">Имя:</label>
+                            <input type="text" class="form-control" id="name" name="name" v-model="group.name">
+                        </div>
+                        <div class="form-group">
+                            <label for="name">Выберите студентов для добавления:</label>
+                            <ul class="list-group">
+                                <li class="list-group-item" v-for="student in students" :key="student.id">
+                                    <div class="form-check">
+                                        <input class="form-check-input" type="checkbox" :id="'studentCheck' + student.id" :value="student.id" v-model="selectedStudents">
+                                        <label class="form-check-label" :for="'studentCheck' + student.id">{{ student.name }}</label>
+                                    </div>
+                                </li>
+                            </ul>
+                        </div>
+                    </form>
+                </div>
+                <div class="modal-footer">
+                    <button type="button" class="btn btn-secondary" data-bs-dismiss="editModal" @click="CloseModalForAddStudents()">Закрыть</button>
+                    <button type="button" class="btn btn-primary" @click="saveStudents(group.id)">Сохранить</button>
+                </div>
+            </div>
+        </div>
+    </div>
 <!--    Модальное окно для добавления и изменения-->
     <div class="modal" tabindex="-1" id="editModal">
         <div class="modal-dialog">
@@ -68,12 +140,18 @@
                                 <tr>
                                     <th>Имя</th>
                                     <th>Дата рождения</th>
+                                    <th></th>
                                 </tr>
                                 </thead>
                                 <tbody>
                                 <tr v-for="stud in students" :key="stud.id">
                                     <td>{{ stud.name }}</td>
                                     <td>{{ stud.birthDate }}</td>
+                                    <td>
+                                        <td>
+                                            <button class="btn btn-danger mr-2" @click="deleteStudentFromGroup(stud.id)">Удалить</button>
+                                        </td>
+                                    </td>
                                 </tr>
                                 </tbody>
                             </table>
@@ -103,7 +181,7 @@
                                 </tr>
                                 </thead>
                                 <tbody>
-                                <tr v-for="sbjct in subjects" :key="sbjct.id">
+                                <tr v-for="sbjct in subjectsInGroup" :key="sbjct.id">
                                     <td>{{ sbjct.name }}</td>
                                 </tr>
                                 </tbody>
@@ -123,9 +201,11 @@ import 'axios';
 import axios from "axios";
 import Group from "@/models/Group";
 import Student from "@/models/Student";
+import Subject from "@/models/Subject";
 export default {
     created() {
         this.getGroups();
+        this.getSubjects();
     },
     data() {
         return{
@@ -134,13 +214,18 @@ export default {
             group: new Group(),
             students: [],
             subjects: [],
+            selectedStudents: [],
+            open: [],
+            groupId: undefined,
+            selectedSubjects: [],
+            subjectsInGroup: [],
         }
     },
     methods: {
-        getSubjects(id){
+        getSubjectsInGroup(id){
             axios.get(this.URL + `group/${id}/getAllSubjects`)
                 .then(response => {
-                    this.subjects = response.data;
+                    this.subjectsInGroup = response.data;
                     console.log(response.data);
                 })
                 .catch(error => {
@@ -200,6 +285,7 @@ export default {
             document.getElementById("editModal").style.display = "none";
         },
         getStudentsFromGroup(groupId){
+            this.selectedStudents = [];
             axios.get(this.URL + `group/${groupId}/students`)
                 .then(response => {
                     this.students = response.data;
@@ -221,6 +307,87 @@ export default {
         closeModelForSubjects() {
             document.getElementById("ModelForSubjects").style.display = "none";
         },
+        OpenModelForAddStudents(group) {
+            this.group = { ...group };
+            document.getElementById("ModalForAddStudents").style.display = "block";
+        },
+        CloseModalForAddStudents() {
+            document.getElementById("ModalForAddStudents").style.display = "none";
+        },
+        saveStudents(id) {
+            axios.post(this.URL + `group/${id}/addStudents`,   this.selectedStudents)
+                .then(() => {
+                    this.getStudentsFromGroup(id);
+                    this.CloseModalForAddStudents();
+                    console.log(this.students);
+                })
+                .catch(error => {
+                    console.log(error);
+                });
+        },
+        getStudentsFromUndefinedGroup(){
+            axios.get(this.URL + `group/getStudentsUndefined`)
+                .then(response => {
+                    this.students = response.data;
+                    console.log(response.data);
+                })
+                .catch(error => {
+                    console.log(error);
+                });
+        },
+        deleteStudentFromGroup(id){
+            axios.delete(this.URL + `group/deleteStudentFromGroup/${id}`)
+                .then(() =>{
+                    this.getStudentsFromGroup();
+                })
+                .catch(error => {
+                console.log(error);
+            });
+        },
+        OpenModelForAddSubjects(status, group = null) {
+            if (status === "create") {
+                this.group = new Group();
+                this.group.status = "create";
+            } else if (status === "edit" && group) {
+                this.group = { ...group };
+                this.group.status = "edit";
+            }
+            this.open = this.group.subjectIds ? [...this.group.subjectIds] : []; // Создаём новый массив, чтобы избежать проблем с ссылками
+            this.loadSelectedSubjects(); // Загрузка выбранных групп при открытии модального окна
+            document.getElementById("openModalForAddSubjects").style.display = "block";
+        },
+        closeModalForAddSubjects() {
+            document.getElementById("openModalForAddSubjects").style.display = "none";
+            this.open = [...this.selectedSubjects]; // Обновление массива open значениями из selectedGroups
+            this.selectedSubjects = []; // Сброс выбранных групп
+            this.group = new Group(); // Сброс текущего предмета при закрытии модального окна
+        },
+        loadSelectedSubjects() {
+            // Загрузка выбранных групп из массива open
+            this.selectedSubjects = [...this.open];
+        },
+        addSubjectToGroup(id, list) {
+            axios
+                .post(this.URL + `group/${id}/addSubjectToGroup`, list)
+                .then(() => {
+                    this.closeModalForAddSubjects();
+                    this.getGroups(); // Обновляем список предметов после успешного добавления
+                    this.open = [...this.selectedSubjects]; // Обновляем массив выбранных групп
+                })
+                .catch((error) => {
+                    console.log(error);
+                });
+        },
+        getSubjects(){
+            axios.get(this.URL + "subject")
+                .then(response => {
+                    this.subjects = response.data;
+                    console.log(response.data);
+                })
+                .catch(error => {
+                    console.log(error);
+                });
+        },
     }
 }
 </script>

frontend/vue-project/src/pages/students.vue

@@ -15,7 +15,7 @@
             <tr v-for="stud in students" :key="stud.id">
                 <td>{{ stud.name }}</td>
                 <td>{{ stud.birthDate }}</td>
-                <td>{{ stud.groupName }}</td>
+                <td>{{stud.groupName || 'No Group'}}</td>
                 <td>
                     <td>
                         <button class="btn btn-primary mr-2" @click="openModal('edit', stud)">Изменить</button>
@@ -44,14 +44,6 @@
                             <label for="birthdate">Дата рождения:</label>
                             <input type="date" class="form-control" id="birthdate" name="birthdate" v-model="editedStudent.birthDate">
                         </div>
-                        <div class="form-group">
-                            <label for="group">Группа:</label>
-                            <select v-model="editedStudent.groupId" class="form-control">
-                                <option v-for="(group, index) in groups" :key="index" :value="group.id">
-                                    {{ group.name }}
-                                </option>
-                            </select>
-                        </div>
                     </form>
                 </div>
                 <div class="modal-footer">
@@ -98,8 +90,8 @@ export default {
                     console.log(error);
                 });
         },
-        getGroups(){
+        getGroups() {
-            axios.get(this.URL + "group")
+            axios.get(this.URL + "student/groups")
                 .then(response => {
                     this.groups = response.data;
                     console.log(response.data);
@@ -109,6 +101,8 @@ export default {
                 });
         },
         addStudent(student) {
+            console.log(student);
+            student.group = null;
             console.log(student);
             axios
                 .post(this.URL + "student", student)

frontend/vue-project/src/pages/subjects.vue

@@ -19,9 +19,6 @@
                     <td>
                         <button class="btn btn-danger" @click="deleteSubject(sbjct.id)">Удалить</button>
                     </td>
-                    <td>
-                        <button class="btn btn-primary mr-2" @click="openModalForAdd('edit', sbjct);">Добавить предметы в группы</button>
-                    </td>
                 </td>
             </tr>
             </tbody>
@@ -50,39 +47,6 @@
             </div>
         </div>
     </div>
-<!--Форма для привязки предмета и групп    -->
-    <div class="modal" tabindex="-1" id="openModalForAdd">
-        <div class="modal-dialog">
-            <div class="modal-content">
-                <div class="modal-header">
-                    <h5 class="modal-title">Добавление групп</h5>
-                </div>
-                <div class="modal-body">
-                    <form>
-                        <div class="form-group">
-                            <label for="name">Имя:</label>
-                            <input readonly type="text" class="form-control" id="name" name="name" v-model="subject.name">
-                        </div>
-                        <div class="form-group">
-                            <label for="name">Выберите группы для добавления:</label>
-                            <ul class="list-group">
-                                <li class="list-group-item" v-for="group in groups" :key="group.id">
-                                    <div class="form-check">
-                                        <input class="form-check-input" type="checkbox" v-model="selectedGroups" :value="group.id" v-bind:checked="open.includes(group.id)" id="groupCheck{{ group.id }}">
-                                        <label class="form-check-label" for="groupCheck{{ group.id }}">{{ group.name }}</label>
-                                    </div>
-                                </li>
-                            </ul>
-                        </div>
-                    </form>
-                </div>
-                <div class="modal-footer">
-                    <button type="button" class="btn btn-secondary" data-bs-dismiss="editModal" @click="closeModalForAdd()">Закрыть</button>
-                    <button type="button" class="btn btn-primary" @click="addSubjectToGroup(subject.id, selectedGroups)">Добавить</button>
-                </div>
-            </div>
-        </div>
-    </div>
 </template>
 <script>
 import 'axios';
@@ -92,40 +56,15 @@ import Group from "@/models/Group";
 export default {
     created() {
         this.getSubjects();
-        this.getGroups();
-        this.getAllSubjectGroup();
     },
-    mounted() {
-        const addModal = document.getElementById('editModal');
-        addModal.addEventListener('shown.bs.modal', function () {
-        })
-        const openModalForAdd = document.getElementById('openModalForAdd');
-        openModalForAdd.addEventListener('shown.bs.modal', function () {
-        })
-    },
-
     data() {
         return{
             subjects: [],
             URL: "http://localhost:8080/",
             subject: new Subject(),
-            groups: [],
-            selectedGroups: [],
-            AllSubjectGroup: [],
-            open: [],
         }
     },
     methods: {
-        getAllSubjectGroup(){
-            axios.get(this.URL + "subject/getAllSubjectGroup")
-                .then(response => {
-                    this.AllSubjectGroup = response.data;
-                    console.log(response.data);
-                })
-                .catch(error => {
-                    console.log(error);
-                });
-        },
         getSubjects(){
             axios.get(this.URL + "subject")
                 .then(response => {
@@ -164,27 +103,6 @@ export default {
                 })
             this.closeModal();
         },
-        openModalForAdd(status, subject = null) {
-            if (status === "create") {
-                this.subject = new Subject();
-                this.subject.status = "create";
-            } else if (status === "edit" && subject) {
-                this.subject = { ...subject };
-                this.subject.status = "edit";
-            }
-            this.open = this.subject.groupIds ? [...this.subject.groupIds] : []; // Создаём новый массив, чтобы избежать проблем с ссылками
-            this.loadSelectedGroups(); // Загрузка выбранных групп при открытии модального окна
-            document.getElementById("openModalForAdd").style.display = "block";
-        },
-
-        closeModalForAdd() {
-            document.getElementById("openModalForAdd").style.display = "none";
-            this.open = [...this.selectedGroups]; // Обновление массива open значениями из selectedGroups
-            this.selectedGroups = []; // Сброс выбранных групп
-            this.subject = new Subject(); // Сброс текущего предмета при закрытии модального окна
-        },
-
-
         openModal(status, subject = null) {
             if (status === "create") {
                 this.subject = new Subject();
@@ -198,38 +116,6 @@ export default {
         closeModal() {
             document.getElementById("editModal").style.display = "none";
         },
-        getGroups(){
-            axios.get(this.URL + "group")
-                .then(response => {
-                    this.groups = response.data;
-                    console.log(response.data);
-                })
-                .catch(error => {
-                    console.log(error);
-                });
-        },
-        saveSelectedGroups() {
-            // Сохранение выбранных групп в массив open
-            this.open = [...this.selectedGroups];
-        },
-
-        loadSelectedGroups() {
-            // Загрузка выбранных групп из массива open
-            this.selectedGroups = [...this.open];
-        },
-
-        addSubjectToGroup(id, list) {
-            axios
-                .post(this.URL + `subject/${id}/addSubjectToGroup`, list)
-                .then(() => {
-                    this.closeModalForAdd();
-                    this.getSubjects(); // Обновляем список предметов после успешного добавления
-                    this.open = [...this.selectedGroups]; // Обновляем массив выбранных групп
-                })
-                .catch((error) => {
-                    console.log(error);
-                });
-        },
     }
 }
 </script>

src/main/java/ru/IP_LabWorks/IP/University/Contoller/DTO/GroupDTO.java

@@ -2,16 +2,21 @@ package ru.IP_LabWorks.IP.University.Contoller.DTO;
 
 import ru.IP_LabWorks.IP.University.Model.Group;
 
+import java.util.List;
+
 public class GroupDTO {
     private long id;
     private String name;
 
+    private List<Long> subjectIds;
+
     public GroupDTO(){
 
     }
     public GroupDTO(Group group){
         this.id = group.getId();
         this.name = group.getName();
+        this.subjectIds = group.getSubjectIds();
     }
 
     public Long getId(){
@@ -29,4 +34,8 @@ public class GroupDTO {
     public void setName(String name){
         this.name = name;
     }
+
+    public List<Long> getSubjectIds(){
+        return subjectIds;
+    }
 }

src/main/java/ru/IP_LabWorks/IP/University/Contoller/DTO/StudentDTO.java

@@ -20,8 +20,9 @@ public class StudentDTO {
         this.id = student.getId();
         this.name = student.getName();
         this.birthDate = student.getBirthDate();
-        this.groupName = student.getGroup().getName();
+        if(student.getGroup() != null){
-        this.groupId = student.getGroup().getId();
+            this.groupName = student.getGroup().getName();
+        }
     }
 
     public String getGroupName() {

src/main/java/ru/IP_LabWorks/IP/University/Contoller/REST/GroupController.java

@@ -59,6 +59,28 @@ public class GroupController {
         return ResponseEntity.ok(subjects);
     }
 
+    @GetMapping("/getStudentsUndefined")
+    public ResponseEntity<List<Student>> getStudentsFromUndefinedGroup(){
+        List<Student> students = groupService.getStudentsUndefined();
+        return ResponseEntity.ok(students);
+    }
+
+    @PostMapping("/{id}/addStudents")
+    public void addStudentToGroup(@PathVariable Long id, @RequestBody @Valid List<Long> studentsIds){
+        groupService.addStudentToGroup(id, studentsIds);
+    }
+
+    @DeleteMapping("deleteStudentFromGroup/{id}")
+    public void deleteStudentFromGroup(@PathVariable Long id){
+        groupService.deleteStudentFromGroup(id);
+    }
+
+    @PostMapping("/{id}/addSubjectToGroup")
+    public void addSubjectToGroup(@PathVariable Long id, @RequestBody @Valid List<Long> subjectIds){
+        groupService.addSubjectToGroup(id, subjectIds);
+    }
+
+
 //    @PostMapping("/{id}/student")
 //    public StudentDTO setStudentToGroup(@PathVariable Long id,
 //                                        @RequestParam("studentId") Long studentId) {

src/main/java/ru/IP_LabWorks/IP/University/Contoller/REST/StudentController.java

@@ -1,20 +1,24 @@
 package ru.IP_LabWorks.IP.University.Contoller.REST;
 
 import org.springframework.web.bind.annotation.*;
+import ru.IP_LabWorks.IP.University.Contoller.DTO.GroupDTO;
 import ru.IP_LabWorks.IP.University.Contoller.DTO.StudentDTO;
+import ru.IP_LabWorks.IP.University.Service.GroupService;
 import ru.IP_LabWorks.IP.University.Service.StudentService;
 
 import jakarta.validation.Valid;
-import java.time.LocalDate;
+
 import java.util.List;
 
 @RestController
 @RequestMapping("/student")
 public class StudentController {
     private final StudentService studentService;
+    private final GroupService groupService;
 
-    public StudentController(StudentService studentService) {
+    public StudentController(StudentService studentService, GroupService groupService) {
         this.studentService = studentService;
+        this.groupService = groupService;
     }
 
     @GetMapping("/{id}")
@@ -31,12 +35,12 @@ public class StudentController {
 
     @PostMapping
     public StudentDTO createStudent(@RequestBody @Valid StudentDTO studentDTO){
-        return new StudentDTO(studentService.addStudent(studentDTO.getName(), studentDTO.getBirthDate(), studentDTO.getGroupId()));
+        return new StudentDTO(studentService.addStudent(studentDTO.getName(), studentDTO.getBirthDate()));
     }
 
     @PutMapping("/{id}")
     public StudentDTO updateStudent(@PathVariable Long id, @RequestBody @Valid StudentDTO studentDTO) {
-        return new StudentDTO(studentService.updateStudent(id, studentDTO.getName(), studentDTO.getBirthDate(), studentDTO.getGroupId()));
+        return new StudentDTO(studentService.updateStudent(id, studentDTO.getName(), studentDTO.getBirthDate()));
     }
 
     @DeleteMapping("/{id}")
@@ -44,4 +48,11 @@ public class StudentController {
         return new StudentDTO(studentService.deleteStudent(id));
     }
 
+    @GetMapping("/groups")
+    public List<GroupDTO> getGroups() {
+        return groupService.findAllGroups().stream()
+                .map(GroupDTO::new)
+                .toList();
+    }
+
 }

src/main/java/ru/IP_LabWorks/IP/University/Model/Group.java

@@ -8,6 +8,7 @@ import org.hibernate.annotations.OnDeleteAction;
 
 import javax.swing.*;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
 
@@ -89,4 +90,18 @@ public class Group {
         subjects.add(subject);
         subject.getGroups().add(this);
     }
+
+    public List<Long> getSubjectIds() {
+        if (subjects.isEmpty()) {
+            return Collections.emptyList();
+        } else {
+            List<Long> subjectIds = new ArrayList<>();
+            for (Subject subject : subjects) {
+                if (!subjectIds.contains(subject.getId())) {
+                    subjectIds.add(subject.getId());
+                }
+            }
+            return subjectIds;
+        }
+    }
 }

src/main/java/ru/IP_LabWorks/IP/University/Model/Student.java

@@ -25,10 +25,9 @@ public class Student {
     public Student() {
     }
 
-    public Student(String name, LocalDate birthDate, Group group) {
+    public Student(String name, LocalDate birthDate) {
         this.name = name;
         this.birthDate = birthDate;
-        this.group = group;
     }
 
     public Long getId() { return id; }
@@ -59,11 +58,13 @@ public class Student {
 
     @Override
     public String toString() {
+        String groupStr = (group != null) ? group.getName() : "No Group";
         return "Student{" +
                 "id=" + id +
                 ", name='" + name + '\'' +
                 ", birthDate='" + birthDate + '\'' +
                 ", age='" + getAge() + '\'' +
+                ", group='" + groupStr + '\'' +
                 '}';
     }
 

src/main/java/ru/IP_LabWorks/IP/University/Service/GroupService.java

@@ -1,6 +1,6 @@
 package ru.IP_LabWorks.IP.University.Service;
 
-import jakarta.persistence.EntityNotFoundException;
+import org.springframework.context.annotation.Lazy;
 import org.springframework.transaction.annotation.Transactional;
 import org.springframework.stereotype.Service;
 import org.springframework.util.StringUtils;
@@ -8,10 +8,9 @@ import ru.IP_LabWorks.IP.University.Model.Group;
 import ru.IP_LabWorks.IP.University.Model.Student;
 import ru.IP_LabWorks.IP.University.Model.Subject;
 import ru.IP_LabWorks.IP.University.Repository.GroupRepository;
-import ru.IP_LabWorks.IP.University.Repository.StudentRepository;
 import ru.IP_LabWorks.IP.University.Service.NotFoundException.GroupNotFoundException;
 
-import java.awt.desktop.OpenFilesEvent;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 
@@ -19,8 +18,13 @@ import java.util.Optional;
 public class GroupService {
     private final GroupRepository groupRepository;
 
-    public GroupService(GroupRepository groupRepository) {
+    private final StudentService studentService;
+    private final SubjectService subjectService;
+
+    public GroupService(GroupRepository groupRepository, StudentService studentService, @Lazy SubjectService subjectService) {
         this.groupRepository = groupRepository;
+        this.studentService = studentService;
+        this.subjectService = subjectService;
     }
 
     @Transactional
@@ -87,6 +91,41 @@ public class GroupService {
         }
     }
 
+    @Transactional
+    public List<Student> getStudentsUndefined(){
+        List<Student> students = new ArrayList<>();
+        for(Student student : studentService.findAllStudents()){
+            if(student.getGroup() == null){
+                students.add(student);
+            }
+        }
+        return students;
+    }
+
+    @Transactional
+    public void addStudentToGroup(Long groupId, List<Long> studentIds){
+        final Group currentGroup = findGroup(groupId);
+        for(Long studentId : studentIds) {
+            studentService.findStudent(studentId).setGroup(currentGroup);
+        }
+        groupRepository.save(currentGroup);
+    }
+
+    @Transactional
+    public void deleteStudentFromGroup(Long id){
+        studentService.findStudent(id).setGroup(null);
+    }
+
+    @Transactional
+    public void addSubjectToGroup(Long groupId, List<Long> subjectIds){
+        final Group currentGroup = findGroup(groupId);
+        currentGroup.setSubjects(new ArrayList<>());
+        for(Long subjectId : subjectIds) {
+            currentGroup.getSubjects().add(subjectService.findSubject(subjectId));
+        }
+        groupRepository.save(currentGroup);
+    }
+
 /*    @Transactional
     public Group addStudentToGroup(Long groupId, Long studentId) {
         Group group = findGroup(groupId);

src/main/java/ru/IP_LabWorks/IP/University/Service/StudentService.java

@@ -1,5 +1,7 @@
 package ru.IP_LabWorks.IP.University.Service;
 
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Lazy;
 import org.springframework.transaction.annotation.Transactional;
 import org.springframework.stereotype.Service;
 import org.springframework.util.StringUtils;
@@ -17,23 +19,17 @@ public class StudentService {
     private final StudentRepository studentRepository;
     private final GroupService groupService;
 
-    public StudentService(StudentRepository studentRepository, GroupService groupService) {
+    public StudentService(StudentRepository studentRepository,@Lazy GroupService groupService) {
         this.studentRepository = studentRepository;
         this.groupService = groupService;
     }
 
     @Transactional
-    public Student addStudent(String name, LocalDate birthDate, Long groupId){
+    public Student addStudent(String name, LocalDate birthDate){
         if (!StringUtils.hasText(name) || !StringUtils.hasText(String.valueOf(birthDate))) {
             throw new IllegalArgumentException("Student name or date is null or empty");
         }
-        Group group = null;
+        final Student student = new Student(name, birthDate);
-        try{
-            group = groupService.findGroup(groupId);
-        }catch (Exception ex){
-            group = null;
-        }
-        final Student student = new Student(name, birthDate,group);
         return studentRepository.save(student);
     }
 
@@ -49,14 +45,13 @@ public class StudentService {
     }
 
     @Transactional
-    public Student updateStudent(Long id, String name, LocalDate date, Long groupId) {
+    public Student updateStudent(Long id, String name, LocalDate date) {
         if (!StringUtils.hasText(name) || !StringUtils.hasText(String.valueOf(date))) {
             throw new IllegalArgumentException("Student name or date is null or empty");
         }
         final Student currentStudent = findStudent(id);
         currentStudent.setName(name);
         currentStudent.setBirthDate(date);
-        currentStudent.setGroup(groupService.findGroup(groupId));
         return studentRepository.save(currentStudent);
     }