/*
 Navicat Premium Data Transfer
 Source Server         : root
 Source Server Type    : MySQL
 Source Server Version : 80026
 Source Host           : localhost:3306
 Source Schema         : javaweb
 Target Server Type    : MySQL
 Target Server Version : 80026
 File Encoding         : 65001
 Date: 07/09/2022 20:52:25
*/
SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
-- ----------------------------
-- Table structure for user
-- ----------------------------
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user`  (
  `id` int NOT NULL,
  `name` varchar(11) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL,
  `password` varchar(11) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL,
  `SEX` varchar(4) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL,
  `age` int NULL DEFAULT NULL,
  `brithday` datetime NULL DEFAULT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = Dynamic;
-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES (1, 'sunming', '123456', '男', 18, '2022-09-07 00:00:00');
SET FOREIGN_KEY_CHECKS = 1;

package util;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class DBConnection {
  private static final String driverName = "com.mysql.cj.jdbc.Driver";
  private static final String url = "jdbc:mysql://localhost:3306/testDB?"
    + "characterEncoding=utf8&useSSL=false&serverTimezone=UTC"
    + "&rewriteBatchedStatements=true";
  private static final String user = "root";
  private static final String password = "root";
  private DBConnection() {
  }
  static {
  try {
    Class.forName(driverName);
  } catch (ClassNotFoundException e) {
    e.printStackTrace();
  }
  }
  public static Connection getConnection() throws SQLException {
  return DriverManager.getConnection(url, user, password);
  }
  public static void close(ResultSet rs, Statement st, Connection conn) {
  try {
    if (rs != null) {
    rs.close();
    }
  } catch (SQLException e) {
    e.printStackTrace();
  } finally {
    try {
    if (st != null) {
      st.close();
    }
    } catch (SQLException e) {
    e.printStackTrace();
    } finally {
    if (conn != null) {
      try {
      conn.close();
      } catch (SQLException e) {
      e.printStackTrace();
      }
    }
    }
  }
  }
}

package jdbc;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import util.DBConnection;
public class UserLogin {
  public static boolean validlogin(String name, String password)throws SQLException{
  Connection conn = null;
  Statement st = null;
  ResultSet rs = null;
  boolean successflag=false;
  try {
    // 2、获得连接对象
    conn = DBConnection.getConnection();
    // 定义sql语句
    String sql = "select * from user where name='"+name+"' and password='"+password+"'";
    // 3、创建语句对象
    st = conn.createStatement();
    // 4、遍历结果集（此处不需要）
    rs=st.executeQuery(sql);
    if(rs.next()==true) successflag=true;
  } finally {
    // 5、关闭资源对象
    DBConnection.close(rs, st, conn);
  }
  return successflag;
  }
}