Lab6 - done

Author: Wajktor13

lab05/command/build/classes/java/main/command/RemoveTransactionCommand.class

@@ -9,6 +9,9 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
+import java.util.stream.Collector;
+import java.util.stream.Collectors;
 
 @RestController
 @RequestMapping(path = "courses")
@@ -35,4 +38,14 @@ public List<Student> getAssignedStudents(@PathVariable String id) {
             throw new ResponseStatusException(HttpStatus.NOT_FOUND, "course not found");
         }
     }
+
+    @GetMapping(path = "{id}/allMean")
+    public Map<Student, Float> getMeanForAllStudents(@PathVariable String id) {
+        try {
+            Long idLong = Long.parseLong(id);
+            return this.courseService.getMeanForAllStudents(idLong);
+        } catch (NumberFormatException e) {
+            throw new ResponseStatusException(HttpStatus.NOT_FOUND, "course not found");
+        }
+    }
 }

lab06/school/school.mv.db

@@ -14,4 +14,11 @@ public interface CourseRepository extends JpaRepository<Course, Long> {
     @Query("SELECT s FROM Student s " +
             "WHERE s.id IN (SELECT student.id FROM Course c, IN(c.students) student WHERE c.id = :courseId)")
     List<Student> getAssignedStudents(@Param("courseId") Long courseId);
+
+    @Query(value = "SELECT STUDENT.ID, BIRTH_DATE, FIRST_NAME, INDEX_NUMBER, LAST_NAME, AVG(GRADE_VALUE) FROM STUDENT_GRADES \n" +
+            "JOIN STUDENT ON STUDENT.ID = STUDENT_GRADES.STUDENT_ID\n" +
+            "JOIN GRADE ON GRADE.ID = STUDENT_GRADES.GRADES_ID\n" +
+            "WHERE COURSE_ID = 4\n" +
+            "GROUP BY STUDENT.ID", nativeQuery = true)
+    List<List<Object>> getMeanForAllStudents(@Param("courseId") Long courseId);
 }

lab06/school/school.trace.db

@@ -2,18 +2,23 @@
 
 import org.springframework.stereotype.Service;
 import pl.edu.agh.to.school.student.Student;
+import pl.edu.agh.to.school.student.StudentRepository;
+import pl.edu.agh.to.school.student.StudentService;
 
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Optional;
+import java.math.BigDecimal;
+import java.math.BigInteger;
+import java.util.*;
 
 @Service
 public class CourseService {
 
     private final CourseRepository courseRepository;
 
-    public CourseService(CourseRepository courseRepository) {
+    private final StudentRepository studentRepository;
+
+    public CourseService(CourseRepository courseRepository, StudentRepository studentRepository) {
         this.courseRepository = courseRepository;
+        this.studentRepository = studentRepository;
     }
 
     public List<Course> getAllCourses() {
@@ -27,4 +32,20 @@ public List<Student> getAssignedStudents(Long courseId) {
     public Optional<Course> getCourseById(Long id) {
         return this.courseRepository.findById(id);
     }
+
+    public Map<Student, Float> getMeanForAllStudents(Long courseId) {
+        List<List<Object>> resultList = this.courseRepository.getMeanForAllStudents(courseId);
+        Student student;
+        Float meanGrade;
+        Map<Student, Float> meanGradesMap = new HashMap<>();
+
+        for (List<Object> innerResult : resultList) {
+            meanGrade = ((BigDecimal) innerResult.get(innerResult.size() - 1)).floatValue();
+            student = this.studentRepository.getReferenceById(((BigInteger) innerResult.get(0)).longValue());
+
+            meanGradesMap.put(student, meanGrade);
+        }
+
+        return meanGradesMap;
+    }
 }

lab06/school/src/main/java/pl/edu/agh/to/school/course/CourseController.java

@@ -18,7 +18,6 @@ public class StudentService {
 
     private final StudentRepository studentRepository;
     private final CourseService courseService;
-
     private final GradeService gradeService;
 
     public StudentService(StudentRepository studentRepository, CourseService courseService, GradeService gradeService) {
@@ -27,6 +26,10 @@ public StudentService(StudentRepository studentRepository, CourseService courseS
         this.gradeService = gradeService;
     }
 
+    public Student getStudentById(Long id) {
+        return this.studentRepository.getReferenceById(id);
+    }
+
     public List<Student> getStudents() {
         return studentRepository.findAll();
     }