diff --git a/src/Notes-master/app/src/main/java/net/micode/notes/tool/DataUtils.java b/src/Notes-master/app/src/main/java/net/micode/notes/tool/DataUtils.java
index 2a14982..61f56d2 100644
--- a/src/Notes-master/app/src/main/java/net/micode/notes/tool/DataUtils.java
+++ b/src/Notes-master/app/src/main/java/net/micode/notes/tool/DataUtils.java
@@ -34,9 +34,22 @@ import net.micode.notes.ui.NotesListAdapter.AppWidgetAttribute;
 import java.util.ArrayList;
 import java.util.HashSet;
 
-
+/**
+ * 数据操作工具类
+ * 提供对笔记数据的各种操作方法，包括批量删除、移动笔记、查询数据等功能
+ * 所有方法均为静态方法，可直接调用
+ */
 public class DataUtils {
     public static final String TAG = "DataUtils";
+
+    /**
+     * 批量删除笔记
+     * 使用ContentProvider的批量操作功能高效删除多个笔记
+     * 
+     * @param resolver 内容解析器
+     * @param ids 要删除的笔记ID集合
+     * @return 删除操作是否成功
+     */
     public static boolean batchDeleteNotes(ContentResolver resolver, HashSet<Long> ids) {
         if (ids == null) {
             Log.d(TAG, "the ids is null");
@@ -49,15 +62,18 @@ public class DataUtils {
 
         ArrayList<ContentProviderOperation> operationList = new ArrayList<ContentProviderOperation>();
         for (long id : ids) {
+            // 避免删除系统根文件夹
             if(id == Notes.ID_ROOT_FOLDER) {
                 Log.e(TAG, "Don't delete system folder root");
                 continue;
             }
+            // 构建删除操作
             ContentProviderOperation.Builder builder = ContentProviderOperation
                     .newDelete(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id));
             operationList.add(builder.build());
         }
         try {
+            // 执行批量操作
             ContentProviderResult[] results = resolver.applyBatch(Notes.AUTHORITY, operationList);
             if (results == null || results.length == 0 || results[0] == null) {
                 Log.d(TAG, "delete notes failed, ids:" + ids.toString());
@@ -72,14 +88,33 @@ public class DataUtils {
         return false;
     }
 
+    /**
+     * 将单个笔记移动到指定文件夹
+     * 
+     * @param resolver 内容解析器
+     * @param id 要移动的笔记ID
+     * @param srcFolderId 原文件夹ID
+     * @param desFolderId 目标文件夹ID
+     */
     public static void moveNoteToFoler(ContentResolver resolver, long id, long srcFolderId, long desFolderId) {
         ContentValues values = new ContentValues();
+        // 更新父文件夹ID和原始父文件夹ID
         values.put(NoteColumns.PARENT_ID, desFolderId);
         values.put(NoteColumns.ORIGIN_PARENT_ID, srcFolderId);
+        // 标记为本地修改，以便同步
         values.put(NoteColumns.LOCAL_MODIFIED, 1);
         resolver.update(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id), values, null, null);
     }
 
+    /**
+     * 批量将笔记移动到指定文件夹
+     * 使用ContentProvider的批量操作功能高效移动多个笔记
+     * 
+     * @param resolver 内容解析器
+     * @param ids 要移动的笔记ID集合
+     * @param folderId 目标文件夹ID
+     * @return 移动操作是否成功
+     */
     public static boolean batchMoveToFolder(ContentResolver resolver, HashSet<Long> ids,
             long folderId) {
         if (ids == null) {
@@ -89,6 +124,7 @@ public class DataUtils {
 
         ArrayList<ContentProviderOperation> operationList = new ArrayList<ContentProviderOperation>();
         for (long id : ids) {
+            // 构建更新操作
             ContentProviderOperation.Builder builder = ContentProviderOperation
                     .newUpdate(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, id));
             builder.withValue(NoteColumns.PARENT_ID, folderId);
@@ -97,9 +133,10 @@ public class DataUtils {
         }
 
         try {
+            // 执行批量操作
             ContentProviderResult[] results = resolver.applyBatch(Notes.AUTHORITY, operationList);
             if (results == null || results.length == 0 || results[0] == null) {
-                Log.d(TAG, "delete notes failed, ids:" + ids.toString());
+                Log.d(TAG, "move notes failed, ids:" + ids.toString());
                 return false;
             }
             return true;
@@ -112,18 +149,22 @@ public class DataUtils {
     }
 
     /**
-     * Get the all folder count except system folders {@link Notes#TYPE_SYSTEM}}
+     * 获取用户创建的文件夹数量（不包括系统文件夹）
+     * 
+     * @param resolver 内容解析器
+     * @return 用户文件夹数量
      */
     public static int getUserFolderCount(ContentResolver resolver) {
-        Cursor cursor =resolver.query(Notes.CONTENT_NOTE_URI,
+        // 查询类型为文件夹且不是垃圾桶的记录数量
+        Cursor cursor = resolver.query(Notes.CONTENT_NOTE_URI,
                 new String[] { "COUNT(*)" },
                 NoteColumns.TYPE + "=? AND " + NoteColumns.PARENT_ID + "<>?",
-                new String[] { String.valueOf(Notes.TYPE_FOLDER), String.valueOf(Notes.ID_TRASH_FOLER)},
+                new String[] { String.valueOf(Notes.TYPE_FOLDER), String.valueOf(Notes.ID_TRASH_FOLER) },
                 null);
 
         int count = 0;
-        if(cursor != null) {
-            if(cursor.moveToFirst()) {
+        if (cursor != null) {
+            if (cursor.moveToFirst()) {
                 try {
                     count = cursor.getInt(0);
                 } catch (IndexOutOfBoundsException e) {
@@ -136,11 +177,19 @@ public class DataUtils {
         return count;
     }
 
+    /**
+     * 检查笔记在数据库中是否可见（非垃圾桶中的指定类型笔记）
+     * 
+     * @param resolver 内容解析器
+     * @param noteId 笔记ID
+     * @param type 笔记类型
+     * @return 是否可见
+     */
     public static boolean visibleInNoteDatabase(ContentResolver resolver, long noteId, int type) {
         Cursor cursor = resolver.query(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId),
                 null,
                 NoteColumns.TYPE + "=? AND " + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER,
-                new String [] {String.valueOf(type)},
+                new String[] { String.valueOf(type) },
                 null);
 
         boolean exist = false;
@@ -153,6 +202,13 @@ public class DataUtils {
         return exist;
     }
 
+    /**
+     * 检查笔记是否存在于数据库中
+     * 
+     * @param resolver 内容解析器
+     * @param noteId 笔记ID
+     * @return 是否存在
+     */
     public static boolean existInNoteDatabase(ContentResolver resolver, long noteId) {
         Cursor cursor = resolver.query(ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId),
                 null, null, null, null);
@@ -167,6 +223,13 @@ public class DataUtils {
         return exist;
     }
 
+    /**
+     * 检查数据项是否存在于数据库中
+     * 
+     * @param resolver 内容解析器
+     * @param dataId 数据项ID
+     * @return 是否存在
+     */
     public static boolean existInDataDatabase(ContentResolver resolver, long dataId) {
         Cursor cursor = resolver.query(ContentUris.withAppendedId(Notes.CONTENT_DATA_URI, dataId),
                 null, null, null, null);
@@ -181,6 +244,13 @@ public class DataUtils {
         return exist;
     }
 
+    /**
+     * 检查文件夹名称是否已存在（非垃圾桶中的文件夹）
+     * 
+     * @param resolver 内容解析器
+     * @param name 文件夹名称
+     * @return 是否存在同名文件夹
+     */
     public static boolean checkVisibleFolderName(ContentResolver resolver, String name) {
         Cursor cursor = resolver.query(Notes.CONTENT_NOTE_URI, null,
                 NoteColumns.TYPE + "=" + Notes.TYPE_FOLDER +
@@ -188,8 +258,8 @@ public class DataUtils {
                 " AND " + NoteColumns.SNIPPET + "=?",
                 new String[] { name }, null);
         boolean exist = false;
-        if(cursor != null) {
-            if(cursor.getCount() > 0) {
+        if (cursor != null) {
+            if (cursor.getCount() > 0) {
                 exist = true;
             }
             cursor.close();
@@ -197,6 +267,13 @@ public class DataUtils {
         return exist;
     }
 
+    /**
+     * 获取文件夹关联的小部件属性
+     * 
+     * @param resolver 内容解析器
+     * @param folderId 文件夹ID
+     * @return 小部件属性集合
+     */
     public static HashSet<AppWidgetAttribute> getFolderNoteWidget(ContentResolver resolver, long folderId) {
         Cursor c = resolver.query(Notes.CONTENT_NOTE_URI,
                 new String[] { NoteColumns.WIDGET_ID, NoteColumns.WIDGET_TYPE },
@@ -224,11 +301,18 @@ public class DataUtils {
         return set;
     }
 
+    /**
+     * 根据笔记ID获取关联的电话号码
+     * 
+     * @param resolver 内容解析器
+     * @param noteId 笔记ID
+     * @return 电话号码，不存在则返回空字符串
+     */
     public static String getCallNumberByNoteId(ContentResolver resolver, long noteId) {
         Cursor cursor = resolver.query(Notes.CONTENT_DATA_URI,
-                new String [] { CallNote.PHONE_NUMBER },
+                new String[] { CallNote.PHONE_NUMBER },
                 CallNote.NOTE_ID + "=? AND " + CallNote.MIME_TYPE + "=?",
-                new String [] { String.valueOf(noteId), CallNote.CONTENT_ITEM_TYPE },
+                new String[] { String.valueOf(noteId), CallNote.CONTENT_ITEM_TYPE },
                 null);
 
         if (cursor != null && cursor.moveToFirst()) {
@@ -243,12 +327,20 @@ public class DataUtils {
         return "";
     }
 
+    /**
+     * 根据电话号码和通话时间获取关联的笔记ID
+     * 
+     * @param resolver 内容解析器
+     * @param phoneNumber 电话号码
+     * @param callDate 通话时间
+     * @return 笔记ID，不存在则返回0
+     */
     public static long getNoteIdByPhoneNumberAndCallDate(ContentResolver resolver, String phoneNumber, long callDate) {
         Cursor cursor = resolver.query(Notes.CONTENT_DATA_URI,
-                new String [] { CallNote.NOTE_ID },
+                new String[] { CallNote.NOTE_ID },
                 CallNote.CALL_DATE + "=? AND " + CallNote.MIME_TYPE + "=? AND PHONE_NUMBERS_EQUAL("
                 + CallNote.PHONE_NUMBER + ",?)",
-                new String [] { String.valueOf(callDate), CallNote.CONTENT_ITEM_TYPE, phoneNumber },
+                new String[] { String.valueOf(callDate), CallNote.CONTENT_ITEM_TYPE, phoneNumber },
                 null);
 
         if (cursor != null) {
@@ -264,11 +356,19 @@ public class DataUtils {
         return 0;
     }
 
+    /**
+     * 根据笔记ID获取笔记摘要
+     * 
+     * @param resolver 内容解析器
+     * @param noteId 笔记ID
+     * @return 笔记摘要
+     * @throws IllegalArgumentException 当笔记不存在时抛出
+     */
     public static String getSnippetById(ContentResolver resolver, long noteId) {
         Cursor cursor = resolver.query(Notes.CONTENT_NOTE_URI,
-                new String [] { NoteColumns.SNIPPET },
+                new String[] { NoteColumns.SNIPPET },
                 NoteColumns.ID + "=?",
-                new String [] { String.valueOf(noteId)},
+                new String[] { String.valueOf(noteId) },
                 null);
 
         if (cursor != null) {
@@ -282,6 +382,13 @@ public class DataUtils {
         throw new IllegalArgumentException("Note is not found with id: " + noteId);
     }
 
+    /**
+     * 格式化笔记摘要
+     * 去除前后空格，并截断第一个换行符之前的内容
+     * 
+     * @param snippet 原始摘要
+     * @return 格式化后的摘要
+     */
     public static String getFormattedSnippet(String snippet) {
         if (snippet != null) {
             snippet = snippet.trim();
@@ -292,4 +399,4 @@ public class DataUtils {
         }
         return snippet;
     }
-}
+}
\ No newline at end of file