finishing many functions

Author: Hattinger04

src/main/java/io/github/Hattinger04/course/model/CourseService.java

@@ -64,37 +64,45 @@ public Teacher getCourseTeacher(Course course) {
 	}
 
 	public void setCourseTeacher(Course course, Teacher teacher) {
-		
+		teacherRepository.save(teacher);
+		courseRepository.addUserToCourse(teacher.getId(), course.getId());
 	}
 
 	// TODO: working with student / teacher table 
-	public void addStudentToCourse(Course course, User student) {
-		
+	public void addStudentToCourse(Course course, Student student) {
+		studentRepository.save(student); 
+		courseRepository.addUserToCourse(student.getId(), course.getId());
 	}
 
-	public void addStudentsToCourse(Course course, Set<User> student) {
-	
+	public void addStudentsToCourse(Course course, Set<Student> students) {
+		for(Student student : students) {
+			studentRepository.save(student); 
+			courseRepository.addUserToCourse(student.getId(), course.getId());
+		}
 	}
 
-	public void removeStudentFromCourse(Course course, User student) {
-
+	public void removeStudentFromCourse(Course course, Student student) {
+		studentRepository.delete(student);
+		courseRepository.removeUserFromCourse(student.getId(), student.getId());
 	}
 
-	public void removeStudentsFromCourse(Course course, Set<User> student) {
-
+	public void removeStudentsFromCourse(Course course, Set<Student> students) {
+		for(Student student : students) {
+			studentRepository.delete(student);
+			courseRepository.removeUserFromCourse(student.getId(), student.getId());
+		}
 	}
 
 	public boolean isUserTeacher(Course course, User user) {
-		if(isUserInCourse(course, user)) {
-			// TODO
-			return true; 
-		}
-		return false; 
+		return courseRepository.isUserTeacher(user.getId(), course.getId()) != 0; 
+	}
+	
+	public boolean isUserStudent(Course course, User user) {
+		return courseRepository.isUserStudent(user.getId(), course.getId()) != 0; 	
 	}
 
 	public boolean isUserInCourse(Course course, User user) {
-		// TODO
-		return false; 
+		return courseRepository.isUserStudent(user.getId(), course.getId()) != 0 || courseRepository.isUserTeacher(user.getId(), course.getId()) != 0; 	
 	}
 
 	public Exercise createExercise(Exercise exercise) {

src/main/java/io/github/Hattinger04/course/model/UserCourse.java

@@ -0,0 +1,11 @@
+package io.github.Hattinger04.course.model;
+
+import lombok.Getter;
+import lombok.Setter;
+
+public class UserCourse {
+	@Getter @Setter
+	private int user_id; 
+	@Getter @Setter
+	private int course_id; 
+}

src/main/java/io/github/Hattinger04/course/model/course/CourseRepository.java

@@ -2,8 +2,12 @@
 
 import java.util.List;
 
+import javax.transaction.Transactional;
+
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Modifying;
 import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
 
 import io.github.Hattinger04.course.model.student.Student;
@@ -13,6 +17,43 @@ public interface CourseRepository extends JpaRepository<Course, Long>{
 	Course findById(int id);
 	Course findByName(String name);
 	// TODO: SQL not tested yet!
-	@Query(value = "SELECT * FROM STUDENTS s JOIN USER u using(user_id) JOIN course c using(course_id, user_id) where c.course_id=:course_id", nativeQuery = true)
+	
+	@Query(value = "SELECT * FROM STUDENT s JOIN USER u using(user_id) JOIN course c using(course_id, user_id) where c.course_id=:course_id", nativeQuery = true)
 	List<Student> getAllStudents(int course_id); 
+	
+	@Modifying
+	@Query(value = "insert into user_course where user_id = :user_id and course_id=:course_id", nativeQuery = true)
+	@Transactional
+	public void addUserToCourse(@Param("user_id") int user_id, @Param("course_id") int course_id);
+	
+	@Modifying
+	@Query(value = "delete from user_course where user_id = :user_id and course_id=:course_id", nativeQuery = true)
+	@Transactional
+	public void removeUserFromCourse(@Param("user_id") int user_id, @Param("course_id") int course_id);
+	
+	@Query(value = "SELECT count(*) FROM STUDENT s JOIN USER u using(user_id) JOIN course c using(course_id, user_id) where c.course_id=:course_id", nativeQuery = true)
+	public int countStudents(@Param("course_id") int course_id); 
+
+	/**
+	 * If return value equals 0 => no student with this user_id exists
+	 * 
+	 * @param user_id
+	 * @param course_id
+	 * @return
+	 */
+	@Query(value = "SELECT count(*) FROM STUDENT s JOIN USER u using(user_id) JOIN course c using(course_id, user_id) where c.course_id=:course_id and s.user_id=:user_id", nativeQuery = true)
+	public int isUserStudent(@Param("user_id") int user_id, @Param("course_id") int course_id); 
+	
+	@Query(value = "SELECT count(*) FROM TEACHER t JOIN USER u using(user_id) JOIN course c using(course_id, user_id) where c.course_id=:course_id", nativeQuery = true)
+	public int countTeacher(@Param("course_id") int course_id); 
+	
+	/**
+	 * If return value equals 0 => no teacher with this user_id exists
+	 * 
+	 * @param user_id
+	 * @param course_id
+	 * @return
+	 */
+	@Query(value = "SELECT count(*) FROM TEACHER t JOIN USER u using(user_id) JOIN course c using(course_id, user_id) where c.course_id=:course_id and t.user_id=:user_id", nativeQuery = true)
+	public int isUserTeacher(@Param("user_id") int user_id, @Param("course_id") int course_id); 
 }

src/main/java/io/github/Hattinger04/course/model/teacher/Teacher.java

@@ -20,6 +20,7 @@
 @AllArgsConstructor
 @ToString
 public class Teacher {
+	
 	@Id
 	@GeneratedValue(strategy = GenerationType.IDENTITY)
 	@Column(name = "teacher_id")

src/main/java/io/github/Hattinger04/user/model/UserRepository.java

@@ -14,12 +14,15 @@
 public interface UserRepository extends JpaRepository<User, Long> {
 	User findById(int id);
 	User findByUsername(String username);
+	
 	@Query(value = "SELECT auto_increment FROM information_schema.tables WHERE table_name='users'", nativeQuery = true)
 	List<Long> getNextSeriesId();
+	
 	@Modifying
 	@Query(value = "Insert into user_role(user_id, role_id) VALUES (:user_id, :role_id)", nativeQuery = true)
 	@Transactional
 	public void insertUserRole(@Param("user_id") int user_id, @Param("role_id") int role_id); 
+	
 	@Modifying
 	@Query(value = "delete from user_role where user_id = :user_id and role_id=:role_id", nativeQuery = true)
 	@Transactional