diff --git a/Java/TodoListApp/src/DatabaseManager.java b/Java/TodoListApp/src/DatabaseManager.java
index 7f90ccf..2105d8b 100644
--- a/Java/TodoListApp/src/DatabaseManager.java
+++ b/Java/TodoListApp/src/DatabaseManager.java
@@ -59,4 +59,3 @@ public class DatabaseManager {
         }
     }
 }
-
diff --git a/Java/TodoListApp/src/TodoListManager.java b/Java/TodoListApp/src/TodoListManager.java
index 80bc1dc..dedf5b4 100644
--- a/Java/TodoListApp/src/TodoListManager.java
+++ b/Java/TodoListApp/src/TodoListManager.java
@@ -1,118 +1,61 @@
 package TodoListApp.src;
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.util.ArrayList;
+
+import java.sql.SQLException;
 import java.util.List;
-import java.time.LocalDateTime;
-import java.time.format.DateTimeFormatter;
-// 待办事项管理类
-class TodoListManager {
-    private final List<TodoItem> todoList;
-    private int nextId;
-    // private DatabaseManager dbManager; // 暂时注释掉
+
+public class TodoListManager {
+    private DatabaseManager dbManager;
 
     public TodoListManager() {
-        todoList = new ArrayList<>();
-        nextId = 1; // 起始编号
-        // dbManager = new DatabaseManager(); // 
+        dbManager = new DatabaseManager();
     }
 
-    // 添加待办事项
-    public void addTodo(String description) throws EmptyDescriptionException{ //同时声明可能抛出的异常类型
-        if(description == null || description.trim().isEmpty()){
-            EmptyDescriptionException e = new EmptyDescriptionException("待办事项的描述不能为空。");
-            throw e;
+    public void addTodo(String description) throws EmptyDescriptionException {
+        if (description == null || description.trim().isEmpty()) {
+            throw new EmptyDescriptionException("待办事项描述不能为空。");
+        }
+        try {
+            dbManager.addTodo(description);
+            System.out.println("待办事项已添加。");
+        } catch (SQLException e) {
+            System.out.println("添加待办事项时发生错误：" + e.getMessage());
         }
-        TodoItem item = new TodoItem(nextId++, description);
-        todoList.add(item);
-        System.out.println("待办事项已添加： " + item);
     }
 
-    // 列出所有待办事项
     public void listTodos() {
-        if (todoList.isEmpty()) {
-            System.out.println("当前没有待办事项。");
-            return;
-        }
-        System.out.println("\n===== 待办事项列表 =====");
-        for (TodoItem item : todoList) {
-            System.out.println(item);
+        try {
+            List<TodoItem> todos = dbManager.getAllTodos();
+            if (todos.isEmpty()) {
+                System.out.println("没有待办事项。");
+            } else {
+                for (TodoItem todo : todos) {
+                    System.out.println(todo);
+                }
+            }
+        } catch (SQLException e) {
+            System.out.println("获取待办事项列表时发生错误：" + e.getMessage());
         }
     }
 
-    // 删除指定编号的待办事项
-    public void removeTodo(int id) throws TodoNotFoundException{
-        boolean removed = false;
-        for (TodoItem item : todoList) {
-            if (item.getId() == id) {
-                todoList.remove(item);
-                System.out.println("已删除待办事项： " + item);
-                removed = true;
-                break;
-            }
-        }
-        if (!removed) {
-            throw new TodoNotFoundException("未找到编号为 " + id + " 的待办事项。");
-            //System.out.println("未找到编号为 " + id + " 的待办事项。");
+    public void removeTodo(int id) throws TodoNotFoundException {
+        try {
+            dbManager.removeTodo(id);
+            System.out.println("待办事项已删除。");
+        } catch (SQLException e) {
+            throw new TodoNotFoundException("未找到ID为 " + id + " 的待办事项。");
         }
     }
 
     public void markAsCompleted(int id) {
-        TodoItem item = null;
-        for (TodoItem todo : todoList) {
-            if (todo.getId() == id) {
-                item = todo;
-                break;
-            }
-
-        }
-        if (item != null) {
-            if (!item.isCompleted()) {
-                item.setCompleted(true);
-                System.out.println("待办事项已标记为完成： " + item);
-            } else {
-                System.out.println("待办事项已完成，无需重复标记。");
-            }
-        }
-        else {
-            System.out.println("未找到编号为：" + id + " 的待办事项。");
-        }
-    }
-
-    public void saveToFile(String filename){
-
         try {
-            File file = new File(filename);
-            FileOutputStream fos = new FileOutputStream(file);
-
-            for (TodoItem item : todoList) {
-                String line = item.getId() + ":" + item.getDescription() + "\n";
-                fos.write(line.getBytes());
-            }
-            System.out.println("待办事项已经保存到文件：" + filename);
-
-            fos.close();
-        }
-        catch (IOException e){
-            System.out.println("待办事项保存失败：" + e.getMessage());
+            dbManager.markAsCompleted(id);
+            System.out.println("待办事项已标记为完成。");
+        } catch (SQLException e) {
+            System.out.println("标记待办事项时发生错误：" + e.getMessage());
         }
     }
 
-    private void backupToFile(String backupFilename) {
-        LocalDateTime now = LocalDateTime.now();
-        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd_HH-mm-ss");
-        String timestamp = now.format(formatter);
-        String fullBackupFilename = backupFilename + "_" + timestamp + ".bak";
-
-        try (FileOutputStream fos = new FileOutputStream(new File(fullBackupFilename))) {
-            for (TodoItem item : todoList) {
-                String line = item.getId() + ":" + item.getDescription() + ":" + (item.isCompleted() ? "完成" : "未完成") + "\n";
-                fos.write(line.getBytes());
-            }
-            System.out.println("待办事项已备份到文件：" + fullBackupFilename);
-        } catch (IOException e) {
-            System.out.println("待办事项备份失败：" + e.getMessage());
-        }
+    public void saveToFile(String filename) {
+        System.out.println("数据已保存在数据库中，无需额外保存到文件。");
     }
 }