diff --git a/BackupUtils.java b/BackupUtils.java new file mode 100644 index 0000000..a6cc0f1 --- /dev/null +++ b/BackupUtils.java @@ -0,0 +1,350 @@ +/* + * 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.tool; + +import android.content.Context; +import android.database.Cursor; +import android.os.Environment; +import android.text.TextUtils; +import android.text.format.DateFormat; +import android.util.Log; + +import net.micode.notes.R; +import net.micode.notes.data.Notes; +import net.micode.notes.data.Notes.DataColumns; +import net.micode.notes.data.Notes.DataConstants; +import net.micode.notes.data.Notes.NoteColumns; + +import java.io.File; +import java.io.FileNotFoundException; +import java.io.FileOutputStream; +import java.io.IOException; +import java.io.PrintStream; + + +public class BackupUtils { + private static final String TAG = "BackupUtils"; + // Singleton stuff + private static BackupUtils sInstance; + + public static synchronized BackupUtils getInstance(Context context) { + //synchronized关键字，代表这个方法加锁，相当于不管哪一个线程（例如线程A） + //运行到这个方法时，都要检查有没有其他线程B（或者C、D等）正在用这个方法（或者该类的其他同步方法），有的话要等正在使用synchronized方法的线程B（或者C、D） + //运行完这个方法后再运行此线程A，没有的话，锁定调用者，然后直接运行 + //它包括两种方法：synchronized方法和synchronized块 + if (sInstance == null) { + //如果当前备份不存在，则新声明一个 + sInstance = new BackupUtils(context); + } + return sInstance; + } + + /** + * Following states are signs to represents backup or restore + * status + */ + // Currently, the sdcard is not mounted SD卡没有被装入手机 + public static final int STATE_SD_CARD_UNMOUONTED = 0; + // The backup file not exist 备份文件夹不存在 + public static final int STATE_BACKUP_FILE_NOT_EXIST = 1; + // The data is not well formated, may be changed by other programs 数据已被破坏，可能被修改 + public static final int STATE_DATA_DESTROIED = 2; + // Some run-time exception which causes restore or backup fails 超时异常 + public static final int STATE_SYSTEM_ERROR = 3; + // Backup or restore success 成功存储 + public static final int STATE_SUCCESS = 4; + + private TextExport mTextExport; + + private BackupUtils(Context context) {//初始化函数 + mTextExport = new TextExport(context); + } + + private static boolean externalStorageAvailable() {//外部存储功能是否可用 + return Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState()); + } + + public int exportToText() { + return mTextExport.exportToText(); + } + + public String getExportedTextFileName() { + return mTextExport.mFileName; + } + + public String getExportedTextFileDir() { + return mTextExport.mFileDirectory; + } + + private static class TextExport { + private static final String[] NOTE_PROJECTION = { + NoteColumns.ID, + NoteColumns.MODIFIED_DATE, + NoteColumns.SNIPPET, + NoteColumns.TYPE + }; + + private static final int NOTE_COLUMN_ID = 0; + + private static final int NOTE_COLUMN_MODIFIED_DATE = 1; + + private static final int NOTE_COLUMN_SNIPPET = 2; + + private static final String[] DATA_PROJECTION = { + DataColumns.CONTENT, + DataColumns.MIME_TYPE, + DataColumns.DATA1, + DataColumns.DATA2, + DataColumns.DATA3, + DataColumns.DATA4, + }; + + private static final int DATA_COLUMN_CONTENT = 0; + + private static final int DATA_COLUMN_MIME_TYPE = 1; + + private static final int DATA_COLUMN_CALL_DATE = 2; + + private static final int DATA_COLUMN_PHONE_NUMBER = 4; + + private final String [] TEXT_FORMAT; + private static final int FORMAT_FOLDER_NAME = 0; + private static final int FORMAT_NOTE_DATE = 1; + private static final int FORMAT_NOTE_CONTENT = 2; + + private Context mContext; + private String mFileName; + private String mFileDirectory; + + public TextExport(Context context) { + TEXT_FORMAT = context.getResources().getStringArray(R.array.format_for_exported_note); + mContext = context; + mFileName = ""; + mFileDirectory = ""; + } + + private String getFormat(int id) {//获取文本的组成部分 + return TEXT_FORMAT[id]; + } + + /** + * Export the folder identified by folder id to text + */ + private void exportFolderToText(String folderId, PrintStream ps) { + // Query notes belong to this folder 通过查询parent id是文件夹id的note来选出制定ID文件夹下的note + Cursor notesCursor = mContext.getContentResolver().query(Notes.CONTENT_NOTE_URI, + NOTE_PROJECTION, NoteColumns.PARENT_ID + "=?", new String[] { + folderId + }, null); + + if (notesCursor != null) { + if (notesCursor.moveToFirst()) { + do { + // Print note's last modified date ps里面保存有这份note的日期 + ps.println(String.format(getFormat(FORMAT_NOTE_DATE), DateFormat.format( + mContext.getString(R.string.format_datetime_mdhm), + notesCursor.getLong(NOTE_COLUMN_MODIFIED_DATE)))); + // Query data belong to this note + String noteId = notesCursor.getString(NOTE_COLUMN_ID); + exportNoteToText(noteId, ps);//将文件导出到text + } while (notesCursor.moveToNext()); + } + notesCursor.close(); + } + } + + /** + * Export note identified by id to a print stream + */ + private void exportNoteToText(String noteId, PrintStream ps) { + Cursor dataCursor = mContext.getContentResolver().query(Notes.CONTENT_DATA_URI, + DATA_PROJECTION, DataColumns.NOTE_ID + "=?", new String[] { + noteId + }, null); + + if (dataCursor != null) {//利用光标来扫描内容，区别为callnote和note两种，靠ps.printline输出 + if (dataCursor.moveToFirst()) { + do { + String mimeType = dataCursor.getString(DATA_COLUMN_MIME_TYPE); + if (DataConstants.CALL_NOTE.equals(mimeType)) { + // Print phone number + String phoneNumber = dataCursor.getString(DATA_COLUMN_PHONE_NUMBER); + long callDate = dataCursor.getLong(DATA_COLUMN_CALL_DATE); + String location = dataCursor.getString(DATA_COLUMN_CONTENT); + + if (!TextUtils.isEmpty(phoneNumber)) {//判断是否为空字符 + ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT), + phoneNumber)); + } + // Print call date + ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT), DateFormat + .format(mContext.getString(R.string.format_datetime_mdhm), + callDate))); + // Print call attachment location + if (!TextUtils.isEmpty(location)) { + ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT), + location)); + } + } else if (DataConstants.NOTE.equals(mimeType)) { + String content = dataCursor.getString(DATA_COLUMN_CONTENT); + if (!TextUtils.isEmpty(content)) { + ps.println(String.format(getFormat(FORMAT_NOTE_CONTENT), + content)); + } + } + } while (dataCursor.moveToNext()); + } + dataCursor.close(); + } + // print a line separator between note + try { + ps.write(new byte[] { + Character.LINE_SEPARATOR, Character.LETTER_NUMBER + }); + } catch (IOException e) { + Log.e(TAG, e.toString()); + } + } + + /** + * Note will be exported as text which is user readable + */ + public int exportToText() {//总函数，调用上面的exportFolder和exportNote + if (!externalStorageAvailable()) { + Log.d(TAG, "Media was not mounted"); + return STATE_SD_CARD_UNMOUONTED; + } + + PrintStream ps = getExportToTextPrintStream(); + if (ps == null) { + Log.e(TAG, "get print stream error"); + return STATE_SYSTEM_ERROR; + } + // First export folder and its notes 导出文件夹，就是导出里面包含的便签 + Cursor folderCursor = mContext.getContentResolver().query( + Notes.CONTENT_NOTE_URI, + NOTE_PROJECTION, + "(" + NoteColumns.TYPE + "=" + Notes.TYPE_FOLDER + " AND " + + NoteColumns.PARENT_ID + "<>" + Notes.ID_TRASH_FOLER + ") OR " + + NoteColumns.ID + "=" + Notes.ID_CALL_RECORD_FOLDER, null, null); + + if (folderCursor != null) { + if (folderCursor.moveToFirst()) { + do { + // Print folder's name + String folderName = ""; + if(folderCursor.getLong(NOTE_COLUMN_ID) == Notes.ID_CALL_RECORD_FOLDER) { + folderName = mContext.getString(R.string.call_record_folder_name); + } else { + folderName = folderCursor.getString(NOTE_COLUMN_SNIPPET); + } + if (!TextUtils.isEmpty(folderName)) { + ps.println(String.format(getFormat(FORMAT_FOLDER_NAME), folderName)); + } + String folderId = folderCursor.getString(NOTE_COLUMN_ID); + exportFolderToText(folderId, ps); + } while (folderCursor.moveToNext()); + } + folderCursor.close(); + } + + // Export notes in root's folder + //将根目录里的文件导出（由于不属于任何文件夹，因此无法通过文件夹导出来实现这一部分便签的导出） + Cursor noteCursor = mContext.getContentResolver().query( + Notes.CONTENT_NOTE_URI, + NOTE_PROJECTION, + NoteColumns.TYPE + "=" + +Notes.TYPE_NOTE + " AND " + NoteColumns.PARENT_ID + + "=0", null, null); + + if (noteCursor != null) { + if (noteCursor.moveToFirst()) { + do { + 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 + String noteId = noteCursor.getString(NOTE_COLUMN_ID); + exportNoteToText(noteId, ps); + } while (noteCursor.moveToNext()); + } + noteCursor.close(); + } + ps.close(); + + return STATE_SUCCESS; + } + + /** + * Get a print stream pointed to the file {@generateExportedTextFile} + */ + private PrintStream getExportToTextPrintStream() { + File file = generateFileMountedOnSDcard(mContext, R.string.file_path, + R.string.file_name_txt_format); + if (file == null) { + Log.e(TAG, "create file to exported failed"); + return null; + } + mFileName = file.getName(); + mFileDirectory = mContext.getString(R.string.file_path); + PrintStream ps = null; + try { + FileOutputStream fos = new FileOutputStream(file); + ps = new PrintStream(fos);//将ps输出流输出到特定的文件，目的就是导出到文件，而不是直接输出 + } catch (FileNotFoundException e) { + e.printStackTrace(); + return null; + } catch (NullPointerException e) { + e.printStackTrace(); + return null; + } + return ps; + } + } + + /** + * Generate the text file to store imported data + */ + private static File generateFileMountedOnSDcard(Context context, int filePathResId, int fileNameFormatResId) { + StringBuilder sb = new StringBuilder(); + sb.append(Environment.getExternalStorageDirectory());//外部（SD卡）的存储路径 + sb.append(context.getString(filePathResId));//文件的存储路径 + File filedir = new File(sb.toString());//filedir应该就是用来存储路径信息 + sb.append(context.getString( + fileNameFormatResId, + DateFormat.format(context.getString(R.string.format_date_ymd), + System.currentTimeMillis()))); + File file = new File(sb.toString()); + + try {//如果这些文件不存在，则新建 + if (!filedir.exists()) { + filedir.mkdir(); + } + if (!file.exists()) { + file.createNewFile(); + } + return file; + } catch (SecurityException e) { + e.printStackTrace(); + } catch (IOException e) { + e.printStackTrace(); + } +//try catch 异常处理 + return null; + } +} + +