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@ -35,13 +35,16 @@ import java.io.FileOutputStream;
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import java.io.IOException;
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import java.io.PrintStream;
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// 该类用于实现笔记的备份功能,将笔记数据导出为文本文件
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public class BackupUtils {
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// 日志标签,用于在日志中标识该类的相关信息
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private static final String TAG = "BackupUtils";
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// Singleton stuff
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// 单例模式的实例对象
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private static BackupUtils sInstance;
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// 获取 BackupUtils 的单例实例
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public static synchronized BackupUtils getInstance(Context context) {
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// 如果实例还未创建,则创建一个新的实例
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if (sInstance == null) {
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sInstance = new BackupUtils(context);
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}
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@ -49,43 +52,55 @@ public class BackupUtils {
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}
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/**
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* Following states are signs to represents backup or restore
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* status
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* 以下状态用于表示备份或恢复操作的状态
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*/
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// Currently, the sdcard is not mounted
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// 当前 SD 卡未挂载
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public static final int STATE_SD_CARD_UNMOUONTED = 0;
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// The backup file not exist
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// 备份文件不存在
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public static final int STATE_BACKUP_FILE_NOT_EXIST = 1;
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// The data is not well formated, may be changed by other programs
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// 数据格式不正确,可能被其他程序修改
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public static final int STATE_DATA_DESTROIED = 2;
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// Some run-time exception which causes restore or backup fails
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// 运行时异常导致恢复或备份失败
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public static final int STATE_SYSTEM_ERROR = 3;
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// Backup or restore success
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// 备份或恢复成功
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public static final int STATE_SUCCESS = 4;
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// 文本导出工具类的实例
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private TextExport mTextExport;
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// 私有构造函数,确保只能通过 getInstance 方法获取实例
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private BackupUtils(Context context) {
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// 初始化 TextExport 实例
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mTextExport = new TextExport(context);
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}
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// 检查外部存储是否可用
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private static boolean externalStorageAvailable() {
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// 检查外部存储的状态是否为已挂载
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return Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState());
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}
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// 将笔记数据导出为文本文件
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public int exportToText() {
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// 调用 TextExport 类的 exportToText 方法进行导出操作
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return mTextExport.exportToText();
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}
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// 获取导出的文本文件的文件名
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public String getExportedTextFileName() {
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// 返回 TextExport 类中保存的文件名
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return mTextExport.mFileName;
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}
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// 获取导出的文本文件的目录
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public String getExportedTextFileDir() {
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// 返回 TextExport 类中保存的文件目录
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return mTextExport.mFileDirectory;
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}
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// 内部类,用于实现将笔记数据导出为文本文件的具体逻辑
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private static class TextExport {
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// 查询笔记信息时使用的投影,指定要查询的列
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private static final String[] NOTE_PROJECTION = {
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NoteColumns.ID,
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NoteColumns.MODIFIED_DATE,
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@ -93,12 +108,14 @@ public class BackupUtils {
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NoteColumns.TYPE
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};
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// 笔记 ID 在投影数组中的索引
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private static final int NOTE_COLUMN_ID = 0;
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// 笔记修改日期在投影数组中的索引
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private static final int NOTE_COLUMN_MODIFIED_DATE = 1;
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// 笔记摘要在投影数组中的索引
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private static final int NOTE_COLUMN_SNIPPET = 2;
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// 查询笔记数据信息时使用的投影,指定要查询的列
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private static final String[] DATA_PROJECTION = {
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DataColumns.CONTENT,
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DataColumns.MIME_TYPE,
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@ -108,39 +125,56 @@ public class BackupUtils {
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DataColumns.DATA4,
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};
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// 笔记数据内容在投影数组中的索引
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private static final int DATA_COLUMN_CONTENT = 0;
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// 笔记数据 MIME 类型在投影数组中的索引
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private static final int DATA_COLUMN_MIME_TYPE = 1;
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// 通话记录日期在投影数组中的索引
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private static final int DATA_COLUMN_CALL_DATE = 2;
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// 电话号码在投影数组中的索引
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private static final int DATA_COLUMN_PHONE_NUMBER = 4;
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// 文本格式数组,用于格式化导出的文本内容
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private final String[] TEXT_FORMAT;
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// 文件夹名称的格式索引
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private static final int FORMAT_FOLDER_NAME = 0;
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// 笔记日期的格式索引
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private static final int FORMAT_NOTE_DATE = 1;
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// 笔记内容的格式索引
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private static final int FORMAT_NOTE_CONTENT = 2;
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// 上下文对象,用于获取资源和执行相关操作
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private Context mContext;
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// 导出的文本文件的文件名
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private String mFileName;
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// 导出的文本文件的目录
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private String mFileDirectory;
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// 构造函数,初始化 TextExport 类的实例
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public TextExport(Context context) {
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// 从资源中获取文本格式数组
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TEXT_FORMAT = context.getResources().getStringArray(R.array.format_for_exported_note);
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// 保存上下文对象
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mContext = context;
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// 初始化文件名和文件目录为空字符串
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mFileName = "";
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mFileDirectory = "";
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}
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// 根据索引获取文本格式字符串
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private String getFormat(int id) {
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// 返回文本格式数组中指定索引的字符串
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return TEXT_FORMAT[id];
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}
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/**
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* Export the folder identified by folder id to text
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* 将指定文件夹下的笔记导出为文本文件
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*
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* @param folderId 文件夹的 ID
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* @param ps 打印流,用于将导出的内容写入文件
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*/
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private void exportFolderToText(String folderId, PrintStream ps) {
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// Query notes belong to this folder
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// 查询属于该文件夹的笔记信息
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Cursor notesCursor = mContext.getContentResolver().query(Notes.CONTENT_NOTE_URI,
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NOTE_PROJECTION, NoteColumns.PARENT_ID + "=?", new String[]{
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folderId
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@ -149,23 +183,29 @@ public class BackupUtils {
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if (notesCursor != null) {
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if (notesCursor.moveToFirst()) {
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do {
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// Print note's last modified date
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// 打印笔记的最后修改日期
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ps.println(String.format(getFormat(FORMAT_NOTE_DATE), DateFormat.format(
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mContext.getString(R.string.format_datetime_mdhm),
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notesCursor.getLong(NOTE_COLUMN_MODIFIED_DATE))));
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// Query data belong to this note
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// 获取笔记的 ID
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String noteId = notesCursor.getString(NOTE_COLUMN_ID);
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// 将该笔记导出为文本
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exportNoteToText(noteId, ps);
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} while (notesCursor.moveToNext());
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}
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// 关闭游标,释放资源
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notesCursor.close();
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}
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}
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/**
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* Export note identified by id to a print stream
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* 将指定 ID 的笔记导出为文本文件
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*
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* @param noteId 笔记的 ID
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* @param ps 打印流,用于将导出的内容写入文件
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*/
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private void exportNoteToText(String noteId, PrintStream ps) {
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// 查询属于该笔记的数据信息
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Cursor dataCursor = mContext.getContentResolver().query(Notes.CONTENT_DATA_URI,
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DATA_PROJECTION, DataColumns.NOTE_ID + "=?", new String[]{
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noteId
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@ -174,62 +214,80 @@ public class BackupUtils {
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if (dataCursor != null) {
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if (dataCursor.moveToFirst()) {
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do {
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// 获取数据的 MIME 类型
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String mimeType = dataCursor.getString(DATA_COLUMN_MIME_TYPE);
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if (DataConstants.CALL_NOTE.equals(mimeType)) {
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// Print phone number
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// 如果是通话记录笔记
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// 获取电话号码
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String phoneNumber = dataCursor.getString(DATA_COLUMN_PHONE_NUMBER);
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// 获取通话日期
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long callDate = dataCursor.getLong(DATA_COLUMN_CALL_DATE);
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// 获取通话记录的位置信息
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String location = dataCursor.getString(DATA_COLUMN_CONTENT);
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if (!TextUtils.isEmpty(phoneNumber)) {
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// 如果电话号码不为空,则打印电话号码
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ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT),
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phoneNumber));
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}
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// Print call date
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// 打印通话日期
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ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT), DateFormat
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.format(mContext.getString(R.string.format_datetime_mdhm),
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callDate)));
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// Print call attachment location
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if (!TextUtils.isEmpty(location)) {
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// 如果位置信息不为空,则打印位置信息
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ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT),
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location));
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}
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} else if (DataConstants.NOTE.equals(mimeType)) {
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// 如果是普通笔记
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// 获取笔记内容
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String content = dataCursor.getString(DATA_COLUMN_CONTENT);
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if (!TextUtils.isEmpty(content)) {
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// 如果笔记内容不为空,则打印笔记内容
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ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT),
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content));
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}
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}
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} while (dataCursor.moveToNext());
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}
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// 关闭游标,释放资源
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dataCursor.close();
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}
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// print a line separator between note
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// 在笔记之间打印一个换行符
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try {
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ps.write(new byte[]{
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Character.LINE_SEPARATOR, Character.LETTER_NUMBER
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});
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} catch (IOException e) {
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// 记录异常信息
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Log.e(TAG, e.toString());
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}
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}
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/**
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* Note will be exported as text which is user readable
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* 将笔记数据导出为用户可读的文本文件
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*
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* @return 导出操作的状态码,可能的值为 STATE_SD_CARD_UNMOUONTED、STATE_SYSTEM_ERROR 或 STATE_SUCCESS
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*/
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public int exportToText() {
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// 检查外部存储是否可用
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if (!externalStorageAvailable()) {
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// 记录日志信息
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Log.d(TAG, "Media was not mounted");
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// 返回 SD 卡未挂载的状态码
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return STATE_SD_CARD_UNMOUONTED;
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}
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// 获取用于导出文本的打印流
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PrintStream ps = getExportToTextPrintStream();
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if (ps == null) {
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// 记录日志信息
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Log.e(TAG, "get print stream error");
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// 返回系统错误的状态码
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return STATE_SYSTEM_ERROR;
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}
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// First export folder and its notes
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// 首先导出文件夹及其包含的笔记
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Cursor folderCursor = mContext.getContentResolver().query(
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Notes.CONTENT_NOTE_URI,
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NOTE_PROJECTION,
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@ -240,105 +298,144 @@ public class BackupUtils {
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if (folderCursor != null) {
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if (folderCursor.moveToFirst()) {
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do {
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// Print folder's name
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// 获取文件夹名称
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String folderName = "";
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if (folderCursor.getLong(NOTE_COLUMN_ID) == Notes.ID_CALL_RECORD_FOLDER) {
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// 如果是通话记录文件夹,则从资源中获取文件夹名称
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folderName = mContext.getString(R.string.call_record_folder_name);
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} else {
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// 否则,从游标中获取文件夹摘要作为文件夹名称
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folderName = folderCursor.getString(NOTE_COLUMN_SNIPPET);
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}
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if (!TextUtils.isEmpty(folderName)) {
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// 如果文件夹名称不为空,则打印文件夹名称
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|
|
|
|
ps.println(String.format(getFormat(FORMAT_FOLDER_NAME), folderName));
|
|
|
|
|
}
|
|
|
|
|
// 获取文件夹 ID
|
|
|
|
|
String folderId = folderCursor.getString(NOTE_COLUMN_ID);
|
|
|
|
|
// 将该文件夹下的笔记导出为文本
|
|
|
|
|
exportFolderToText(folderId, ps);
|
|
|
|
|
} while (folderCursor.moveToNext());
|
|
|
|
|
}
|
|
|
|
|
// 关闭游标,释放资源
|
|
|
|
|
folderCursor.close();
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Export notes in root's folder
|
|
|
|
|
// 导出根文件夹下的笔记
|
|
|
|
|
Cursor noteCursor = mContext.getContentResolver().query(
|
|
|
|
|
Notes.CONTENT_NOTE_URI,
|
|
|
|
|
NOTE_PROJECTION,
|
|
|
|
|
NoteColumns.TYPE + "=" + +Notes.TYPE_NOTE + " AND " + NoteColumns.PARENT_ID
|
|
|
|
|
NoteColumns.TYPE + "=" + Notes.TYPE_NOTE + " AND " + NoteColumns.PARENT_ID
|
|
|
|
|
+ "=0", null, null);
|
|
|
|
|
|
|
|
|
|
if (noteCursor != null) {
|
|
|
|
|
if (noteCursor.moveToFirst()) {
|
|
|
|
|
do {
|
|
|
|
|
// 打印笔记的最后修改日期
|
|
|
|
|
ps.println(String.format(getFormat(FORMAT_NOTE_DATE), DateFormat.format(
|
|
|
|
|
mContext.getString(R.string.format_datetime_mdhm),
|
|
|
|
|
noteCursor.getLong(NOTE_COLUMN_MODIFIED_DATE))));
|
|
|
|
|
// Query data belong to this note
|
|
|
|
|
// 获取笔记的 ID
|
|
|
|
|
String noteId = noteCursor.getString(NOTE_COLUMN_ID);
|
|
|
|
|
// 将该笔记导出为文本
|
|
|
|
|
exportNoteToText(noteId, ps);
|
|
|
|
|
} while (noteCursor.moveToNext());
|
|
|
|
|
}
|
|
|
|
|
// 关闭游标,释放资源
|
|
|
|
|
noteCursor.close();
|
|
|
|
|
}
|
|
|
|
|
// 关闭打印流
|
|
|
|
|
ps.close();
|
|
|
|
|
|
|
|
|
|
// 返回导出成功的状态码
|
|
|
|
|
return STATE_SUCCESS;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/**
|
|
|
|
|
* Get a print stream pointed to the file {@generateExportedTextFile}
|
|
|
|
|
* 获取一个指向导出文本文件的打印流
|
|
|
|
|
*
|
|
|
|
|
* @return 打印流对象,如果创建文件或获取流失败,则返回 null
|
|
|
|
|
*/
|
|
|
|
|
private PrintStream getExportToTextPrintStream() {
|
|
|
|
|
// 生成一个存储在 SD 卡上的文件
|
|
|
|
|
File file = generateFileMountedOnSDcard(mContext, R.string.file_path,
|
|
|
|
|
R.string.file_name_txt_format);
|
|
|
|
|
if (file == null) {
|
|
|
|
|
// 记录日志信息
|
|
|
|
|
Log.e(TAG, "create file to exported failed");
|
|
|
|
|
// 返回 null 表示创建文件失败
|
|
|
|
|
return null;
|
|
|
|
|
}
|
|
|
|
|
// 保存文件名
|
|
|
|
|
mFileName = file.getName();
|
|
|
|
|
// 保存文件目录
|
|
|
|
|
mFileDirectory = mContext.getString(R.string.file_path);
|
|
|
|
|
PrintStream ps = null;
|
|
|
|
|
try {
|
|
|
|
|
// 创建文件输出流
|
|
|
|
|
FileOutputStream fos = new FileOutputStream(file);
|
|
|
|
|
// 创建打印流
|
|
|
|
|
ps = new PrintStream(fos);
|
|
|
|
|
} catch (FileNotFoundException e) {
|
|
|
|
|
// 打印异常堆栈信息
|
|
|
|
|
e.printStackTrace();
|
|
|
|
|
// 返回 null 表示文件未找到
|
|
|
|
|
return null;
|
|
|
|
|
} catch (NullPointerException e) {
|
|
|
|
|
// 打印异常堆栈信息
|
|
|
|
|
e.printStackTrace();
|
|
|
|
|
// 返回 null 表示空指针异常
|
|
|
|
|
return null;
|
|
|
|
|
}
|
|
|
|
|
// 返回打印流对象
|
|
|
|
|
return ps;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/**
|
|
|
|
|
* Generate the text file to store imported data
|
|
|
|
|
* 生成一个存储在 SD 卡上的文本文件,用于存储导出的数据
|
|
|
|
|
*
|
|
|
|
|
* @param context 上下文对象,用于获取资源和执行相关操作
|
|
|
|
|
* @param filePathResId 文件路径的资源 ID
|
|
|
|
|
* @param fileNameFormatResId 文件名格式的资源 ID
|
|
|
|
|
* @return 生成的文件对象,如果创建文件失败,则返回 null
|
|
|
|
|
*/
|
|
|
|
|
private static File generateFileMountedOnSDcard(Context context, int filePathResId, int fileNameFormatResId) {
|
|
|
|
|
// 创建一个 StringBuilder 对象,用于构建文件路径
|
|
|
|
|
StringBuilder sb = new StringBuilder();
|
|
|
|
|
// 添加外部存储目录
|
|
|
|
|
sb.append(Environment.getExternalStorageDirectory());
|
|
|
|
|
// 添加文件路径
|
|
|
|
|
sb.append(context.getString(filePathResId));
|
|
|
|
|
// 创建文件目录对象
|
|
|
|
|
File filedir = new File(sb.toString());
|
|
|
|
|
// 添加文件名
|
|
|
|
|
sb.append(context.getString(
|
|
|
|
|
fileNameFormatResId,
|
|
|
|
|
DateFormat.format(context.getString(R.string.format_date_ymd),
|
|
|
|
|
System.currentTimeMillis())));
|
|
|
|
|
// 创建文件对象
|
|
|
|
|
File file = new File(sb.toString());
|
|
|
|
|
|
|
|
|
|
try {
|
|
|
|
|
// 如果文件目录不存在,则创建目录
|
|
|
|
|
if (!filedir.exists()) {
|
|
|
|
|
filedir.mkdir();
|
|
|
|
|
}
|
|
|
|
|
// 如果文件不存在,则创建文件
|
|
|
|
|
if (!file.exists()) {
|
|
|
|
|
file.createNewFile();
|
|
|
|
|
}
|
|
|
|
|
// 返回创建好的文件对象
|
|
|
|
|
return file;
|
|
|
|
|
} catch (SecurityException e) {
|
|
|
|
|
// 打印安全异常信息
|
|
|
|
|
e.printStackTrace();
|
|
|
|
|
} catch (IOException e) {
|
|
|
|
|
// 打印输入输出异常信息
|
|
|
|
|
e.printStackTrace();
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// 如果出现异常,返回 null
|
|
|
|
|
return null;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|