diff --git "a/work/com/java/minxi/java_20240515/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/MapDemo.java" "b/work/com/java/minxi/java_20240515/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/MapDemo.java"
new file mode 100644
index 0000000000000000000000000000000000000000..18bec7ee654ded4a5edce4ab37a3dc7df993afdb
--- /dev/null
+++ "b/work/com/java/minxi/java_20240515/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/MapDemo.java"
@@ -0,0 +1,62 @@
+package com.java.minxi.java_20240515.java_2302_刘宗旭_2344310210;
+
+import java.util.*;
+
+class Person{}
+
+public class MapDemo {
+    public static void main(String[] args) {
+        // 创建一个HashMap对象
+        HashMap<String, Integer> map = new HashMap<>();
+
+        // 添加键值对到HashMap中
+        map.put("凤凰院凶真", 18);
+        map.put("牧濑红莉栖", 18);
+        map.put("稚名真由里", 16);
+
+        // 使用键来获取对应的值，并打印出来。
+        Set<String> MapKey = map.keySet();
+        for (String s : MapKey)
+            System.out.println(s + " : " + map.get(s));
+        System.out.println();
+
+        // 检查一个键是否存在于HashMap中
+        System.out.println("Bob exists: " + map.containsKey("Bob"));
+
+        // 遍历所有的键
+        System.out.print("Iteration key：");
+        for (String key : map.keySet())
+            System.out.print(key + " ");
+        System.out.println();
+
+        // 遍历所有的值
+        System.out.print("Iteration value：");
+        for (Integer value : map.values())
+            System.out.print(value + " ");
+        System.out.println();
+
+        // 遍历所有的键值对
+        for (Map.Entry<String, Integer> entry : map.entrySet())
+            System.out.println(entry.getKey() + " : " + entry.getValue());
+
+        // 检查HashMap是否包含特定的键
+        System.out.println("HashMap contains Alice: " + map.containsKey("Alice"));
+
+        // 对一个已存在的键更新其对应的值
+        map.put("Alice", 26);
+        System.out.println("Alice's new age: " + map.get("Alice"));
+
+        // 移除一个特定的键值对，并确认它已被移除
+        map.remove("Bob");
+        System.out.println("Bob exists after removal: " + map.containsKey("Bob"));
+
+        // 获取Map的大小
+        System.out.println("Map size: " + map.size());
+
+        // 创建一个泛型 `HashMap`，键为自定义对象，值为字符串，并添加键值对
+        HashMap<Person, String> personMap = new HashMap<>();
+        Person p = new Person();
+        personMap.put(p, "阿万音铃羽");
+        System.out.println("Person map value: " + personMap.get(p));
+    }
+}
diff --git "a/work/com/java/minxi/java_20240515/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/SetDemo.java" "b/work/com/java/minxi/java_20240515/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/SetDemo.java"
new file mode 100644
index 0000000000000000000000000000000000000000..ec45a1c76d37f267b1870aae3ea8a7147f491a05
--- /dev/null
+++ "b/work/com/java/minxi/java_20240515/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/SetDemo.java"
@@ -0,0 +1,53 @@
+package com.java.minxi.java_20240515.java_2302_刘宗旭_2344310210;
+
+import java.util.*;
+
+public class SetDemo {
+    public static void main(String[] args) {
+        Set<String> set = new HashSet<>();//创建HashSet实例
+        set.add("Shanghai");
+        set.add("Beijing");
+        set.add("Jiangsu");
+        set.add("Nanjing");
+        set.add("Zhejiang");
+
+        Set<String> set2 = new HashSet<>();//创建HashSet实例
+        set2.add("Fujian");
+        set2.add("Taiwan");
+        set2.add("Henan");
+        set2.add("Hebei");
+        set2.add("Guangdong");
+
+        //元素检查
+        System.out.println("集合中是否包含'Shanghai'：" + set.contains("Shanghai"));
+        //元素移除
+        System.out.println(set.remove("Nanjing") + " " + set);
+        //集合大小
+        System.out.println("集合大小：" + set.size());
+
+        //迭代
+        System.out.print("迭代输出集合元素：");
+        for (String str : set) {
+            System.out.print(" " + str);
+        }
+        System.out.println();
+
+        //集合转换为数组
+        System.out.print("集合转换为数组：");
+        String[] s = set.toArray(new String[0]);
+        System.out.println(Arrays.toString(s));
+
+        //集合的并、交、差运算
+        //集合的并集
+        System.out.print(set.addAll(set2) + " ");
+        System.out.println(set);
+
+        //集合的交集
+        System.out.print(set.retainAll(set2) + " ");
+        System.out.println(set);
+
+        //集合的差集
+        System.out.print(set.removeAll(set2) + " ");
+        System.out.println(set);
+    }
+}
diff --git "a/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/BigDecimalDemo.java" "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/BigDecimalDemo.java"
new file mode 100644
index 0000000000000000000000000000000000000000..33c99ef597a4777b787bb8ab63f75f11cffde38a
--- /dev/null
+++ "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/BigDecimalDemo.java"
@@ -0,0 +1,41 @@
+package com.java.minxi.java_20240516.java_2302_刘宗旭_2344310210;
+
+import java.math.BigDecimal;
+import java.math.RoundingMode;
+
+public class BigDecimalDemo {
+    //加减乘除运算操作方法
+    public static String operation(BigDecimal number1, BigDecimal number2) {
+        BigDecimal sum = number1.add(number2);
+        BigDecimal different = number1.subtract(number2);
+        BigDecimal product = number1.multiply(number2);
+        BigDecimal quotient = number1.divide(number2, 20, RoundingMode.HALF_UP);
+        return "加法结果：" + sum + "\n减法结果：" + different + "\n乘法结果：" + product + "\n除法结果：" + quotient;
+    }
+
+    public static void main(String[] args) {
+        //使用字符串构造函数创建一个 `BigDecimal` 对象
+        BigDecimal bd1 = new BigDecimal("10.1");
+        System.out.println(bd1);
+
+        //使用valueOf()方法创建一个 `BigDecimal` 对象
+        BigDecimal bd2 = BigDecimal.valueOf(10.2);
+        System.out.println(bd2);
+
+        //基本算数运算
+        System.out.println(operation(bd1, bd2));
+
+        //四舍五入
+        BigDecimal rounded = bd1.setScale(2, RoundingMode.HALF_UP);
+        System.out.println("四舍五入：" + rounded);
+
+        //比较大小
+        int compareResult = bd1.compareTo(bd2);
+        if (compareResult > 0) {
+            System.out.println(bd1 + " 大于 " + bd2);
+        }else if (compareResult < 0) {
+            System.out.println(bd1 + " 小于 " + bd2);
+        }else
+            System.out.println(bd1 + " 等于 " + bd2);
+    }
+}
diff --git "a/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/DateDemo.java" "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/DateDemo.java"
new file mode 100644
index 0000000000000000000000000000000000000000..19cd6874abd97c8e510083d4971d9468cbf0e678
--- /dev/null
+++ "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/DateDemo.java"
@@ -0,0 +1,71 @@
+package com.java.minxi.java_20240516.java_2302_刘宗旭_2344310210;
+
+import java.text.*;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.GregorianCalendar;
+
+public class DateDemo {
+    //获取当前时间方法
+    public static Date getCurrentDate() {
+        return new Date();
+    }
+
+    //获取Date对象的年月日
+    public static void getDate(Date date) throws IllegalArgumentException {
+        Calendar calendar = new GregorianCalendar();
+        calendar.setTime(date);
+        int year = calendar.get(Calendar.YEAR);
+        int month = calendar.get(Calendar.MONTH) + 1; // 月份从0开始，所以需要加1
+        int day = calendar.get(Calendar.DAY_OF_MONTH);
+
+        System.out.println("年: " + year + ", 月: " + month + ", 日: " + day);
+    }
+
+    // 定义日期格式方法
+    public static String dateFormat(String pattern,Date date) {
+        SimpleDateFormat sdf = new SimpleDateFormat(pattern);
+        return sdf.format(date);
+    }
+
+    // 解析日期字符串方法
+    public static Date dateParse(String pattern, String dateString) throws ParseException {
+        SimpleDateFormat sdf = new SimpleDateFormat(pattern);
+        return sdf.parse(dateString);
+    }
+
+    public static void main(String[] args) {
+        // 获取当前时间
+        Date currentDate = getCurrentDate();
+        System.out.println("当前时间: " + currentDate);
+
+        // 获取年月日
+        try {
+            getDate(currentDate);
+        }catch(IllegalArgumentException e) {
+            System.out.println("输入的日期格式不正确");
+        }
+
+        // 格式化日期（Date转String）
+        String formattedDate = dateFormat("yyyy-MM-dd HH:mm:ss:SS", currentDate);
+        System.out.println("格式化后的日期为：" + formattedDate);
+
+        // 解析日期字符串（String转Date）
+        String dateString = "2023-05-16 12:30:45:789";
+        Date parsedDate;
+        try {
+            parsedDate = dateParse("yyyy-MM-dd HH:mm:ss", dateString);
+            System.out.println("解析后的日期为：" + parsedDate);
+        }catch (ParseException e) {
+            System.out.println("日期字符串格式不正确");
+        }
+
+        // 用System类获取时间戳
+        long timestamp = System.currentTimeMillis();
+        System.out.println("时间戳为：" + timestamp);
+
+        // 将时间戳转换为Date对象
+        Date timestampDate = new Date(timestamp);
+        System.out.println("时间戳转换的日期为：" + timestampDate);
+    }
+}
diff --git "a/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/MathDemo.java" "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/MathDemo.java"
new file mode 100644
index 0000000000000000000000000000000000000000..cbb337ca5dc736679391582c528198cff9a55ab7
--- /dev/null
+++ "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/MathDemo.java"
@@ -0,0 +1,107 @@
+package com.java.minxi.java_20240516.java_2302_刘宗旭_2344310210;
+
+import java.util.*;
+
+public class MathDemo {
+    // 取绝对值方法
+    public static double abs(double num) {
+        return Math.abs(num);
+    }
+
+    // 将字符串转换为数字
+    private static Integer[] convertToInt(String strNums) {
+        String[] strArr = strNums.split(" ");
+        Integer[] intArr = new Integer[strArr.length];
+        for (int i = 0; i < strArr.length; i++) {
+            intArr[i] = Integer.parseInt(strArr[i]);
+        }
+        return intArr;
+    }
+
+    // 取最值方法
+    private static void MaxAndMin(List<Integer> numbers) {
+        // 创建一个迭代器
+        Iterator<Integer> iterator = numbers.iterator();
+        int num;
+        // 假设最大和最小值同为第一个元素
+        int max = numbers.get(0);
+        int min = numbers.get(0);
+        while (iterator.hasNext()) {
+            num = iterator.next();
+            max = Math.max(max, num);
+            min = Math.min(min, num);
+        }
+        System.out.println("最大值为：" + max + "\n" + "最小值为：" + min);
+    }
+
+    // 获取平均值
+    private static double getAverage(List<Integer> numbers) {
+        double sum = 0;
+        for (int num : numbers) {
+            sum += num;
+        }
+        return sum / numbers.size();
+    }
+
+    public static void main(String[] args) {
+        Scanner nums;
+        String strNums;
+        Integer[] intArr;
+        Integer[] selectNumbers = {1, 2, 3, 4, 5, 6};//控件数组
+        System.out.println("欢迎使用多功能数字处理程序！");
+
+        Scanner select = new Scanner(System.in);
+        int selectNum = 1;
+        while (selectNum != 6) {
+            System.out.println("请选择操作：");
+            System.out.println("1. 取绝对值" + " " + "2. 取最值" + " " + "3. 四舍五入" + " " + "4. 生产随机数" + " " + "5. 计算平均值" + " " + "6.退出");
+            selectNum = select.nextInt();
+            if (!Arrays.asList(selectNumbers).contains(selectNum)) {
+                try {
+                    throw new NoSuchElementException();
+                } catch (NoSuchElementException e) {
+                    System.out.println("输入无效，请重新输入。");
+                    selectNum = select.nextInt();
+                }
+            }
+            switch (selectNum) {
+                case (1):
+                    System.out.println("请输入一个数字：");
+                    Scanner num = new Scanner(System.in);
+                    System.out.println("该数字的绝对值为：" + abs(num.nextDouble()));
+                    continue;
+                case (2):
+                    System.out.println("请输入一组数字，以空格分隔：");
+                    nums = new Scanner(System.in);
+                    strNums = nums.nextLine();
+                    intArr = convertToInt(strNums);
+                    List<Integer> numbers1 = Arrays.asList(intArr);
+                    MaxAndMin(numbers1);
+                    continue;
+                case (3):
+                    System.out.println("请输入一个数字：");
+                    Scanner num1 = new Scanner(System.in);
+                    System.out.println("该数字的四舍五入值为：" + Math.round(num1.nextDouble()));
+                    continue;
+                case (4):
+                    System.out.println("请输入一个范围（例如：1-10）：");
+                    Scanner range = new Scanner(System.in);
+                    int min = range.nextInt();
+                    int max = range.nextInt();
+                    System.out.println("生成的随机数为：" + (int) (Math.random() * (max - min + 1)) + min);
+                    continue;
+                case (5):
+                    System.out.println("请输入一组数字，以空格分隔：");
+                    nums = new Scanner(System.in);
+                    strNums = nums.nextLine();
+                    intArr = convertToInt(strNums);
+                    List<Integer> numbers2 = Arrays.asList(intArr);
+                    System.out.println("该组数字的平均值为：" + getAverage(numbers2));
+                    continue;
+                case (6):
+                    System.out.println("程序已退出。");
+                    break;
+            }
+        }
+    }
+}
diff --git "a/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/ObjectDemo.java" "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/ObjectDemo.java"
new file mode 100644
index 0000000000000000000000000000000000000000..f7fbf0f8149241d7c4dff6100ff257bd00d6a8b8
--- /dev/null
+++ "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/ObjectDemo.java"
@@ -0,0 +1,62 @@
+package com.java.minxi.java_20240516.java_2302_刘宗旭_2344310210;
+
+class Person {
+    private String name;
+    private Integer age;
+
+    // 有参构造器
+    public Person(String name,int age) {
+        this.name = name;
+        this.age = age;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public int getAge() {
+        return age;
+    }
+
+    public void setAge(int age) {
+        this.age = age;
+    }
+
+    // 重写toString方法
+    @Override
+    public String toString() {
+        return this.name + " is " + this.age + " years old.";
+    }
+
+    // 重写equals方法
+    @Override
+    public boolean equals(Object obj) {
+        String strAge = String.valueOf(this.age);
+        if (obj instanceof Person) {
+            Person other = (Person) obj;//如果obj是Person类的实例，将其转换为Person类型
+            return this.name.equals(other.name) && strAge.equals(String.valueOf(other.age));
+        }
+        return false;
+    }
+}
+
+public class ObjectDemo {
+    public static void main(String[] args) {
+        Person p = new Person("牧濑红莉栖",18);
+        Person p2 = new Person("稚名真由理",16);
+        Person p3 = new Person("牧濑红莉栖",19);
+        Person p4 = new Person("稚名真由理",18);
+
+        // 测试重写后的toString方法
+        System.out.println(p);
+
+        // 测试重写后的equals方法
+        System.out.println(p.equals(p2));
+        System.out.println(p.equals(p3));
+        System.out.println(p.equals(p4));
+    }
+}
diff --git "a/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/StringDemo.java" "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/StringDemo.java"
new file mode 100644
index 0000000000000000000000000000000000000000..de174b84db007a870b9e2d6bc3aeae65b5fb11e5
--- /dev/null
+++ "b/work/com/java/minxi/java_20240516/java_2302_\345\210\230\345\256\227\346\227\255_2344310210/StringDemo.java"
@@ -0,0 +1,156 @@
+package com.java.minxi.java_20240516.java_2302_刘宗旭_2344310210;
+
+import java.util.Arrays;
+
+public class StringDemo {
+    // 字符串连接
+    public String concatString(String str1, String str2) {
+        return str1 + str2;
+    }
+
+    //获取字符串长度
+    public int getStrLength(String str) {
+        return str.length();
+    }
+
+    // 字符串反转
+    public String reverseString(String str) {
+        StringBuilder sb = new StringBuilder(str);
+        return sb.reverse().toString();
+    }
+
+    // 字符串大小写切换
+    public String switchCase(String str) {
+        return str.toUpperCase();
+    }
+
+    // 字符串搜索(一个字符串是否包含另一个字符串)
+    public boolean searchString(String str1, String str2) {
+        return str1.contains(str2);
+    }
+
+    // 字符串替换
+    public String replaceString(String str, String oldStr, String newStr) {
+        return str.replace(oldStr, newStr);
+    }
+
+    // 字符串分割
+    public String[] splitString(String str, String delimiter) {
+        return str.split(delimiter);
+    }
+
+    // 字符串修剪
+    public String trimString(String str) {
+        return str.trim();
+    }
+
+    // 字符串比较（忽略大小写）
+    public int compareStringIgnoreCase(String str1, String str2) {
+        return str1.compareToIgnoreCase(str2);
+    }
+
+    // 提取字符串中指定范围的字符
+    public String extractSubstring(String str, int startIndex, int endIndex) {
+        return str.substring(startIndex, endIndex);
+    }
+
+    // 检查字符串的特定后缀
+    public boolean checkSuffix(String str, String suffix) {
+        return str.endsWith(suffix);
+    }
+
+    // 检查字符串的特定前缀
+    public boolean checkPrefix(String str, String prefix) {
+        return str.startsWith(prefix);
+    }
+
+    //检查字符串中字符出现次数
+    public int countChar(String str, char ch) {
+        return str.length() - str.replace(String.valueOf(ch), "").length();
+    }
+
+    // 类型转换（字符串与数字）
+    public String convert(int number){
+        return String.valueOf(number);
+    }
+
+    // 重载：类型转换（数字与字符串）
+    public Integer convert(String str){
+        return Integer.valueOf(str);
+    }
+
+    public static void main(String[] args) {
+        StringDemo stringDemo = new StringDemo();
+
+        // 示例：字符串连接
+        String str1 = "Hello ";
+        String str2 = " World";
+        String result = stringDemo.concatString(str1, str2);
+        System.out.println("连接后的字符串: " + result);
+
+        // 示例：获取字符串长度
+        int length = stringDemo.getStrLength(str1);
+        System.out.println("字符串长度: " + length);
+
+        // 示例：字符串反转
+        String reversed = stringDemo.reverseString(str1);
+        System.out.println("反转后的字符串: " + reversed);
+
+        // 示例：字符串大小写切换
+        String switched = stringDemo.switchCase(str1);
+        System.out.println("大小写切换后的字符串: " + switched);
+
+        // 示例：字符串查找
+        String str3 = "llo";
+        boolean found = stringDemo.searchString(str1, str3);
+        System.out.println("字符串查找结果: " + found);
+
+        // 示例：字符串替换
+        String replaced = stringDemo.replaceString(str1, "l", "L");
+        System.out.println("替换后的字符串: " + replaced);
+
+        // 示例：字符串分割
+        String[] parts = stringDemo.splitString(str1, "");
+        System.out.println("分割后的字符串数组: " + Arrays.toString(parts));
+
+        // 实例：字符串修剪
+        System.out.println("原始字符串: " + str2);
+        String trimmed = stringDemo.trimString(str2);
+        System.out.println("修剪后的字符串: " + trimmed);
+
+        // 示例：字符串比较
+        int comparison = stringDemo.compareStringIgnoreCase(str1, str2);
+        System.out.println("字符串比较结果: " + comparison);
+
+        // 示例：字符串截取
+        String subStr = stringDemo.extractSubstring(str1, 2, 4);
+        System.out.println("截取后的字符串: " + subStr);
+
+        // 示例：检查字符串后缀
+        boolean hasSuffix = stringDemo.checkSuffix(str1, "lo");
+        System.out.println("字符串是否以'lo'结尾: " + hasSuffix);
+
+        // 示例：检查字符串前缀
+        boolean hasPrefix = stringDemo.checkPrefix(str1, "He");
+        System.out.println("字符串是否以'He'开头: " + hasPrefix);
+
+        // 示例：统计字符出现次数
+        int count = stringDemo.countChar(str1, 'l');
+        System.out.println("字符'l'在字符串中出现的次数: " + count);
+
+        // 示例：将字符串转换为整数
+        int num = stringDemo.convert("123");
+        System.out.println("转换后的整数: " + num);
+
+        // 示例：将整数转换为字符串
+        String numStr = stringDemo.convert(123);
+        System.out.println("转换后的字符串: " + numStr);
+
+        //StringBuilder拼接
+        StringBuilder sb = new StringBuilder();
+        sb.append("Hello");
+        sb.append(" ");
+        sb.append("World");
+        System.out.println("拼接后的字符串: " + sb);
+    }
+}