完成数据库更新

Java/TodoListApp/src/DatabaseManager.java

@@ -0,0 +1,62 @@
+package TodoListApp.src;
+
+import java.sql.*;
+import java.util.ArrayList;
+import java.util.List;
+
+public class DatabaseManager {
+    private static final String URL = "jdbc:mysql://localhost:3306/TodoList";
+    private static final String USER = "root";
+    private static final String PASSWORD = "123456";
+
+    public DatabaseManager() {
+        try {
+            Class.forName("com.mysql.cj.jdbc.Driver");
+        } catch (ClassNotFoundException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public void addTodo(String description) throws SQLException {
+        String sql = "INSERT INTO todos (description) VALUES (?)";
+        try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD);
+             PreparedStatement pstmt = conn.prepareStatement(sql)) {
+            pstmt.setString(1, description);
+            pstmt.executeUpdate();
+        }
+    }
+
+    public List<TodoItem> getAllTodos() throws SQLException {
+        List<TodoItem> todos = new ArrayList<>();
+        String sql = "SELECT * FROM todos";
+        try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD);
+             Statement stmt = conn.createStatement();
+             ResultSet rs = stmt.executeQuery(sql)) {
+            while (rs.next()) {
+                int id = rs.getInt("id");
+                String description = rs.getString("description");
+                todos.add(new TodoItem(id, description));
+            }
+        }
+        return todos;
+    }
+
+    public void removeTodo(int id) throws SQLException {
+        String sql = "DELETE FROM todos WHERE id = ?";
+        try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD);
+             PreparedStatement pstmt = conn.prepareStatement(sql)) {
+            pstmt.setInt(1, id);
+            pstmt.executeUpdate();
+        }
+    }
+
+    public void markAsCompleted(int id) throws SQLException {
+        String sql = "UPDATE todos SET completed = true WHERE id = ?";
+        try (Connection conn = DriverManager.getConnection(URL, USER, PASSWORD);
+             PreparedStatement pstmt = conn.prepareStatement(sql)) {
+            pstmt.setInt(1, id);
+            pstmt.executeUpdate();
+        }
+    }
+}
+