Export database in android

I am exporting my sqllite database using this code.

 public void exportDB() {
        File sd = Environment.getExternalStorageDirectory();
        File data = Environment.getDataDirectory();
        FileChannel source = null;
        FileChannel destination = null;
        String backupDBPath = "contactsManager.db";
        String currentDBPath = "/data/" + "com.packagename"
                + "/databases/" + backupDBPath;
        System.out.println("oooooooooooooo" + currentDBPath);
        File currentDB = new File(data, currentDBPath);
        File backupDB = new File(sd, backupDBPath);
        try {
            source = new FileInputStream(currentDB).getChannel();
            destination = new FileOutputStream(backupDB).getChannel();
            destination.transferFrom(source, 0, source.size());
            source.close();
            destination.close();
             Toast.makeText(getApplicationContext(), "DB Exported!", Toast.LENGTH_LONG)
             .show();
            System.out.println("---------db exporeted");
        } catch (Exception e) {
            e.printStackTrace();
        }


    }

But I am getting a file not found exception.This is the log.

java.io.FileNotFoundException: /data/data/packagename/databases/contactsManager.db: open failed: ENOENT (No such file or directory)