package 学生成绩查询管理系统.JDBC; import javax.swing.*; import java.sql.*; public class JDBCUtils { private static Connection conn; private static Statement stmt; private static final String drivername = "com.mysql.cj.jdbc.Driver"; private static final String Url = "jdbc:mysql://localhost:3306/studentmanager"; private static final String username = "root"; private static final String password = "123456"; static { try { Class.forName(drivername); } catch (ClassNotFoundException e) { JOptionPane.showMessageDialog(null, "加载数据库驱动出错,请查明原因!"); } try { conn = DriverManager.getConnection(Url, username, password); stmt = conn.createStatement(); } catch (SQLException e) { JOptionPane.showMessageDialog(null, "数据库驱动出错,用户名或密码错误!"); } } public boolean admincheckLogin(String useraccount, String userpassword) { Connection connection = null; PreparedStatement statement = null; ResultSet resultSet = null; try { // 创建数据库连接 connection = DriverManager.getConnection(Url, username, password); // 编写SQL查询语句 String sql = "SELECT * FROM userdatabases WHERE account = ? AND password = ?"; // 创建预编译的语句对象 statement = connection.prepareStatement(sql); // 设置参数 statement.setString(1, useraccount); statement.setString(2, userpassword); // 执行查询并获取结果集 resultSet = statement.executeQuery(); // 返回是否存在匹配的记录 return resultSet.next(); } catch (SQLException e) { e.printStackTrace(); } finally { // 关闭数据库资源 try { if (resultSet != null) { resultSet.close(); } if (statement != null) { statement.close(); } if (connection != null) { connection.close(); } } catch (SQLException e) { e.printStackTrace(); } } return false; // 出现异常或查询失败时返回false } public boolean teachercheckLogin(String useraccount, String userpassword) { Connection connection = null; PreparedStatement statement = null; ResultSet resultSet = null; try { // 创建数据库连接 connection = DriverManager.getConnection(Url, username, password); // 编写SQL查询语句 String sql = "SELECT * FROM teacheraccount WHERE account = ? AND password = ?"; // 创建预编译的语句对象 statement = connection.prepareStatement(sql); // 设置参数 statement.setString(1, useraccount); statement.setString(2, userpassword); // 执行查询并获取结果集 resultSet = statement.executeQuery(); // 返回是否存在匹配的记录 return resultSet.next(); } catch (SQLException e) { e.printStackTrace(); } finally { // 关闭数据库资源 try { if (resultSet != null) { resultSet.close(); } if (statement != null) { statement.close(); } if (connection != null) { connection.close(); } } catch (SQLException e) { e.printStackTrace(); } } return false; // 出现异常或查询失败时返回false } public boolean studentcheckLogin(String useraccount, String userpassword) { Connection connection = null; PreparedStatement statement = null; ResultSet resultSet = null; try { // 创建数据库连接 connection = DriverManager.getConnection(Url, username, password); // 编写SQL查询语句 String sql = "SELECT * FROM studentaccount WHERE account = ? AND password = ?"; // 创建预编译的语句对象 statement = connection.prepareStatement(sql); // 设置参数 statement.setString(1, useraccount); statement.setString(2, userpassword); // 执行查询并获取结果集 resultSet = statement.executeQuery(); // 返回是否存在匹配的记录 return resultSet.next(); } catch (SQLException e) { e.printStackTrace(); } finally { // 关闭数据库资源 try { if (resultSet != null) { resultSet.close(); } if (statement != null) { statement.close(); } if (connection != null) { connection.close(); } } catch (SQLException e) { e.printStackTrace(); } } return false; // 出现异常或查询失败时返回false } }