diff --git a/src/net/micode/notes/data/NotesDatabaseHelper.java b/src/net/micode/notes/data/NotesDatabaseHelper.java index ffe5d57..294e6fb 100644 --- a/src/net/micode/notes/data/NotesDatabaseHelper.java +++ b/src/net/micode/notes/data/NotesDatabaseHelper.java @@ -1,17 +1,18 @@ +以下是为`NotesDatabaseHelper.java`文件添加的中文注释： + +```java /* - * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net) + * 版权所有 (c) 2010-2011, MiCode 开源社区 (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 + * 根据 Apache 许可证 2.0 版（“许可证”）授权； + * 除非遵守许可证的规定，否则不得使用此文件。 + * 您可以在以下位置获取许可证的副本： * * 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. + * 除非适用法律要求或书面同意，否则根据许可证分发的软件按“原样”分发， + * 不附带任何明示或暗示的保证或条件。 + * 请参阅许可证，了解有关权限和限制的具体语言。 */ package net.micode.notes.data; @@ -26,65 +27,72 @@ import net.micode.notes.data.Notes.DataColumns; import net.micode.notes.data.Notes.DataConstants; import net.micode.notes.data.Notes.NoteColumns; - +/** + * 笔记数据库帮助类，用于创建和管理笔记数据库。 + */ public class NotesDatabaseHelper extends SQLiteOpenHelper { + // 数据库文件名 private static final String DB_NAME = "note.db"; + // 数据库版本 private static final int DB_VERSION = 4; + // 数据库表名 public interface TABLE { - public static final String NOTE = "note"; - - public static final String DATA = "data"; + public static final String NOTE = "note"; // 笔记表 + public static final String DATA = "data"; // 数据表 } + // 日志标签 private static final String TAG = "NotesDatabaseHelper"; + // 单例对象 private static NotesDatabaseHelper mInstance; + // 创建笔记表的 SQL 语句 private static final String CREATE_NOTE_TABLE_SQL = "CREATE TABLE " + TABLE.NOTE + "(" + - NoteColumns.ID + " INTEGER PRIMARY KEY," + - NoteColumns.PARENT_ID + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.ALERTED_DATE + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.BG_COLOR_ID + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.CREATED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," + - NoteColumns.HAS_ATTACHMENT + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.MODIFIED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," + - NoteColumns.NOTES_COUNT + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.SNIPPET + " TEXT NOT NULL DEFAULT ''," + - NoteColumns.TYPE + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.WIDGET_ID + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.WIDGET_TYPE + " INTEGER NOT NULL DEFAULT -1," + - NoteColumns.SYNC_ID + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.LOCAL_MODIFIED + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.ORIGIN_PARENT_ID + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.GTASK_ID + " TEXT NOT NULL DEFAULT ''," + - NoteColumns.VERSION + " INTEGER NOT NULL DEFAULT 0" + + NoteColumns.ID + " INTEGER PRIMARY KEY," + // 笔记 ID + NoteColumns.PARENT_ID + " INTEGER NOT NULL DEFAULT 0," + // 父 ID + NoteColumns.ALERTED_DATE + " INTEGER NOT NULL DEFAULT 0," + // 提醒日期 + NoteColumns.BG_COLOR_ID + " INTEGER NOT NULL DEFAULT 0," + // 背景颜色 ID + NoteColumns.CREATED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," + // 创建日期 + NoteColumns.HAS_ATTACHMENT + " INTEGER NOT NULL DEFAULT 0," + // 是否有附件 + NoteColumns.MODIFIED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," + // 修改日期 + NoteColumns.NOTES_COUNT + " INTEGER NOT NULL DEFAULT 0," + // 笔记数量 + NoteColumns.SNIPPET + " TEXT NOT NULL DEFAULT ''," + // 摘要 + NoteColumns.TYPE + " INTEGER NOT NULL DEFAULT 0," + // 类型 + NoteColumns.WIDGET_ID + " INTEGER NOT NULL DEFAULT 0," + // 小部件 ID + NoteColumns.WIDGET_TYPE + " INTEGER NOT NULL DEFAULT -1," + // 小部件类型 + NoteColumns.SYNC_ID + " INTEGER NOT NULL DEFAULT 0," + // 同步 ID + NoteColumns.LOCAL_MODIFIED + " INTEGER NOT NULL DEFAULT 0," + // 是否本地修改 + NoteColumns.ORIGIN_PARENT_ID + " INTEGER NOT NULL DEFAULT 0," + // 原始父 ID + NoteColumns.GTASK_ID + " TEXT NOT NULL DEFAULT ''," + // gtask ID + NoteColumns.VERSION + " INTEGER NOT NULL DEFAULT 0" + // 版本 ")"; + // 创建数据表的 SQL 语句 private static final String CREATE_DATA_TABLE_SQL = "CREATE TABLE " + TABLE.DATA + "(" + - DataColumns.ID + " INTEGER PRIMARY KEY," + - DataColumns.MIME_TYPE + " TEXT NOT NULL," + - DataColumns.NOTE_ID + " INTEGER NOT NULL DEFAULT 0," + - NoteColumns.CREATED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," + - NoteColumns.MODIFIED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," + - DataColumns.CONTENT + " TEXT NOT NULL DEFAULT ''," + - DataColumns.DATA1 + " INTEGER," + - DataColumns.DATA2 + " INTEGER," + - DataColumns.DATA3 + " TEXT NOT NULL DEFAULT ''," + - DataColumns.DATA4 + " TEXT NOT NULL DEFAULT ''," + - DataColumns.DATA5 + " TEXT NOT NULL DEFAULT ''" + + DataColumns.ID + " INTEGER PRIMARY KEY," + // 数据 ID + DataColumns.MIME_TYPE + " TEXT NOT NULL," + // MIME 类型 + DataColumns.NOTE_ID + " INTEGER NOT NULL DEFAULT 0," + // 笔记 ID + NoteColumns.CREATED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," + // 创建日期 + NoteColumns.MODIFIED_DATE + " INTEGER NOT NULL DEFAULT (strftime('%s','now') * 1000)," + // 修改日期 + DataColumns.CONTENT + " TEXT NOT NULL DEFAULT ''," + // 内容 + DataColumns.DATA1 + " INTEGER," + // 数据 1 + DataColumns.DATA2 + " INTEGER," + // 数据 2 + DataColumns.DATA3 + " TEXT NOT NULL DEFAULT ''," + // 数据 3 + DataColumns.DATA4 + " TEXT NOT NULL DEFAULT ''," + // 数据 4 + DataColumns.DATA5 + " TEXT NOT NULL DEFAULT ''" + // 数据 5 ")"; + // 创建数据表中笔记 ID 索引的 SQL 语句 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 - */ + // 当笔记移动到文件夹时增加文件夹的笔记数量的触发器 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 + @@ -94,9 +102,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " WHERE " + NoteColumns.ID + "=new." + NoteColumns.PARENT_ID + ";" + " END"; - /** - * Decrease folder's note count when move note from folder - */ + // 当笔记从文件夹移出时减少文件夹的笔记数量的触发器 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 + @@ -107,9 +113,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " AND " + NoteColumns.NOTES_COUNT + ">0" + ";" + " END"; - /** - * Increase folder's note count when insert new note to the folder - */ + // 当新笔记插入到文件夹时增加文件夹的笔记数量的触发器 private static final String NOTE_INCREASE_FOLDER_COUNT_ON_INSERT_TRIGGER = "CREATE TRIGGER increase_folder_count_on_insert " + " AFTER INSERT ON " + TABLE.NOTE + @@ -119,9 +123,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " WHERE " + NoteColumns.ID + "=new." + NoteColumns.PARENT_ID + ";" + " END"; - /** - * Decrease folder's note count when delete note from the folder - */ + // 当笔记从文件夹中删除时减少文件夹的笔记数量的触发器 private static final String NOTE_DECREASE_FOLDER_COUNT_ON_DELETE_TRIGGER = "CREATE TRIGGER decrease_folder_count_on_delete " + " AFTER DELETE ON " + TABLE.NOTE + @@ -132,9 +134,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " AND " + NoteColumns.NOTES_COUNT + ">0;" + " END"; - /** - * Update note's content when insert data with type {@link DataConstants#NOTE} - */ + // 当插入类型为笔记的数据时更新笔记内容的触发器 private static final String DATA_UPDATE_NOTE_CONTENT_ON_INSERT_TRIGGER = "CREATE TRIGGER update_note_content_on_insert " + " AFTER INSERT ON " + TABLE.DATA + @@ -145,9 +145,7 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " WHERE " + NoteColumns.ID + "=new." + DataColumns.NOTE_ID + ";" + " END"; - /** - * Update note's content when data with {@link DataConstants#NOTE} type has changed - */ + // 当类型为笔记的数据发生变化时更新笔记内容的触发器 private static final String DATA_UPDATE_NOTE_CONTENT_ON_UPDATE_TRIGGER = "CREATE TRIGGER update_note_content_on_update " + " AFTER UPDATE ON " + TABLE.DATA + @@ -158,205 +156,10 @@ public class NotesDatabaseHelper extends SQLiteOpenHelper { " WHERE " + NoteColumns.ID + "=new." + DataColumns.NOTE_ID + ";" + " END"; - /** - * Update note's content when data with {@link DataConstants#NOTE} type has deleted - */ + // 当类型为笔记的数据被删除时更新笔记内容的触发器 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"); - } -} + " UPDATE " diff --git a/src/net/micode/notes/data/NotesProvider.java b/src/net/micode/notes/data/NotesProvider.java index edb0a60..034ea97 100644 --- a/src/net/micode/notes/data/NotesProvider.java +++ b/src/net/micode/notes/data/NotesProvider.java @@ -1,22 +1,22 @@ +以下是为`NotesProvider.java`文件添加的中文注释： + +```java /* - * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net) + * 版权所有 (c) 2010-2011, MiCode 开源社区 (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 + * 根据 Apache 许可证 2.0 版（“许可证”）授权； + * 除非遵守许可证的规定，否则不得使用此文件。 + * 您可以在以下位置获取许可证的副本： * * 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. + * 除非适用法律要求或书面同意，否则根据许可证分发的软件按“原样”分发， + * 不附带任何明示或暗示的保证或条件。 + * 请参阅许可证，了解有关权限和限制的具体语言。 */ package net.micode.notes.data; - import android.app.SearchManager; import android.content.ContentProvider; import android.content.ContentUris; @@ -34,23 +34,29 @@ import net.micode.notes.data.Notes.DataColumns; import net.micode.notes.data.Notes.NoteColumns; import net.micode.notes.data.NotesDatabaseHelper.TABLE; - +/** + * 笔记内容提供者，用于管理笔记数据的访问. + */ public class NotesProvider extends ContentProvider { + // Uri 匹配器 private static final UriMatcher mMatcher; + // 数据库帮助类实例 private NotesDatabaseHelper mHelper; + // 日志标签 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; + // Uri 类型常量 + private static final int URI_NOTE = 1; // 笔记 Uri + private static final int URI_NOTE_ITEM = 2; // 单个笔记 Uri + private static final int URI_DATA = 3; // 数据 Uri + private static final int URI_DATA_ITEM = 4; // 单个数据 Uri + private static final int URI_SEARCH = 5; // 搜索 Uri + private static final int URI_SEARCH_SUGGEST = 6; // 搜索建议 Uri static { + // 初始化 Uri 匹配器 mMatcher = new UriMatcher(UriMatcher.NO_MATCH); mMatcher.addURI(Notes.AUTHORITY, "note", URI_NOTE); mMatcher.addURI(Notes.AUTHORITY, "note/#", URI_NOTE_ITEM); @@ -62,8 +68,7 @@ public class NotesProvider extends ContentProvider { } /** - * 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. + * 搜索结果的投影字符串，用于搜索查询. */ private static final String NOTES_SEARCH_PROJECTION = NoteColumns.ID + "," + NoteColumns.ID + " AS " + SearchManager.SUGGEST_COLUMN_INTENT_EXTRA_DATA + "," @@ -73,6 +78,9 @@ public class NotesProvider extends ContentProvider { + "'" + Intent.ACTION_VIEW + "' AS " + SearchManager.SUGGEST_COLUMN_INTENT_ACTION + "," + "'" + Notes.TextNote.CONTENT_TYPE + "' AS " + SearchManager.SUGGEST_COLUMN_INTENT_DATA; + /** + * 笔记摘要搜索查询字符串. + */ private static String NOTES_SNIPPET_SEARCH_QUERY = "SELECT " + NOTES_SEARCH_PROJECTION + " FROM " + TABLE.NOTE + " WHERE " + NoteColumns.SNIPPET + " LIKE ?" @@ -81,6 +89,7 @@ public class NotesProvider extends ContentProvider { @Override public boolean onCreate() { + // 获取数据库帮助类实例 mHelper = NotesDatabaseHelper.getInstance(getContext()); return true; } @@ -88,35 +97,46 @@ public class NotesProvider extends ContentProvider { @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { + // 查询结果游标 Cursor c = null; + // 获取可读数据库 SQLiteDatabase db = mHelper.getReadableDatabase(); + // 笔记 ID String id = null; switch (mMatcher.match(uri)) { case URI_NOTE: + // 查询笔记表 c = db.query(TABLE.NOTE, projection, selection, selectionArgs, null, null, sortOrder); break; case URI_NOTE_ITEM: + // 获取笔记 ID id = uri.getPathSegments().get(1); + // 查询指定笔记 c = db.query(TABLE.NOTE, projection, NoteColumns.ID + "=" + id + parseSelection(selection), selectionArgs, null, null, sortOrder); break; case URI_DATA: + // 查询数据表 c = db.query(TABLE.DATA, projection, selection, selectionArgs, null, null, sortOrder); break; case URI_DATA_ITEM: + // 获取数据 ID id = uri.getPathSegments().get(1); + // 查询指定数据 c = db.query(TABLE.DATA, projection, DataColumns.ID + "=" + id + parseSelection(selection), selectionArgs, null, null, sortOrder); break; case URI_SEARCH: case URI_SEARCH_SUGGEST: + // 检查排序、投影等参数是否为空 if (sortOrder != null || projection != null) { throw new IllegalArgumentException( "do not specify sortOrder, selection, selectionArgs, or projection" + "with this query"); } + // 获取搜索字符串 String searchString = null; if (mMatcher.match(uri) == URI_SEARCH_SUGGEST) { if (uri.getPathSegments().size() > 1) { @@ -126,12 +146,15 @@ public class NotesProvider extends ContentProvider { searchString = uri.getQueryParameter("pattern"); } + // 检查搜索字符串是否为空 if (TextUtils.isEmpty(searchString)) { return null; } try { + // 格式化搜索字符串 searchString = String.format("%%%s%%", searchString); + // 执行搜索查询 c = db.rawQuery(NOTES_SNIPPET_SEARCH_QUERY, new String[] { searchString }); } catch (IllegalStateException ex) { @@ -139,8 +162,10 @@ public class NotesProvider extends ContentProvider { } break; default: + // 抛出未知 Uri 异常 throw new IllegalArgumentException("Unknown URI " + uri); } + // 设置通知 Uri if (c != null) { c.setNotificationUri(getContext().getContentResolver(), uri); } @@ -149,157 +174,57 @@ public class NotesProvider extends ContentProvider { @Override public Uri insert(Uri uri, ContentValues values) { + // 获取可写数据库 SQLiteDatabase db = mHelper.getWritableDatabase(); + // 数据 ID long dataId = 0, noteId = 0, insertedId = 0; switch (mMatcher.match(uri)) { case URI_NOTE: + // 插入笔记 insertedId = noteId = db.insert(TABLE.NOTE, null, values); break; case URI_DATA: + // 检查数据是否包含笔记 ID if (values.containsKey(DataColumns.NOTE_ID)) { noteId = values.getAsLong(DataColumns.NOTE_ID); } else { Log.d(TAG, "Wrong data format without note id:" + values.toString()); } + // 插入数据 insertedId = dataId = db.insert(TABLE.DATA, null, values); break; default: + // 抛出未知 Uri 异常 throw new IllegalArgumentException("Unknown URI " + uri); } - // Notify the note uri + // 通知笔记 Uri if (noteId > 0) { getContext().getContentResolver().notifyChange( ContentUris.withAppendedId(Notes.CONTENT_NOTE_URI, noteId), null); } - // Notify the data uri + // 通知数据 Uri if (dataId > 0) { getContext().getContentResolver().notifyChange( ContentUris.withAppendedId(Notes.CONTENT_DATA_URI, dataId), null); } + // 返回插入的 Uri return ContentUris.withAppendedId(uri, insertedId); } @Override public int delete(Uri uri, String selection, String[] selectionArgs) { + // 删除数量 int count = 0; + // 笔记 ID String id = null; + // 获取可写数据库 SQLiteDatabase db = mHelper.getWritableDatabase(); + // 是否删除数据 boolean deleteData = false; switch (mMatcher.match(uri)) { case URI_NOTE: + // 删除笔记 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; - } - -} + count = db.delete(TABLE