Android數據庫備份類

/**


Android數據庫備份類
*/
public class BackupTask extends AsyncTask<String, Void, Integer> implements

 CompletionListener {


// 定義常量
 public static final int BACKUP_SUCCESS = 1;
 public static final int RESTORE_SUCCESS = 2;
 public static final int BACKUP_ERROR = 3;
 public static final int RESTORE_NOFLEERROR = 4;
 public static final String COMMAND_BACKUP = "backupDatabase";
 public static final String COMMAND_RESTORE = "restroeDatabase";
 private Context mContext;
public BackupTask(Context context) {

 this.mContext = context;

}
@Override
 protected Integer doInBackground(String... params) {

 // 1,獲得數據庫路徑
 File dbFile = mContext.getDatabasePath("xxx.db");
 // 2,創建保存的數據庫的路徑
 File exportDir = new File(Environment.getExternalStorageDirectory(),
         "shopBackup");
 if (!exportDir.exists()) {
     exportDir.mkdirs();
 }
 File backup = new File(exportDir, dbFile.getName());
 // 3,檢查操作
 String command = params[0];
 if (command.equals(COMMAND_BACKUP)) {
     // 復制文件
     try {
         backup.createNewFile();
         fileCopy(dbFile, backup);
         return BACKUP_SUCCESS;
     } catch (IOException e) {
         // TODO Auto-generated catch block
         e.printStackTrace();
         return BACKUP_ERROR;
     }
 } else {
     return BACKUP_ERROR;
 }


}
private void fileCopy(File source, File dest) throws IOException {

 FileChannel inChannel = new FileInputStream(source).getChannel();
 FileChannel outChannel = new FileOutputStream(dest).getChannel();
 // FileInputStream fis = new FileInputStream(dbFile);
 // FileOutputStream fos = new FileOutputStream(backup);
 // byte buffer[] = new byte[4 * 1024];
 // while(fis.read(buffer) != -1){
 // fos.write(buffer);
 // }
 // fos.flush();
 //
 long size = inChannel.size();
 try {
     inChannel.transferTo(0, inChannel.size(), outChannel);
 } catch (IOException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
 } finally {
     if (inChannel != null) {
         inChannel.close();
     }
     if (outChannel != null) {
         outChannel.close();
     }
 }

}
@Override
 protected void onPostExecute(Integer result) {

 // TODO Auto-generated method stub
 super.onPostExecute(result);
 switch (result) {
 case BACKUP_SUCCESS:
     onBackupComplete();
     break;

 default:
     break;
 }

}
@Override
 public void onBackupComplete() {

 Log.d("backup", "ok");


}
@Override
 public void onRestoreComplete() {

 // TODO Auto-generated method stub


}
@Override
 public void onError(int errorCode) {

 // TODO Auto-generated method stub


}


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