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| /*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package school.database;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
public class DatabaseDAO {
private static final String URL = "jdbc:mysql://localhost:3306/school_db?useTimezone=true&serverTimezone=GMT";
private static final String USER = "root";
private static final String PASSWORD = "123456";
private static final String GET_ALL_CLASSES_QUERY =
"SELECT id, name FROM class ORDER BY name";
private static final String GET_STUDENTS_IN_CLASS_QUERY =
"SELECT * FROM student WHERE class_id = ?";
private static final String GET_STUDENT_GRADES_QUERY =
"SELECT s.name, gv.values, g.grade_date, t.fullname\n" +
"FROM grade g JOIN subject s\n" +
"ON g.subject_id = s.id\n" +
"JOIN student st\n" +
"ON g.student_id = st.id\n" +
"JOIN grade_value gv\n" +
"ON g.grade_id = gv.id\n" +
"JOIN teacher t\n" +
"ON g.teacher_id = t.id\n" +
"WHERE st.id = ?";
private static final String INSERT_CLASS_QUERY = "INSERT INTO class (name) VALUES (?)";
private static final String DELETE_CLASS_QUERY = "DELETE FROM class WHERE id = ?;";
private static final String INSERT_STUDENT_QUERY =
"INSERT INTO student\n" +
"(class_id, name, surname, birthday, phone)\n" +
"VALUES(?, ?, ?, ?, ?);";
public static final String DELETE_STUDENT_QUERY = "DELETE FROM student WHERE id = ?;";
private static final String GET_GRADE_VALUES_QUERY = "SELECT * FROM grade_value ORDER BY `values`;";
private static final String GET_SUBJECTS_FOR_CLASS_QUERY =
"SELECT s.name\n" +
"FROM subject s\n" +
"JOIN class_subject_connection csc\n" +
"ON csc.subject_id = s.id\n" +
"WHERE csc.class_id = ?\n" +
"ORDER BY s.name";
public static final String INSERT_GRADE_QUERY =
"INSERT INTO grade\n" +
"(grade_id, subject_id, teacher_id, student_id, grade_date)\n" +
"VALUES\n" +
"((SELECT id FROM grade_value WHERE `values` = ?),\n" +
" (SELECT id FROM subject WHERE name = ?),\n" +
" (SELECT id FROM teacher WHERE fullname = ?),\n" +
" ?, ?);";
private static final String GET_TEACHERS_FOR_SUBJECT_QUERY =
"SELECT t.fullname\n" +
"FROM teacher t\n" +
"JOIN teacher_subject_connection tsc\n" +
"ON tsc.teacher_id = t.id\n" +
"WHERE tsc.subject_id = \n" +
"(SELECT s.id\n" +
" FROM subject s\n" +
" WHERE s.name = ?)";
private Connection conn;
public DatabaseDAO() {
try {
conn = DriverManager.getConnection(URL, USER, PASSWORD);
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
public ArrayList<SchoolClass> readAllClassesFromDB() {
ArrayList<SchoolClass> result = new ArrayList<>();
try (PreparedStatement stmt = conn.prepareStatement(GET_ALL_CLASSES_QUERY)) {
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
int id = rs.getInt("id");
String name = rs.getString("name");
SchoolClass schoolClass = new SchoolClass(id, name);
result.add(schoolClass);
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
return result;
}
public ArrayList<Student> readStudentsInClassFromDB(int classID) {
ArrayList<Student> result = new ArrayList<>();
try (PreparedStatement stmt = conn.prepareStatement(GET_STUDENTS_IN_CLASS_QUERY)) {
stmt.setInt(1, classID);
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
int studentID = rs.getInt("id");
String firstName = rs.getString("name");
String lastName = rs.getString("surname");
Date birthday = rs.getDate("birthday");
Student student = new Student(studentID, firstName, lastName, "PATRON", birthday);
result.add(student);
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
return result;
}
public ArrayList<Grade> readGradesFromDB(int studentID) {
ArrayList<Grade> result = new ArrayList<>();
try (PreparedStatement stmt = conn.prepareStatement(GET_STUDENT_GRADES_QUERY)) {
stmt.setInt(1, studentID);
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
String subject = rs.getString("name");
int value = rs.getInt("values");
java.util.Date date = rs.getDate("grade_date");
String teacher = rs.getString("fullname");
Grade grade = new Grade(subject, teacher, value, date);
result.add(grade);
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
return result;
}
public void insertClassIntoDB(SchoolClass schoolClass) {
try (PreparedStatement stmt =
conn.prepareStatement(INSERT_CLASS_QUERY, Statement.RETURN_GENERATED_KEYS)) {
stmt.setString(1, String.valueOf(schoolClass.getNumber()) + schoolClass.getLetter());
stmt.executeUpdate();
ResultSet keys = stmt.getGeneratedKeys();
if (keys.next()) {
schoolClass.setId(keys.getInt(1));
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
public void deleteClassFromDB(SchoolClass schoolClass) {
try (PreparedStatement stmt = conn.prepareStatement(DELETE_CLASS_QUERY)) {
stmt.setInt(1, schoolClass.getId());
int rowsAffected = stmt.executeUpdate();
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
public void insertStudentIntoDB(Student student, SchoolClass schoolClass) {
try (PreparedStatement stmt =
conn.prepareStatement(INSERT_STUDENT_QUERY, Statement.RETURN_GENERATED_KEYS)) {
stmt.setInt(1, schoolClass.getId());
stmt.setString(2, student.getName());
stmt.setString(3, student.getSurname());
stmt.setDate(4, new Date(student.getBirthDate().getTime()));
stmt.setString(5, null);
stmt.executeUpdate();
ResultSet keys = stmt.getGeneratedKeys();
if (keys.next()) {
student.setId(keys.getInt(1));
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
public void deleteStudentFromDB(Student student) {
try (PreparedStatement stmt = conn.prepareStatement(DELETE_STUDENT_QUERY)) {
stmt.setInt(1, student.getId());
int rowsAffected = stmt.executeUpdate();
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
public List<Integer> readGradeValuesFromDB() {
List<Integer> result = new ArrayList<>();
try (PreparedStatement stmt = conn.prepareStatement(GET_GRADE_VALUES_QUERY)) {
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
int value = rs.getInt("values");
result.add(value);
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
return result;
}
public List<String> readSubjectsForClassFromDB(SchoolClass schoolClass) {
List<String> result = new ArrayList<>();
try (PreparedStatement stmt = conn.prepareStatement(GET_SUBJECTS_FOR_CLASS_QUERY)) {
stmt.setInt(1, schoolClass.getId());
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
String name = rs.getString("name");
result.add(name);
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
return result;
}
public void insertGradeIntoDB(Student student, Grade grade) {
try (PreparedStatement stmt =
conn.prepareStatement(INSERT_GRADE_QUERY, Statement.RETURN_GENERATED_KEYS)) {
stmt.setInt(1, grade.getValue());
stmt.setString(2, grade.getSubject());
stmt.setString(3, grade.getTeacher());
stmt.setInt(4, student.getId());
stmt.setDate(5, new Date(grade.getDate().getTime()));
stmt.executeUpdate();
ResultSet keys = stmt.getGeneratedKeys();
if (keys.next()) {
grade.setId(keys.getInt(1));
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
public List<String> readTeachersForSubjectFromDB(String subject) {
List<String> result = new ArrayList<>();
try (PreparedStatement stmt = conn.prepareStatement(GET_TEACHERS_FOR_SUBJECT_QUERY)) {
stmt.setString(1, subject);
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
String fullname = rs.getString("fullname");
result.add(fullname);
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
return result;
}
} |
(
