javaEE数据库和struts2结合(实现一个简单的商店系统,以Mysql或access数据库为例,)

package user; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; public class userdao { private static final String DB_URL = "jdbc:mysql://localhost:3306/dh?useUnicode=true&characterEncoding=utf8"; private static final String DB_USER = "root"; private static final String DB_PASSWORD = "111111"; public boolean validateUser(long id, long password) { Connection conn = null; PreparedStatement stmt = null; ResultSet rs = null; boolean isValidUser = false; try { Class.forName("com.mysql.jdbc.Driver"); System.out.println("Connecting to database..."); conn = DriverManager.getConnection(DB_URL, DB_USER, DB_PASSWORD); System.out.println("Database connection successful!"); String sql = "SELECT * FROM user WHERE Id = ? AND Password = ?"; System.out.printf("Received id: %d%n", id); System.out.printf("Received password: %d%n", password); stmt = conn.prepareStatement(sql); stmt.setLong(1, id); stmt.setLong(2, password); rs = stmt.executeQuery(); if (rs.next()) { isValidUser = true; } } catch (Exception e) { e.printStackTrace(); System.err.println("Error: " + e.getMessage()); // 输出错误信息 } finally { // 关闭数据库资源 try { if (rs != null) { rs.close(); } if (stmt != null) { stmt.close(); } if (conn != null) { conn.close(); } } catch (Exception e) { e.printStackTrace(); System.err.println("Error: " + e.getMessage()); // 输出错误信息 } } System.out.println("isValidUser: " + isValidUser); // 添加调试信息 return isValidUser; } public boolean insertUser(User user) { Connection conn = null; PreparedStatement stmt = null; try { Class.forName("com.mysql.jdbc.Driver"); System.out.println("Connecting to database..."); conn = DriverManager.getConnection(DB_URL, DB_USER, DB_PASSWORD); System.out.println("Database connection successful!"); String sql = "INSERT INTO user (Id, Pname, Gender, Level, VIP, Money, Password) VALUES (?, ?, ?, ?, ?, ?, ?)"; stmt = conn.prepareStatement(sql); stmt.setLong(1, user.getId()); stmt.setString(2, user.getPname()); stmt.setString(3, user.getGender()); stmt.setInt(4, user.getLevel()); stmt.setString(5, user.getVip()); stmt.setFloat(6, user.getMoney()); stmt.setLong(7, user.getPassword()); int rowsAffected = stmt.executeUpdate(); System.out.println("Rows affected: " + rowsAffected); // 添加调试信息 return rowsAffected > 0; } catch (Exception e) { e.printStackTrace(); System.err.println("Error: " + e.getMessage()); // 输出错误信息 return false; } finally { // 关闭数据库资源 try { if (stmt != null) { stmt.close(); } if (conn != null) { conn.close(); } } catch (Exception e) { e.printStackTrace(); System.err.println("Error: " + e.getMessage()); // 输出错误信息 } } } }