Add package assignment1

.vscode/settings.json

@@ -1,7 +1,6 @@
 {
+    "java.project.explorer.showNonJavaResources": false,
     "java.project.referencedLibraries": [
-        "lib/**/*.jar",
+        "lib/**/*.jar"
-        "excel/jxl.jar"
+    ]
-    ],
-    "java.project.explorer.showNonJavaResources": false
 }

assignment1/Encrypt.java

@@ -0,0 +1,30 @@
+package assignment1;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+//对字符串进行加密
+public class Encrypt {
+	public static String MD5(String str) {
+		try {
+			MessageDigest md = MessageDigest.getInstance("MD5");
+			md.update(str.getBytes());
+			byte[] b = md.digest();
+			StringBuffer sb = new StringBuffer();
+			for (byte c : b) {
+				int val = ((int) c) & 0xff;
+				if (val < 16)
+					sb.append("0");
+				sb.append(Integer.toHexString(val));
+			}
+			return sb.toString().toUpperCase();
+		} catch (NoSuchAlgorithmException e) {
+			e.printStackTrace();
+		}
+		return null;
+	}
+
+	public static void main(String[] args) {
+		System.out.println(MD5("123456"));
+	}
+}

assignment1/PasswordChange.java

@@ -0,0 +1,91 @@
+package assignment1;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.Scanner;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class PasswordChange {
+    static final String DBURL = "jdbc:mysql://localhost:3306/xiaoshou?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT";
+
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        Connection conn = null;
+        PreparedStatement pstmt = null;
+        ResultSet rs = null;
+        try {
+            Class.forName("com.mysql.cj.jdbc.Driver");
+            conn = DriverManager.getConnection(DBURL);
+            System.out.print("请输入用户名：");
+            String username = scanner.nextLine();
+            String checkUserSql = "SELECT xingming FROM t_yong WHERE yonghuming=?";
+            pstmt = conn.prepareStatement(checkUserSql);
+            pstmt.setString(1, username);
+            rs = pstmt.executeQuery();
+            if (!rs.next()) {
+                System.out.println("该用户不存在，请重新输入");
+                return;
+            }
+            System.out.print("请输入当前用户的原密码：");
+            String oldPassword = scanner.nextLine();
+            String checkPasswordSql = "SELECT xingming FROM t_yong WHERE yonghuming=? AND mima=MD5(?)";
+            pstmt = conn.prepareStatement(checkPasswordSql);
+            pstmt.setString(1, username);
+            pstmt.setString(2, oldPassword);
+            rs = pstmt.executeQuery();
+            if (!rs.next()) {
+                System.out.println("原密码输入不正确，请重新输入");
+                return;
+            }
+            String newPassword;
+            while (true) {
+                System.out.print("请设置新的密码：");
+                newPassword = scanner.nextLine();
+                if (!isPasswordComplex(newPassword))
+                    System.out.println("您的密码不符合复杂性要求（密码长度不少于6个字符，至少有一个小写字母，至少有一个大写字母，至少一个数字），请重新输入：");
+                else
+                    break;
+            }
+            System.out.print("请输入确认密码：");
+            String confirmPassword = scanner.nextLine();
+            if (!newPassword.equals(confirmPassword)) {
+                System.out.println("两次输入的密码必须一致，请重新输入确认密码：");
+                return;
+            }
+            String updatePasswordSql = "UPDATE t_yong SET mima=? WHERE yonghuming=?";
+            pstmt = conn.prepareStatement(updatePasswordSql);
+            pstmt.setString(1, Encrypt.MD5(newPassword));
+            pstmt.setString(2, username);
+            int result = pstmt.executeUpdate();
+            if (result > 0)
+                System.out.println("您已成功修改密码，请谨记");
+            else
+                System.out.println("密码修改失败，请重试");
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            try {
+                if (rs != null)
+                    rs.close();
+                if (pstmt != null)
+                    pstmt.close();
+                if (conn != null)
+                    conn.close();
+            } catch (SQLException se) {
+                se.printStackTrace();
+            }
+        }
+    }
+
+    public static boolean isPasswordComplex(String password) {
+        if (password.length() < 6)
+            return false;
+        Pattern pattern = Pattern.compile("^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z]).{6,}$");
+        Matcher matcher = pattern.matcher(password);
+        return matcher.matches();
+    }
+}

assignment1/SupermarketManagement.java

@@ -0,0 +1,85 @@
+package assignment1;
+
+import java.math.BigDecimal;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.Scanner;
+
+public class SupermarketManagement {
+    private static final String DBURL = "jdbc:mysql://localhost:3306/xiaoshou?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT";
+
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        int choice;
+        try (Connection conn = DriverManager.getConnection(DBURL)) {
+            do {
+                System.out.println("===超市商品管理维护====");
+                System.out.println("1、输入商品");
+                System.out.println("2、查询商品");
+                System.out.println("3、退出");
+                System.out.print("请选择（1-3）：");
+                choice = scanner.nextInt();
+                scanner.nextLine();
+                switch (choice) {
+                    case 1:
+                        addProduct(scanner, conn);
+                        break;
+                    case 2:
+                        queryProduct(scanner, conn);
+                        break;
+                    case 3:
+                        System.out.println("退出系统");
+                        break;
+                    default:
+                        System.out.println("无效选择，请重新选择（1-3）：");
+                }
+            } while (choice != 3);
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+    }
+
+    private static void addProduct(Scanner scanner, Connection conn) throws SQLException {
+        System.out.print("请输入商品信息（格式：条形码，商品名称，单价，供应商）：");
+        String input = scanner.nextLine();
+        String[] productInfo = input.split("，");
+        String tiaoma = productInfo[0];
+        PreparedStatement checkStmt = conn.prepareStatement("SELECT COUNT(*) FROM t_shangping WHERE tiaoma = ?");
+        checkStmt.setString(1, tiaoma);
+        ResultSet rs = checkStmt.executeQuery();
+        rs.next();
+        if (rs.getInt(1) > 0) {
+            System.out.println("条形码不能重复，请重新输入");
+            return;
+        }
+        PreparedStatement insertStmt = conn.prepareStatement(
+                "INSERT INTO t_shangping (tiaoma, mingcheng, danjia, gongyingshang) VALUES (?, ?, ?, ?)");
+        insertStmt.setString(1, tiaoma);
+        insertStmt.setString(2, productInfo[1]);
+        insertStmt.setBigDecimal(3, new BigDecimal(productInfo[2]));
+        insertStmt.setString(4, productInfo[3]);
+        insertStmt.executeUpdate();
+        System.out.println("增加成功");
+    }
+
+    private static void queryProduct(Scanner scanner, Connection conn) throws SQLException {
+        System.out.print("请输入查询的商品名称：");
+        String nameQuery = scanner.nextLine();
+        PreparedStatement queryStmt = conn.prepareStatement("SELECT * FROM t_shangping WHERE mingcheng LIKE ?");
+        queryStmt.setString(1, "%" + nameQuery + "%");
+        ResultSet rs = queryStmt.executeQuery();
+        System.out.println("满足条件的记录总共" + rs.getFetchSize() + "条，信息如下：");
+        System.out.println("序号\t条形码\t商品名称\t单价\t供应商");
+        int count = 1;
+        while (rs.next()) {
+            System.out.println(count++ + "\t" +
+                    rs.getString("tiaoma") + "\t" +
+                    rs.getString("mingcheng") + "\t" +
+                    rs.getBigDecimal("danjia") + "\t" +
+                    rs.getString("gongyingshang"));
+        }
+    }
+}

assignment1/UserLogin.java

@@ -0,0 +1,66 @@
+package assignment1;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.Scanner;
+
+public class UserLogin {
+    static final String DBURL = "jdbc:mysql://localhost:3306/xiaoshou?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT";
+
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        Connection conn = null;
+        PreparedStatement pstmt = null;
+        ResultSet rs = null;
+        try {
+            Class.forName("com.mysql.cj.jdbc.Driver");
+            conn = DriverManager.getConnection(DBURL);
+            int attempts = 0;
+            boolean loginSuccess = false;
+            while (attempts < 3 && !loginSuccess) {
+                System.out.println("欢迎使用阳光超市收银系统，请登陆");
+                System.out.print("请输入用户名: ");
+                String username = scanner.nextLine();
+                System.out.print("请输入密码: ");
+                String password = scanner.nextLine();
+                String sql = "SELECT xingming FROM t_yong WHERE yonghuming=? AND mima=?";
+                pstmt = conn.prepareStatement(sql);
+                pstmt.setString(1, username);
+                pstmt.setString(2, Encrypt.MD5(password));
+                rs = pstmt.executeQuery();
+                if (rs.next()) {
+                    loginSuccess = true;
+                    String xingming = rs.getString("xingming");
+                    SimpleDateFormat formatter = new SimpleDateFormat("yyyy年MM月dd日HH时mm分ss秒");
+                    String currentTime = formatter.format(new Date());
+                    System.out.println("欢迎使用阳光超市收银系统");
+                    System.out.println("当前收银员：" + xingming);
+                    System.out.println("当前时间：" + currentTime);
+                } else {
+                    System.out.println("用户名或密码不正确，请重新输入");
+                    attempts++;
+                }
+            }
+            if (!loginSuccess)
+                System.out.println("最多只能尝试3次");
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            try {
+                if (rs != null)
+                    rs.close();
+                if (pstmt != null)
+                    pstmt.close();
+                if (conn != null)
+                    conn.close();
+            } catch (SQLException se) {
+                se.printStackTrace();
+            }
+        }
+    }
+}

assignment1/商品信息.txt

@@ -0,0 +1,9 @@
+商品条码	商品名称	单价	供应商
+=========================
+100001	手机	4500.00	华为
+100002	鼠标	61.00	华为
+300001	运动鞋	485	耐克
+300002	衬衣	270	雅戈尔
+300003	牛仔裤	156.5	啄木鸟
+400001	电冰箱	4500	海尔
+400002	电视机	6999	长虹		

assignment1/数据库脚本.sql

@@ -0,0 +1,77 @@
+/*
+Navicat MySQL Data Transfer
+
+Source Server         : localhost_3306
+Source Server Version : 80032
+Source Host           : localhost:3306
+Source Database       : xiaoshou
+
+Target Server Type    : MYSQL
+Target Server Version : 80032
+File Encoding         : 65001
+
+Date: 2023-05-11 10:27:07
+*/
+
+SET FOREIGN_KEY_CHECKS=0;
+
+-- ----------------------------
+-- Table structure for t_shangping
+-- ----------------------------
+DROP TABLE IF EXISTS `t_shangping`;
+CREATE TABLE `t_shangping` (
+  `tiaoma` varchar(255) NOT NULL,
+  `mingcheng` varchar(255) DEFAULT NULL,
+  `danjia` decimal(10,2) DEFAULT NULL,
+  `gongyingshang` varchar(255) DEFAULT NULL,
+  PRIMARY KEY (`tiaoma`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
+
+-- ----------------------------
+-- Records of t_shangping
+-- ----------------------------
+INSERT INTO `t_shangping` VALUES ('100001', '手机', '4500.00', '华为');
+INSERT INTO `t_shangping` VALUES ('100002', '鼠标', '61.00', '华为');
+INSERT INTO `t_shangping` VALUES ('100003', '矿泉水', '2.50', '农夫山泉');
+INSERT INTO `t_shangping` VALUES ('100004', '香烟', '20.00', '武汉卷烟厂');
+INSERT INTO `t_shangping` VALUES ('100005', '牙膏', '4.50', '中华牙膏厂');
+INSERT INTO `t_shangping` VALUES ('200001', '电脑', '4300.00', 'dell');
+INSERT INTO `t_shangping` VALUES ('200002', '小明同学', '5.50', '武汉饮料集团');
+
+-- ----------------------------
+-- Table structure for t_shouyinmingxi
+-- ----------------------------
+DROP TABLE IF EXISTS `t_shouyinmingxi`;
+CREATE TABLE `t_shouyinmingxi` (
+  `liushuihao` varchar(255) NOT NULL,
+  `tiaoma` varchar(255) DEFAULT NULL,
+  `mingcheng` varchar(255) DEFAULT NULL,
+  `danjia` decimal(10,0) DEFAULT NULL,
+  `shuliang` int DEFAULT NULL,
+  `shouyinyuan` varchar(255) DEFAULT NULL,
+  `xiaoshoushijian` datetime DEFAULT NULL,
+  PRIMARY KEY (`liushuihao`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
+
+-- ----------------------------
+-- Records of t_shouyinmingxi
+-- ----------------------------
+
+-- ----------------------------
+-- Table structure for t_yonghu
+-- ----------------------------
+DROP TABLE IF EXISTS `t_yonghu`;
+CREATE TABLE `t_yonghu` (
+  `yonghuming` varchar(255) NOT NULL,
+  `mima` varchar(255) DEFAULT NULL,
+  `xingming` varchar(255) DEFAULT NULL,
+  `juese` varchar(255) DEFAULT NULL,
+  PRIMARY KEY (`yonghuming`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
+
+-- ----------------------------
+-- Records of t_yonghu
+-- ----------------------------
+INSERT INTO `t_yonghu` VALUES ('niegang', null, '聂刚', '管理员');
+INSERT INTO `t_yonghu` VALUES ('wangyuxin', null, '王玉欣', '收银员');
+INSERT INTO `t_yonghu` VALUES ('xiaowang', null, '小王', '收银员');