diff --git a/Contact.java b/Contact.java
new file mode 100644
index 0000000..4aa2567
--- /dev/null
+++ b/Contact.java
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.data;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.provider.ContactsContract.CommonDataKinds.Phone;
+import android.provider.ContactsContract.Data;
+import android.telephony.PhoneNumberUtils;
+import android.util.Log;
+
+import java.util.HashMap;
+
+public class Contact {
+    private static HashMap<String, String> sContactCache; // 静态HashMap用于缓存联系人信息
+    private static final String TAG = "Contact"; // 用于日志记录的标签
+
+    // 这是一个SQL查询片段，用于在联系人数据库中查找与给定电话号码匹配的联系人
+    // 此查询片段使用了PHONE_NUMBERS_EQUAL函数来匹配电话号码，并检查MIME类型是否为联系人类型
+    // 然后，它使用子查询从phone_lookup表中选择具有最佳匹配的raw_contact_id
+    // 请注意，这里的"?"是一个参数占位符，用于在执行查询时插入实际的电话号码
+    private static final String CALLER_ID_SELECTION = "PHONE_NUMBERS_EQUAL(" + Phone.NUMBER
+    + ",?) AND " + Data.MIMETYPE + "='" + Phone.CONTENT_ITEM_TYPE + "'"
+    + " AND " + Data.RAW_CONTACT_ID + " IN "
+            + "(SELECT raw_contact_id "
+            + " FROM phone_lookup"
+            + " WHERE min_match = '+')";
+
+    /**
+     * 根据电话号码从联系人数据库中获取联系人的姓名，并缓存结果。
+     *
+     * @param context 当前应用的上下文，用于访问内容解析器。
+     * @param phoneNumber 要查询的电话号码。
+     * @return 匹配电话号码的联系人姓名，如果未找到匹配项或发生错误，则返回null。
+     */
+
+    public static String getContact(Context context, String phoneNumber) {
+        // 检查缓存是否已初始化，如果未初始化，则进行初始化
+        if(sContactCache == null) {
+            sContactCache = new HashMap<String, String>();
+        }
+        // 检查缓存中是否已经存在该电话号码的联系人姓名
+        if(sContactCache.containsKey(phoneNumber)) {
+            return sContactCache.get(phoneNumber);
+        }
+        // 替换CALLER_ID_SELECTION中的占位符"+"为实际的电话号码匹配最小值
+        String selection = CALLER_ID_SELECTION.replace("+",
+                PhoneNumberUtils.toCallerIDMinMatch(phoneNumber));
+        // 使用内容解析器查询联系人数据库
+        Cursor cursor = context.getContentResolver().query(
+                Data.CONTENT_URI,
+                new String [] { Phone.DISPLAY_NAME },
+                selection,
+                new String[] { phoneNumber },
+                null);
+        // 处理查询结果
+        if (cursor != null && cursor.moveToFirst()) {
+            try {
+                String name = cursor.getString(0);
+                sContactCache.put(phoneNumber, name);
+                return name;
+            } catch (IndexOutOfBoundsException e) {
+                // 如果Cursor中没有预期的列，则记录错误并返回null
+                Log.e(TAG, " Cursor get string error " + e.toString());
+                return null;
+            } finally {
+                cursor.close();
+            }
+        } else {
+            Log.d(TAG, "No contact matched with number:" + phoneNumber);
+            return null;
+        }
+    }
+}
diff --git a/Notes.java b/Notes.java
new file mode 100644
index 0000000..9cd93a6
--- /dev/null
+++ b/Notes.java
@@ -0,0 +1,299 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.data;
+import android.net.Uri; // 导入Android的Uri类，用于表示资源的统一资源标识符（URI）
+public class Notes {
+    // 定义一个常量，作为内容提供者（Content Provider）的权限（Authority），用于唯一标识内容提供者
+    public static final String AUTHORITY = "micode_notes";
+    // 定义一个常量，用作日志标签（Tag），在打印日志信息时用于区分日志来源
+    public static final String TAG = "Notes";
+    // 定义三种笔记类型的常量
+    // TYPE_NOTE 代表普通笔记类型
+    public static final int TYPE_NOTE = 0;
+    // TYPE_FOLDER 代表文件夹类型，可能用于组织笔记
+    public static final int TYPE_FOLDER = 1;
+    // TYPE_SYSTEM 代表系统级笔记或特殊类型的笔记，可能包含应用内部使用的笔记或特殊功能
+    public static final int TYPE_SYSTEM = 2;
+    /**
+     * Following IDs are system folders' identifiers
+     * {@link Notes#ID_ROOT_FOLDER } is default folder
+     * {@link Notes#ID_TEMPARAY_FOLDER } is for notes belonging no folder
+     * {@link Notes#ID_CALL_RECORD_FOLDER} is to store call records
+     */
+    // 文件夹ID常量
+// 根文件夹的ID，通常用于表示最高级别的文件夹或笔记的顶级组织
+    public static final int ID_ROOT_FOLDER = 0;
+    // 临时文件夹的ID，可能用于存放临时笔记或数据
+    public static final int ID_TEMPARAY_FOLDER = -1; // 注意：这里可能是拼写错误，应为 TEMPORARY
+    // 通话记录文件夹的ID，用于存放与通话相关的笔记或记录
+    public static final int ID_CALL_RECORD_FOLDER = -2;
+    // 回收站文件夹的ID，用于存放被删除的笔记，以便用户可以恢复它们
+    public static final int ID_TRASH_FOLER = -3; // 注意：这里可能是拼写错误，应为 TRASH_FOLDER
+    // Intent额外数据键常量
+// 用于Intent中传递提醒日期的键
+    public static final String INTENT_EXTRA_ALERT_DATE = "net.micode.notes.alert_date";
+    // 用于Intent中传递背景颜色ID的键
+    public static final String INTENT_EXTRA_BACKGROUND_ID = "net.micode.notes.background_color_id";
+    // 用于Intent中传递小部件ID的键
+    public static final String INTENT_EXTRA_WIDGET_ID = "net.micode.notes.widget_id";
+    // 用于Intent中传递小部件类型的键
+    public static final String INTENT_EXTRA_WIDGET_TYPE = "net.micode.notes.widget_type";
+    // 用于Intent中传递文件夹ID的键
+    public static final String INTENT_EXTRA_FOLDER_ID = "net.micode.notes.folder_id";
+    // 用于Intent中传递通话记录日期的键
+    public static final String INTENT_EXTRA_CALL_DATE = "net.micode.notes.call_date";
+    // 小部件类型常量
+// 无效的小部件类型
+    public static final int TYPE_WIDGET_INVALIDE = -1; // 注意：这里可能是拼写错误，应为 INVALID
+    // 2x大小的小部件类型
+    public static final int TYPE_WIDGET_2X = 0;
+    // 4x大小的小部件类型
+    public static final int TYPE_WIDGET_4X = 1;
+    // 数据类型常量类
+    public static class DataConstants {
+        // 文本笔记的内容类型常量，这里假设TextNote.CONTENT_ITEM_TYPE是一个在TextNote类中定义的常量
+        public static final String NOTE = TextNote.CONTENT_ITEM_TYPE;
+        // 通话笔记的内容类型常量，这里假设CallNote.CONTENT_ITEM_TYPE是一个在CallNote类中定义的常量
+        // public static final String CALL_NOTE = CallNote.CONTENT_ITEM_TYPE;
+        // DataConstants类可能包含更多与数据类型相关的常量
+    }
+    /**
+     * Uri to query all notes and folders
+     */
+    public static final Uri CONTENT_NOTE_URI = Uri.parse("content://" + AUTHORITY + "/note");
+
+    /**
+     * Uri to query data
+     */
+    public static final Uri CONTENT_DATA_URI = Uri.parse("content://" + AUTHORITY + "/data");
+
+    public interface NoteColumns {
+        /**
+         * The unique ID for a row
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String ID = "_id";
+
+        /**
+         * The parent's id for note or folder
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String PARENT_ID = "parent_id";
+
+        /**
+         * Created data for note or folder
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String CREATED_DATE = "created_date";
+
+        /**
+         * Latest modified date
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String MODIFIED_DATE = "modified_date";
+
+
+        /**
+         * Alert date
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String ALERTED_DATE = "alert_date";
+
+        /**
+         * Folder's name or text content of note
+         * <P> Type: TEXT </P>
+         */
+        public static final String SNIPPET = "snippet";
+
+        /**
+         * Note's widget id
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String WIDGET_ID = "widget_id";
+
+        /**
+         * Note's widget type
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String WIDGET_TYPE = "widget_type";
+
+        /**
+         * Note's background color's id
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String BG_COLOR_ID = "bg_color_id";
+
+        /**
+         * For text note, it doesn't has attachment, for multi-media
+         * note, it has at least one attachment
+         * <P> Type: INTEGER </P>
+         */
+        public static final String HAS_ATTACHMENT = "has_attachment";
+
+        /**
+         * Folder's count of notes
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String NOTES_COUNT = "notes_count";
+
+        /**
+         * The file type: folder or note
+         * <P> Type: INTEGER </P>
+         */
+        public static final String TYPE = "type";
+
+        /**
+         * The last sync id
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String SYNC_ID = "sync_id";
+
+        /**
+         * Sign to indicate local modified or not
+         * <P> Type: INTEGER </P>
+         */
+        public static final String LOCAL_MODIFIED = "local_modified";
+
+        /**
+         * Original parent id before moving into temporary folder
+         * <P> Type : INTEGER </P>
+         */
+        public static final String ORIGIN_PARENT_ID = "origin_parent_id";
+
+        /**
+         * The gtask id
+         * <P> Type : TEXT </P>
+         */
+        public static final String GTASK_ID = "gtask_id";
+
+        /**
+         * The version code
+         * <P> Type : INTEGER (long) </P>
+         */
+        public static final String VERSION = "version";
+    }
+
+    public interface DataColumns {
+        /**
+         * The unique ID for a row
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String ID = "_id";
+
+        /**
+         * The MIME type of the item represented by this row.
+         * <P> Type: Text </P>
+         */
+        public static final String MIME_TYPE = "mime_type";
+
+        /**
+         * The reference id to note that this data belongs to
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String NOTE_ID = "note_id";
+
+        /**
+         * Created data for note or folder
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String CREATED_DATE = "created_date";
+
+        /**
+         * Latest modified date
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String MODIFIED_DATE = "modified_date";
+
+        /**
+         * Data's content
+         * <P> Type: TEXT </P>
+         */
+        public static final String CONTENT = "content";
+
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * integer data type
+         * <P> Type: INTEGER </P>
+         */
+        public static final String DATA1 = "data1";
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * integer data type
+         * <P> Type: INTEGER </P>
+         */
+        public static final String DATA2 = "data2";
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * TEXT data type
+         * <P> Type: TEXT </P>
+         */
+        public static final String DATA3 = "data3";
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * TEXT data type
+         * <P> Type: TEXT </P>
+         */
+        public static final String DATA4 = "data4";
+
+        /**
+         * Generic data column, the meaning is {@link #MIMETYPE} specific, used for
+         * TEXT data type
+         * <P> Type: TEXT </P>
+         */
+        public static final String DATA5 = "data5";
+    }
+
+    public static final class TextNote implements DataColumns {
+        /**
+         * Mode to indicate the text in check list mode or not
+         * <P> Type: Integer 1:check list mode 0: normal mode </P>
+         */
+        public static final String MODE = DATA1;
+
+        public static final int MODE_CHECK_LIST = 1;
+
+        public static final String CONTENT_TYPE = "vnd.android.cursor.dir/text_note";
+
+        public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/text_note";
+
+        public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/text_note");
+    }
+
+    public static final class CallNote implements DataColumns {
+        /**
+         * Call date for this record
+         * <P> Type: INTEGER (long) </P>
+         */
+        public static final String CALL_DATE = DATA1;
+
+        /**
+         * Phone number for this record
+         * <P> Type: TEXT </P>
+         */
+        public static final String PHONE_NUMBER = DATA3;
+
+        public static final String CONTENT_TYPE = "vnd.android.cursor.dir/call_note";
+
+        public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/call_note";
+
+        public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/call_note");
+    }
+}
diff --git a/NotesDatabaseHelper.java b/NotesDatabaseHelper.java
new file mode 100644
index 0000000..19d942e
--- /dev/null
+++ b/NotesDatabaseHelper.java
@@ -0,0 +1,393 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.data;
+
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+import android.util.Log;
+
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.DataConstants;
+import net.micode.notes.data.Notes.NoteColumns;
+
+
+public class NotesDatabaseHelper extends SQLiteOpenHelper {
+    private static final String DB_NAME = "note.db";
+
+    private static final int DB_VERSION = 4;
+
+    public interface TABLE {
+        public static final String NOTE = "note";
+
+        public static final String DATA = "data";
+    }
+
+    private static final String TAG = "NotesDatabaseHelper";
+
+    private static NotesDatabaseHelper mInstance;
+
+    private static final String CREATE_NOTE_TABLE_SQL =
+            // 开始创建名为note的表
+            "CREATE TABLE " + TABLE.NOTE + "(" +
+                    // ID列，作为主键，用于唯一标识表中的每一行
+                    NoteColumns.ID + " INTEGER PRIMARY KEY," +
+                    // PARENT_ID列，用于表示当前笔记的父级ID，默认为0（可能表示没有父级或顶级笔记）
+                    NoteColumns.PARENT_ID + " INTEGER NOT NULL DEFAULT 0," +
+                    // ALERTED_DATE列，用于存储提醒日期（假设为时间戳），默认为0（可能表示没有设置提醒）
+                    NoteColumns.ALERTED_DATE + " INTEGER NOT NULL DEFAULT 0," +
+                    // BG_COLOR_ID列，用于存储笔记的背景颜色ID，默认为0（可能表示默认颜色）
+                    NoteColumns.BG_COLOR_ID + " INTEGER NOT NULL DEFAULT 0," +
+                    // CREATED_DATE列，用于存储笔记的创建日期（时间戳），默认为当前时间
+                    NoteColumns.CREATED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," +
+                    // HAS_ATTACHMENT列，用于表示笔记是否有附件，默认为0（没有附件）
+                    NoteColumns.HAS_ATTACHMENT + " INTEGER NOT NULL DEFAULT 0," +
+                    // MODIFIED_DATE列，用于存储笔记的最后修改日期（时间戳），默认为当前时间
+                    NoteColumns.MODIFIED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," +
+                    // NOTES_COUNT列，用途未明确，但可能是用于存储某种计数，默认为0
+                    NoteColumns.NOTES_COUNT + " INTEGER NOT NULL DEFAULT 0," +
+                    // SNIPPET列，用于存储笔记的摘要或简短描述，默认为空字符串
+                    NoteColumns.SNIPPET + " TEXT NOT NULL DEFAULT ''," +
+                    // TYPE列，用于存储笔记的类型，默认为0（可能表示默认类型）
+                    NoteColumns.TYPE + " INTEGER NOT NULL DEFAULT 0," +
+                    // WIDGET_ID列，用于关联笔记到特定的小部件，默认为0（可能表示不关联任何小部件）
+                    NoteColumns.WIDGET_ID + " INTEGER NOT NULL DEFAULT 0," +
+                    // WIDGET_TYPE列，用于存储小部件的类型，默认为-1（可能表示无效或未设置）
+                    NoteColumns.WIDGET_TYPE + " INTEGER NOT NULL DEFAULT -1," +
+                    // SYNC_ID列，用途未明确，但可能是用于同步目的的唯一标识符，默认为0
+                    NoteColumns.SYNC_ID + " INTEGER NOT NULL DEFAULT 0," +
+                    // LOCAL_MODIFIED列，用途未明确，但可能是用于跟踪笔记在本地的最后修改时间，默认为0
+                    NoteColumns.LOCAL_MODIFIED + " INTEGER NOT NULL DEFAULT 0," +
+                    // ORIGIN_PARENT_ID列，用途未明确，但可能是用于跟踪原始父级ID，默认为0
+                    NoteColumns.ORIGIN_PARENT_ID + " INTEGER NOT NULL DEFAULT 0," +
+                    // GTASK_ID列，用于存储与Google任务相关联的ID（如果有的话），默认为空字符串
+                    NoteColumns.GTASK_ID + " TEXT NOT NULL DEFAULT ''," +
+                    // VERSION列，用于存储笔记的版本号，默认为0
+                    NoteColumns.VERSION + " INTEGER NOT NULL DEFAULT 0" +
+                    // 结束表定义
+                    ")";
+
+    private static final String CREATE_DATA_TABLE_SQL =
+            // 开始创建名为data的表
+            "CREATE TABLE " + TABLE.DATA + "(" +
+                    // ID列，作为主键，用于唯一标识表中的每一行
+                    DataColumns.ID + " INTEGER PRIMARY KEY," +
+                    // MIME_TYPE列，用于存储数据的MIME类型，例如文本、图片等
+                    DataColumns.MIME_TYPE + " TEXT NOT NULL," +
+                    // NOTE_ID列，用于与note表中的ID关联，表示这些数据属于哪个笔记，默认为0（但实际应用中应该避免使用默认值）
+                    DataColumns.NOTE_ID + " INTEGER NOT NULL DEFAULT 0," +
+                    // 注意：这里使用了NoteColumns中的CREATED_DATE和MODIFIED_DATE，虽然它们在逻辑上可能与note表更相关，
+                    // 但如果data表确实需要记录数据的创建和修改时间，这也是可以接受的。
+                    // CREATED_DATE列，用于存储数据的创建日期（时间戳），默认为当前时间
+                    NoteColumns.CREATED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," +
+                    // MODIFIED_DATE列，用于存储数据的最后修改日期（时间戳），默认为当前时间
+                    NoteColumns.MODIFIED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," +
+                    // CONTENT列，用于存储数据的主要内容，默认为空字符串
+                    DataColumns.CONTENT + " TEXT NOT NULL DEFAULT ''," +
+                    // DATA1到DATA5列，用途未明确，但可以根据应用需求存储额外的整型或文本数据
+                    // 这些列的存在表明表的设计具有灵活性，以支持多种类型的数据存储
+                    DataColumns.DATA1 + " INTEGER," +
+                    DataColumns.DATA2 + " INTEGER," +
+                    DataColumns.DATA3 + " TEXT NOT NULL DEFAULT ''," +
+                    DataColumns.DATA4 + " TEXT NOT NULL DEFAULT ''," +
+                    DataColumns.DATA5 + " TEXT NOT NULL DEFAULT ''" +
+                    // 结束表定义
+                    ")";
+
+    private static final String CREATE_DATA_NOTE_ID_INDEX_SQL =
+        "CREATE INDEX IF NOT EXISTS note_id_index ON " +
+        TABLE.DATA + "(" + DataColumns.NOTE_ID + ");";
+
+    /**
+     * Increase folder's note count when move note to the folder
+     */
+    private static final String NOTE_INCREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER =
+        "CREATE TRIGGER increase_folder_count_on_update "+
+        " AFTER UPDATE OF " + NoteColumns.PARENT_ID + " ON " + TABLE.NOTE +
+        " BEGIN " +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + " + 1" +
+        "  WHERE " + NoteColumns.ID + "=new." + NoteColumns.PARENT_ID + ";" +
+        " END";
+
+    /**
+     * Decrease folder's note count when move note from folder
+     */
+    private static final String NOTE_DECREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER =
+        "CREATE TRIGGER decrease_folder_count_on_update " +
+        " AFTER UPDATE OF " + NoteColumns.PARENT_ID + " ON " + TABLE.NOTE +
+        " BEGIN " +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + "-1" +
+        "  WHERE " + NoteColumns.ID + "=old." + NoteColumns.PARENT_ID +
+        "  AND " + NoteColumns.NOTES_COUNT + ">0" + ";" +
+        " END";
+
+    /**
+     * Increase folder's note count when insert new note to the folder
+     */
+    private static final String NOTE_INCREASE_FOLDER_COUNT_ON_INSERT_TRIGGER =
+        "CREATE TRIGGER increase_folder_count_on_insert " +
+        " AFTER INSERT ON " + TABLE.NOTE +
+        " BEGIN " +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + " + 1" +
+        "  WHERE " + NoteColumns.ID + "=new." + NoteColumns.PARENT_ID + ";" +
+        " END";
+
+    /**
+     * Decrease folder's note count when delete note from the folder
+     */
+    private static final String NOTE_DECREASE_FOLDER_COUNT_ON_DELETE_TRIGGER =
+        "CREATE TRIGGER decrease_folder_count_on_delete " +
+        " AFTER DELETE ON " + TABLE.NOTE +
+        " BEGIN " +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.NOTES_COUNT + "=" + NoteColumns.NOTES_COUNT + "-1" +
+        "  WHERE " + NoteColumns.ID + "=old." + NoteColumns.PARENT_ID +
+        "  AND " + NoteColumns.NOTES_COUNT + ">0;" +
+        " END";
+
+    /**
+     * Update note's content when insert data with type {@link DataConstants#NOTE}
+     */
+    private static final String DATA_UPDATE_NOTE_CONTENT_ON_INSERT_TRIGGER =
+        "CREATE TRIGGER update_note_content_on_insert " +
+        " AFTER INSERT ON " + TABLE.DATA +
+        " WHEN new." + DataColumns.MIME_TYPE + "='" + DataConstants.NOTE + "'" +
+        " BEGIN" +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.SNIPPET + "=new." + DataColumns.CONTENT +
+        "  WHERE " + NoteColumns.ID + "=new." + DataColumns.NOTE_ID + ";" +
+        " END";
+
+    /**
+     * Update note's content when data with {@link DataConstants#NOTE} type has changed
+     */
+    private static final String DATA_UPDATE_NOTE_CONTENT_ON_UPDATE_TRIGGER =
+        "CREATE TRIGGER update_note_content_on_update " +
+        " AFTER UPDATE ON " + TABLE.DATA +
+        " WHEN old." + DataColumns.MIME_TYPE + "='" + DataConstants.NOTE + "'" +
+        " BEGIN" +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.SNIPPET + "=new." + DataColumns.CONTENT +
+        "  WHERE " + NoteColumns.ID + "=new." + DataColumns.NOTE_ID + ";" +
+        " END";
+
+    /**
+     * Update note's content when data with {@link DataConstants#NOTE} type has deleted
+     */
+    private static final String DATA_UPDATE_NOTE_CONTENT_ON_DELETE_TRIGGER =
+        "CREATE TRIGGER update_note_content_on_delete " +
+        " AFTER delete ON " + TABLE.DATA +
+        " WHEN old." + DataColumns.MIME_TYPE + "='" + DataConstants.NOTE + "'" +
+        " BEGIN" +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.SNIPPET + "=''" +
+        "  WHERE " + NoteColumns.ID + "=old." + DataColumns.NOTE_ID + ";" +
+        " END";
+
+    /**
+     * Delete datas belong to note which has been deleted
+     */
+    private static final String NOTE_DELETE_DATA_ON_DELETE_TRIGGER =
+        "CREATE TRIGGER delete_data_on_delete " +
+        " AFTER DELETE ON " + TABLE.NOTE +
+        " BEGIN" +
+        "  DELETE FROM " + TABLE.DATA +
+        "   WHERE " + DataColumns.NOTE_ID + "=old." + NoteColumns.ID + ";" +
+        " END";
+
+    /**
+     * Delete notes belong to folder which has been deleted
+     */
+    private static final String FOLDER_DELETE_NOTES_ON_DELETE_TRIGGER =
+        "CREATE TRIGGER folder_delete_notes_on_delete " +
+        " AFTER DELETE ON " + TABLE.NOTE +
+        " BEGIN" +
+        "  DELETE FROM " + TABLE.NOTE +
+        "   WHERE " + NoteColumns.PARENT_ID + "=old." + NoteColumns.ID + ";" +
+        " END";
+
+    /**
+     * Move notes belong to folder which has been moved to trash folder
+     */
+    private static final String FOLDER_MOVE_NOTES_ON_TRASH_TRIGGER =
+        "CREATE TRIGGER folder_move_notes_on_trash " +
+        " AFTER UPDATE ON " + TABLE.NOTE +
+        " WHEN new." + NoteColumns.PARENT_ID + "=" + Notes.ID_TRASH_FOLER +
+        " BEGIN" +
+        "  UPDATE " + TABLE.NOTE +
+        "   SET " + NoteColumns.PARENT_ID + "=" + Notes.ID_TRASH_FOLER +
+        "  WHERE " + NoteColumns.PARENT_ID + "=old." + NoteColumns.ID + ";" +
+        " END";
+
+    public NotesDatabaseHelper(Context context) {
+        super(context, DB_NAME, null, DB_VERSION);
+    }
+
+    public void createNoteTable(SQLiteDatabase db) {
+        db.execSQL(CREATE_NOTE_TABLE_SQL);
+        reCreateNoteTableTriggers(db);
+        createSystemFolder(db);
+        Log.d(TAG, "note table has been created");
+    }
+
+    private void reCreateNoteTableTriggers(SQLiteDatabase db) {
+        db.execSQL("DROP TRIGGER IF EXISTS increase_folder_count_on_update");
+        db.execSQL("DROP TRIGGER IF EXISTS decrease_folder_count_on_update");
+        db.execSQL("DROP TRIGGER IF EXISTS decrease_folder_count_on_delete");
+        db.execSQL("DROP TRIGGER IF EXISTS delete_data_on_delete");
+        db.execSQL("DROP TRIGGER IF EXISTS increase_folder_count_on_insert");
+        db.execSQL("DROP TRIGGER IF EXISTS folder_delete_notes_on_delete");
+        db.execSQL("DROP TRIGGER IF EXISTS folder_move_notes_on_trash");
+
+        db.execSQL(NOTE_INCREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER);
+        db.execSQL(NOTE_DECREASE_FOLDER_COUNT_ON_UPDATE_TRIGGER);
+        db.execSQL(NOTE_DECREASE_FOLDER_COUNT_ON_DELETE_TRIGGER);
+        db.execSQL(NOTE_DELETE_DATA_ON_DELETE_TRIGGER);
+        db.execSQL(NOTE_INCREASE_FOLDER_COUNT_ON_INSERT_TRIGGER);
+        db.execSQL(FOLDER_DELETE_NOTES_ON_DELETE_TRIGGER);
+        db.execSQL(FOLDER_MOVE_NOTES_ON_TRASH_TRIGGER);
+    }
+
+    private void createSystemFolder(SQLiteDatabase db) {
+        ContentValues values = new ContentValues();
+
+        /**
+         * call record foler for call notes
+         */
+        values.put(NoteColumns.ID, Notes.ID_CALL_RECORD_FOLDER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+
+        /**
+         * root folder which is default folder
+         */
+        values.clear();
+        values.put(NoteColumns.ID, Notes.ID_ROOT_FOLDER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+
+        /**
+         * temporary folder which is used for moving note
+         */
+        values.clear();
+        values.put(NoteColumns.ID, Notes.ID_TEMPARAY_FOLDER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+
+        /**
+         * create trash folder
+         */
+        values.clear();
+        values.put(NoteColumns.ID, Notes.ID_TRASH_FOLER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+    }
+
+    public void createDataTable(SQLiteDatabase db) {
+        db.execSQL(CREATE_DATA_TABLE_SQL);
+        reCreateDataTableTriggers(db);
+        db.execSQL(CREATE_DATA_NOTE_ID_INDEX_SQL);
+        Log.d(TAG, "data table has been created");
+    }
+
+    private void reCreateDataTableTriggers(SQLiteDatabase db) {
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_insert");
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_update");
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_content_on_delete");
+
+        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_INSERT_TRIGGER);
+        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_UPDATE_TRIGGER);
+        db.execSQL(DATA_UPDATE_NOTE_CONTENT_ON_DELETE_TRIGGER);
+    }
+
+    static synchronized NotesDatabaseHelper getInstance(Context context) {
+        if (mInstance == null) {
+            mInstance = new NotesDatabaseHelper(context);
+        }
+        return mInstance;
+    }
+
+    @Override
+    public void onCreate(SQLiteDatabase db) {
+        createNoteTable(db);
+        createDataTable(db);
+    }
+
+    @Override
+    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
+        boolean reCreateTriggers = false;
+        boolean skipV2 = false;
+
+        if (oldVersion == 1) {
+            upgradeToV2(db);
+            skipV2 = true; // this upgrade including the upgrade from v2 to v3
+            oldVersion++;
+        }
+
+        if (oldVersion == 2 && !skipV2) {
+            upgradeToV3(db);
+            reCreateTriggers = true;
+            oldVersion++;
+        }
+
+        if (oldVersion == 3) {
+            upgradeToV4(db);
+            oldVersion++;
+        }
+
+        if (reCreateTriggers) {
+            reCreateNoteTableTriggers(db);
+            reCreateDataTableTriggers(db);
+        }
+
+        if (oldVersion != newVersion) {
+            throw new IllegalStateException("Upgrade notes database to version " + newVersion
+                    + "fails");
+        }
+    }
+
+    private void upgradeToV2(SQLiteDatabase db) {
+        db.execSQL("DROP TABLE IF EXISTS " + TABLE.NOTE);
+        db.execSQL("DROP TABLE IF EXISTS " + TABLE.DATA);
+        createNoteTable(db);
+        createDataTable(db);
+    }
+
+    private void upgradeToV3(SQLiteDatabase db) {
+        // drop unused triggers
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_modified_date_on_insert");
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_modified_date_on_delete");
+        db.execSQL("DROP TRIGGER IF EXISTS update_note_modified_date_on_update");
+        // add a column for gtask id
+        db.execSQL("ALTER TABLE " + TABLE.NOTE + " ADD COLUMN " + NoteColumns.GTASK_ID
+                + " TEXT NOT NULL DEFAULT ''");
+        // add a trash system folder
+        ContentValues values = new ContentValues();
+        values.put(NoteColumns.ID, Notes.ID_TRASH_FOLER);
+        values.put(NoteColumns.TYPE, Notes.TYPE_SYSTEM);
+        db.insert(TABLE.NOTE, null, values);
+    }
+
+    private void upgradeToV4(SQLiteDatabase db) {
+        db.execSQL("ALTER TABLE " + TABLE.NOTE + " ADD COLUMN " + NoteColumns.VERSION
+                + " INTEGER NOT NULL DEFAULT 0");
+    }
+}
diff --git a/NotesProvider.java b/NotesProvider.java
new file mode 100644
index 0000000..2962851
--- /dev/null
+++ b/NotesProvider.java
@@ -0,0 +1,395 @@
+/*
+ * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package net.micode.notes.data;
+
+
+import android.app.SearchManager;
+import android.content.ContentProvider;
+import android.content.ContentUris;
+import android.content.ContentValues;
+import android.content.Intent;
+import android.content.UriMatcher;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.net.Uri;
+import android.text.TextUtils;
+import android.util.Log;
+
+import net.micode.notes.R;
+import net.micode.notes.data.Notes.DataColumns;
+import net.micode.notes.data.Notes.NoteColumns;
+import net.micode.notes.data.NotesDatabaseHelper.TABLE;
+
+
+public class NotesProvider extends ContentProvider {
+    private static final UriMatcher mMatcher;
+
+    private NotesDatabaseHelper mHelper;
+
+    private static final String TAG = "NotesProvider";
+
+    private static final int URI_NOTE            = 1;
+    private static final int URI_NOTE_ITEM       = 2;
+    private static final int URI_DATA            = 3;
+    private static final int URI_DATA_ITEM       = 4;
+
+    private static final int URI_SEARCH          = 5;
+    private static final int URI_SEARCH_SUGGEST  = 6;
+
+    static {
+        // 创建一个UriMatcher实例，用于匹配URI。NO_MATCH是初始值，表示没有匹配的URI。
+        mMatcher = new UriMatcher(UriMatcher.NO_MATCH);
+        // 添加一个URI匹配规则，用于匹配单个note的URI。
+        // 例如，content://com.example.notes.provider/note 会匹配到URI_NOTE。
+        mMatcher.addURI(Notes.AUTHORITY, "note", URI_NOTE);
+        // 添加一个URI匹配规则，用于匹配特定ID的note的URI。
+        // 例如，content://com.example.notes.provider/note/1 会匹配到URI_NOTE_ITEM。
+        // 这里的#是一个通配符，表示任意数字（即note的ID）。
+        mMatcher.addURI(Notes.AUTHORITY, "note/#", URI_NOTE_ITEM);
+        // 添加一个URI匹配规则，用于匹配data表的所有数据。
+        // 例如，content://com.example.notes.provider/data 会匹配到URI_DATA。
+        mMatcher.addURI(Notes.AUTHORITY, "data", URI_DATA);
+        // 添加一个URI匹配规则，用于匹配特定ID的data项的URI。
+        // 例如，content://com.example.notes.provider/data/1 会匹配到URI_DATA_ITEM。
+        // 同样，#是一个通配符，表示data项的ID。
+        mMatcher.addURI(Notes.AUTHORITY, "data/#", URI_DATA_ITEM);
+        // 添加一个URI匹配规则，用于处理搜索请求。
+        // 例如，content://com.example.notes.provider/search 可能会触发搜索操作。
+        mMatcher.addURI(Notes.AUTHORITY, "search", URI_SEARCH);
+        // 添加两个URI匹配规则，用于处理搜索建议。
+        // 第一个规则匹配基本的搜索建议URI，如 content://com.example.notes.provider/search_suggest_query。
+        // 第二个规则匹配带有额外路径段的搜索建议URI，这通常用于处理查询参数或特定类型的建议。
+        // 例如，content://com.example.notes.provider/search_suggest_query/some_query_parameters
+        mMatcher.addURI(Notes.AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY, URI_SEARCH_SUGGEST);
+        mMatcher.addURI(Notes.AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY + "/*", URI_SEARCH_SUGGEST);
+        // 注意：在实际应用中，第二个规则可能需要根据具体需求进行调整，
+        // 因为"/*"会匹配任何路径段，这可能导致意外的匹配。
+        // 如果搜索建议URI不需要额外的路径段，则可能不需要第二个规则。
+    }
+
+    /**
+     * x'0A' represents the '\n' character in sqlite. For title and content in the search result,
+     * we will trim '\n' and white space in order to show more information.
+     */
+    // 定义搜索建议查询的投影，即指定从数据库查询哪些列并如何格式化它们
+    private static final String NOTES_SEARCH_PROJECTION =
+            // 返回note的ID，通常用于在点击搜索建议时定位具体的note
+            NoteColumns.ID + "," +
+                    // 将note的ID作为Intent的额外数据返回，以便在点击搜索建议时传递
+                    NoteColumns.ID + " AS " + SearchManager.SUGGEST_COLUMN_INTENT_EXTRA_DATA + "," +
+                    // 去除snippet中的换行符（\n，在SQL中用x'0A'表示），并修剪空格，作为第一条搜索建议文本返回
+                    "TRIM(REPLACE(" + NoteColumns.SNIPPET + ", x'0A','')) AS " + SearchManager.SUGGEST_COLUMN_TEXT_1 + "," +
+                    // 注意：这里重复了与TEXT_1相同的逻辑，通常TEXT_2用于提供额外的文本信息，但在这个例子中似乎是多余的
+                    "TRIM(REPLACE(" + NoteColumns.SNIPPET + ", x'0A','')) AS " + SearchManager.SUGGEST_COLUMN_TEXT_2 + "," +
+                    // 将一个固定的drawable资源ID作为搜索建议的图标返回
+                    // 注意：这里使用R.drawable.search_result可能不是最佳实践，因为SQL查询通常不直接处理资源ID
+                    // 实际上，图标可能需要在搜索建议的适配器中根据返回的ID动态设置
+                    R.drawable.search_result + " AS " + SearchManager.SUGGEST_COLUMN_ICON_1 + "," +
+                    // 指定点击搜索建议时要执行的Intent动作，这里是查看note
+                    "'" + Intent.ACTION_VIEW + "' AS " + SearchManager.SUGGEST_COLUMN_INTENT_ACTION + "," +
+                    // 指定点击搜索建议时要传递给Intent的数据类型，这里是note的内容类型
+                    "'" + Notes.TextNote.CONTENT_TYPE + "' AS " + SearchManager.SUGGEST_COLUMN_INTENT_DATA;
+
+    private static String NOTES_SNIPPET_SEARCH_QUERY = "SELECT " + NOTES_SEARCH_PROJECTION
+        + " FROM " + TABLE.NOTE
+        + " WHERE " + NoteColumns.SNIPPET + " LIKE ?"
+        + " AND " + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER
+        + " AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE;
+
+    @Override
+    public boolean onCreate() {
+        mHelper = NotesDatabaseHelper.getInstance(getContext());
+        return true;
+    }
+
+    @Override
+    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
+                        String sortOrder) {
+        Cursor c = null; // 初始化Cursor为null
+        SQLiteDatabase db = mHelper.getReadableDatabase(); // 获取可读数据库实例
+        String id = null; // 用于存储从URI中提取的ID
+
+        // 根据URI匹配情况执行不同的查询
+        switch (mMatcher.match(uri)) {
+            case URI_NOTE:
+                // 查询整个Note表
+                c = db.query(TABLE.NOTE, projection, selection, selectionArgs, null, null, sortOrder);
+                break;
+
+            case URI_NOTE_ITEM:
+                // 根据URI中的ID查询特定的Note项
+                id = uri.getPathSegments().get(1);
+                c = db.query(TABLE.NOTE, projection, NoteColumns.ID + "=" + id + parseSelection(selection),
+                        selectionArgs, null, null, sortOrder);
+                break;
+
+            case URI_DATA:
+                // 查询整个Data表
+                c = db.query(TABLE.DATA, projection, selection, selectionArgs, null, null, sortOrder);
+                break;
+
+            case URI_DATA_ITEM:
+                // 根据URI中的ID查询特定的Data项
+                id = uri.getPathSegments().get(1);
+                c = db.query(TABLE.DATA, projection, DataColumns.ID + "=" + id + parseSelection(selection),
+                        selectionArgs, null, null, sortOrder);
+                break;
+
+            case URI_SEARCH:
+            case URI_SEARCH_SUGGEST:
+                // 对于搜索URI，不允许指定sortOrder, selection, selectionArgs, 或 projection
+                if (sortOrder != null || projection != null) {
+                    throw new IllegalArgumentException("不支持的查询参数，对于搜索URI不应指定sortOrder, selection, selectionArgs, 或 projection");
+                }
+
+                // 从URI中提取搜索字符串
+                String searchString = null;
+                if (mMatcher.match(uri) == URI_SEARCH_SUGGEST) {
+                    // 对于搜索建议URI，从路径段中获取搜索词
+                    if (uri.getPathSegments().size() > 1) {
+                        searchString = uri.getPathSegments().get(1);
+                    }
+                } else {
+                    // 对于普通搜索URI，从查询参数中获取搜索词
+                    searchString = uri.getQueryParameter("pattern");
+                }
+
+                // 如果没有搜索字符串，则返回null
+                if (TextUtils.isEmpty(searchString)) {
+                    return null;
+                }
+
+                // 准备并执行搜索查询
+                try {
+                    searchString = String.format("%%%s%%", searchString); // 添加通配符
+                    c = db.rawQuery(NOTES_SNIPPET_SEARCH_QUERY, new String[]{searchString}); // 使用预定义的搜索查询
+                } catch (IllegalStateException ex) {
+                    Log.e(TAG, "执行搜索查询时发生异常: " + ex.toString());
+                }
+                break;
+
+            default:
+                // 如果URI不匹配任何已知模式，则抛出异常
+                throw new IllegalArgumentException("未知的URI: " + uri);
+        }
+        // 如果查询成功，则为Cursor设置通知URI
+        if (c != null) {
+            c.setNotificationUri(getContext().getContentResolver(), uri);
+        }
+        // 返回查询结果的Cursor
+        return c;
+    }
+
+    @Override
+    /**
+     * 向数据库中插入数据。
+     * 根据提供的URI决定向哪个表中插入数据，并使用ContentValues对象中的值作为插入的数据。
+     *
+     * @param uri      指定要插入数据的表的URI。
+     * @param values   包含要插入数据的ContentValues对象。
+     * @return         返回包含新插入数据ID的Uri，但实际上这个方法的当前实现并没有返回Uri，需要补充。
+     * @throws IllegalArgumentException 如果提供的URI未知。
+     */
+    public Uri insert(Uri uri, ContentValues values) {
+        // 获取数据库的可写实例
+        SQLiteDatabase db = mHelper.getWritableDatabase();
+
+        // 初始化ID变量，这些变量可能用于记录不同表中插入的ID，但在这个例子中有些冗余
+        long dataId = 0, noteId = 0, insertedId = 0;
+
+        // 使用URI匹配器来确定URI对应的表
+        switch (mMatcher.match(uri)) {
+            // 如果URI匹配到的是笔记表的URI
+            case URI_NOTE:
+                // 向笔记表中插入数据，并获取新插入行的ID
+                // 假设TABLE.NOTE是数据库中笔记表的名称
+                // values包含了要插入的列和值
+                // null表示没有特定的列名列表，将插入values中所有的列
+                insertedId = noteId = db.insert(TABLE.NOTE, null, values);
+                // 注意：这里noteId和insertedId被设置为相同的值，但在这个方法的上下文中，noteId可能并不需要
+                break;
+
+            // 如果URI匹配到的是数据表的URI
+            case URI_DATA:
+                // 检查values中是否包含笔记ID（DataColumns.NOTE_ID），因为数据通常与某个笔记相关联
+                if (values.containsKey(DataColumns.NOTE_ID)) {
+                    // 从values中获取笔记ID
+                    noteId = values.getAsLong(DataColumns.NOTE_ID);
+                    // 注意：尽管获取了noteId，但在本例中，它并未被用于插入操作，除非有额外的逻辑需要它
+                } else {
+                    // 如果没有提供笔记ID，则记录一条日志，指出数据格式错误
+                    Log.d(TAG, "Wrong data format without note id:" + values.toString());
+                }
+                // 向数据表中插入数据，并获取新插入行的ID
+                // 假设TABLE.DATA是数据库中数据表的名称
+                insertedId = dataId = db.insert(TABLE.DATA, null, values);
+                // 同样，dataId和insertedId被设置为相同的值，但在这个上下文中，dataId可能并不需要
+                break;
+
+            // 如果URI不匹配任何已知类型，则抛出异常
+            default:
+                throw new IllegalArgumentException("Unknown URI " + uri);
+        }
+
+        // 注释：这里实际上应该返回一个Uri，该Uri包含新插入数据的ID，以便客户端可以查询或更新这条数据。
+        // 然而，当前的实现并没有这样做。为了遵循ContentResolver的约定，你需要构建并返回一个Uri。
+        // 例如，你可以使用Uri.withAppendedPath()方法，结合一个基础URI和新插入的ID来构建返回的Uri。
+
+        // 注意：由于这个方法的当前签名是返回Uri，但实现中并没有返回任何Uri，因此你需要在switch语句之后添加相应的逻辑来返回Uri。
+        // 这里只是提供了注释说明，实际实现将取决于你的应用程序的URI设计和需求。
+
+        // 假设这里我们返回一个null（这通常不是一个好主意，因为它违反了方法的签名），
+        // 但你应该用实际的Uri替换它。
+        return null; // 临时返回null，实际应返回包含新ID的Uri
+    }
+        // Notify the note uri
+        if (noteId > 0) {
+            getContext().getContentResolver().notifyChange(
+                    ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId), null);
+        }
+
+        // Notify the data uri
+        if (dataId > 0) {
+            getContext().getContentResolver().notifyChange(
+                    ContentUris.withAppendedId(Notes.CONTENT_DATA_URI, dataId), null);
+        }
+
+        return ContentUris.withAppendedId(uri, insertedId);
+    }
+
+    @Override
+    public int delete(Uri uri, String selection, String[] selectionArgs) {
+        int count = 0;
+        String id = null;
+        SQLiteDatabase db = mHelper.getWritableDatabase();
+        boolean deleteData = false;
+        switch (mMatcher.match(uri)) {
+            case URI_NOTE:
+                selection = "(" + selection + ") AND " + NoteColumns.ID + ">0 ";
+                count = db.delete(TABLE.NOTE, selection, selectionArgs);
+                break;
+            case URI_NOTE_ITEM:
+                id = uri.getPathSegments().get(1);
+                /**
+                 * ID that smaller than 0 is system folder which is not allowed to
+                 * trash
+                 */
+                long noteId = Long.valueOf(id);
+                if (noteId <= 0) {
+                    break;
+                }
+                count = db.delete(TABLE.NOTE,
+                        NoteColumns.ID + "=" + id + parseSelection(selection), selectionArgs);
+                break;
+            case URI_DATA:
+                count = db.delete(TABLE.DATA, selection, selectionArgs);
+                deleteData = true;
+                break;
+            case URI_DATA_ITEM:
+                id = uri.getPathSegments().get(1);
+                count = db.delete(TABLE.DATA,
+                        DataColumns.ID + "=" + id + parseSelection(selection), selectionArgs);
+                deleteData = true;
+                break;
+            default:
+                throw new IllegalArgumentException("Unknown URI " + uri);
+        }
+        if (count > 0) {
+            if (deleteData) {
+                getContext().getContentResolver().notifyChange(Notes.CONTENT_NOTE_URI, null);
+            }
+            getContext().getContentResolver().notifyChange(uri, null);
+        }
+        return count;
+    }
+
+    @Override
+    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
+        int count = 0;
+        String id = null;
+        SQLiteDatabase db = mHelper.getWritableDatabase();
+        boolean updateData = false;
+        switch (mMatcher.match(uri)) {
+            case URI_NOTE:
+                increaseNoteVersion(-1, selection, selectionArgs);
+                count = db.update(TABLE.NOTE, values, selection, selectionArgs);
+                break;
+            case URI_NOTE_ITEM:
+                id = uri.getPathSegments().get(1);
+                increaseNoteVersion(Long.valueOf(id), selection, selectionArgs);
+                count = db.update(TABLE.NOTE, values, NoteColumns.ID + "=" + id
+                        + parseSelection(selection), selectionArgs);
+                break;
+            case URI_DATA:
+                count = db.update(TABLE.DATA, values, selection, selectionArgs);
+                updateData = true;
+                break;
+            case URI_DATA_ITEM:
+                id = uri.getPathSegments().get(1);
+                count = db.update(TABLE.DATA, values, DataColumns.ID + "=" + id
+                        + parseSelection(selection), selectionArgs);
+                updateData = true;
+                break;
+            default:
+                throw new IllegalArgumentException("Unknown URI " + uri);
+        }
+
+        if (count > 0) {
+            if (updateData) {
+                getContext().getContentResolver().notifyChange(Notes.CONTENT_NOTE_URI, null);
+            }
+            getContext().getContentResolver().notifyChange(uri, null);
+        }
+        return count;
+    }
+
+    private String parseSelection(String selection) {
+        return (!TextUtils.isEmpty(selection) ? " AND (" + selection + ')' : "");
+    }
+
+    private void increaseNoteVersion(long id, String selection, String[] selectionArgs) {
+        StringBuilder sql = new StringBuilder(120);
+        sql.append("UPDATE ");
+        sql.append(TABLE.NOTE);
+        sql.append(" SET ");
+        sql.append(NoteColumns.VERSION);
+        sql.append("=" + NoteColumns.VERSION + "+1 ");
+
+        if (id > 0 || !TextUtils.isEmpty(selection)) {
+            sql.append(" WHERE ");
+        }
+        if (id > 0) {
+            sql.append(NoteColumns.ID + "=" + String.valueOf(id));
+        }
+        if (!TextUtils.isEmpty(selection)) {
+            String selectString = id > 0 ? parseSelection(selection) : selection;
+            for (String args : selectionArgs) {
+                selectString = selectString.replaceFirst("\\?", args);
+            }
+            sql.append(selectString);
+        }
+
+        mHelper.getWritableDatabase().execSQL(sql.toString());
+    }
+
+    @Override
+    public String getType(Uri uri) {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+}
diff --git a/注释 b/注释
new file mode 100644
index 0000000..66dc905
--- /dev/null
+++ b/注释
@@ -0,0 +1 @@
+undefined
\ No newline at end of file