问如何通过USB从web门户访问安装在android上的Sqllite DB

EN

public class ExportDB {
   final static String SAMPLE_DB_NAME = "yourdatabase";
   public static void exportDB(Context context){
        File sd = Environment.getExternalStorageDirectory();
        File data = Environment.getDataDirectory();
        FileChannel source=null;
        FileChannel destination=null;
        String currentDBPath = "/data/"+ "your.package.name" +"/databases/"+SAMPLE_DB_NAME;
        String backupDBPath = SAMPLE_DB_NAME;
        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(context, "DB Exported!", Toast.LENGTH_LONG).show();
        } catch(IOException e) {
            e.printStackTrace();
        }
    }
}