关于打包jar后部分代码段失效的有关问题，具体的大侠里面请

public void saveAsDay(){        SimpleDateFormat dataFormat=new SimpleDateFormat("yyyy-MM-dd'.txt'");        String sToday=dataFormat.format(new Date()).toString();        boolean hasToday=false;        try{            File dir=new File("./");            String filename[]=dir.list();            for(int i=1;i<filename.length;i++){                if(filename[i].equals(sToday))                    hasToday=true;            }            File acc=new File("./","account.txt");            acc.createNewFile();            if(hasToday){                String s,tmp="";                {                    FileReader dataReader=new FileReader(acc);                    BufferedReader readData=new BufferedReader(dataReader);                    while((s=readData.readLine())!=null)                        tmp+=(s+"\n");                    readData.close();                    dataReader.close();                    acc.delete();                    }                {                    File today=new File("./",sToday);                    FileWriter dataWriter=new FileWriter(today,true);                    BufferedWriter writeData=new BufferedWriter(dataWriter);                    writeData.write(tmp);                    writeData.close();                    dataWriter.close();                }            }            else{                acc.renameTo(new File("./",sToday));                            }                }