这是否正确实现了：事务、DBCP 和嵌套的 try-with-resources？

Question

我只是想知道这是否是所有事情的良好实施？ 我已经实现了多线程系统，所以每个线程都有自己的连接。

这里是更多上下文的代码：

package dao;

import dao.jdbc.DatabaseConnection;
import dao.contracts.AdminContract;
import dao.dto.Account;
import dao.dto.AccountBuilder;
import dao.dto.Director;
import java.sql.PreparedStatement;
import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.ArrayList;

/**
 *
 * @author Milos
 */
public class AdminAccess implements AdminContract {

        @Override
    public boolean addAccount(Account account) {
        try ( Connection con = DatabaseConnection.getConnection()) {
            String addAccountQuery = "INSERT INTO account (username_email, password, account_type) VALUES(?, ?, ?);";

            String addAdminQuery = "INSERT INTO admin (admin_id, first_name, last_name, email, phone_number, god_id) VALUES(?, ?, ?, ?, ?, ?);";

            String addInstructorQuery = "INSERT INTO instructor (instructor_id, first_name, last_name, initials, birthdate, gender, phone_number, admin_id) VALUES(?, ?, ?, ?, ?, ?, ?, ?);";

            String addStudentQuery = "INSERT INTO student (student_id, first_name, last_name, city, street, postal_code, birthdate, gender, instructor_id, admin_id) VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?);";

            con.setAutoCommit(false);
            try ( PreparedStatement addAccount = con.prepareStatement(addAccountQuery, Statement.RETURN_GENERATED_KEYS);  PreparedStatement addAdmin = con.prepareStatement(addAdminQuery);  PreparedStatement addInstructor = con.prepareStatement(addInstructorQuery);  
PreparedStatement addStudent = con.prepareStatement(addStudentQuery)) {

                switch (account.getAccountType()) {
                    case 'A' -> {
                        addAccount.setString(1, account.getUsernameEmail());
                        addAccount.setString(2, account.getPassword());
                        addAccount.setString(3, String.valueOf(account.getAccountType()));
                        addAccount.executeUpdate();
                        try ( ResultSet rs = addAccount.getGeneratedKeys()) {
                            rs.next();
                            addAdmin.setInt(1, rs.getInt(1));
                            addAdmin.setString(2, account.getFirstName());
                            addAdmin.setString(3, account.getLastName());
                            addAdmin.setString(4, account.getEmail());
                            addAdmin.setString(5, account.getPhoneNumber());
                            addAdmin.setInt(6, account.getGodId());
                            addAdmin.executeUpdate();
                        }
                        con.commit();
                    }
                    case 'I' -> {
                        addAccount.setString(1, account.getUsernameEmail());
                        addAccount.setString(2, account.getPassword());
                        addAccount.setString(3, String.valueOf(account.getAccountType()));
                        addAccount.executeUpdate();
                        try ( ResultSet rs = addAccount.getGeneratedKeys()) {
                            rs.next();
                            addInstructor.setInt(1, rs.getInt(1));
                            addInstructor.setString(2, account.getFirstName());
                            addInstructor.setString(3, account.getLastName());
                            addInstructor.setString(4, account.getInitials());
                            addInstructor.setString(5, account.getBirthDate());
                            addInstructor.setString(6, String.valueOf(account.getGender()));
                            addInstructor.setString(7, account.getPhoneNumber());
                            addInstructor.setInt(8, account.getAdminId());
                            addInstructor.executeUpdate();
                        }
                        con.commit();
                    }
                    case 'S' -> {
                        addAccount.setString(1, account.getUsernameEmail());
                        addAccount.setString(2, account.getPassword());
                        addAccount.setString(3, String.valueOf(account.getAccountType()));
                        addAccount.executeUpdate();
                        try ( ResultSet rs = addAccount.getGeneratedKeys()) {
                            rs.next();
                            addStudent.setInt(1, rs.getInt(1));
                            addStudent.setString(2, account.getFirstName());
                            addStudent.setString(3, account.getLastName());
                            addStudent.setString(4, account.getCity());
                            addStudent.setString(5, account.getStreet());
                            addStudent.setInt(6, account.getPostalCode());
                            addStudent.setString(7, account.getBirthDate());
                            addStudent.setString(8, String.valueOf(account.getGender()));
                            addStudent.setInt(9, account.getInstructorId());
                            addStudent.setInt(10, account.getAdminId());
                            addStudent.executeUpdate();
                        }
                        con.commit();
                    }
                }
            } catch (SQLException ex) {
                System.out.println(ex.getLocalizedMessage());
                System.out.println("Insert is being rolled back!");
                con.rollback();
                return false;
            }
        } catch (SQLException ex) {
            System.out.println(ex.getLocalizedMessage());
            return false;
        }
        return true;
    }
}

package dao.jdbc;

import org.apache.commons.dbcp2.BasicDataSource;
import java.sql.Connection;
import java.sql.SQLException;

/**
 *
 * @author Milos
 */
public class DatabaseConnection {

    private static final String DRIVER = "com.mysql.cj.jdbc.Driver";
    private static final String URL = "jdbc:mysql://localhost:3306/mydatabase";
    private static final String USERNAME = "root";
    private static final String PASSWORD = "password";
    private static final BasicDataSource DATA_SOURCE;

    static {
        DATA_SOURCE = new BasicDataSource();
        DATA_SOURCE.setDriverClassName(DRIVER);
        DATA_SOURCE.setUrl(URL);
        DATA_SOURCE.setUsername(USERNAME);
        DATA_SOURCE.setPassword(PASSWORD);
    }

    private DatabaseConnection() {
    }

    public static Connection getConnection() throws SQLException {
        return DATA_SOURCE.getConnection();
    }
}

一切正常，我测试了几次，但代码似乎有点乱。 有没有办法改进它？