java位数不足自动左补0

String transid=getTransid();String token = DigestUtils.sha256Hex(appid + "GZSJDQ" + transid);//token生成方式

public String getTransid(){//生成日期加8位随机数的字符串SimpleDateFormat f=new SimpleDateFormat("yyyyMMddHHmmss");String date=f.format( new Date());String transid=appid+date+getCount(new Random().nextInt(9999-1000+1)+1000).toString();return transid;}//位数不足自动左补全public String getCount(Integer i){String s=i.toString();int l=s.length();if(l<8){for(int j=0;j<8-l;j++){s="0"+s;}}else{s= s.substring(0, 7);}return s;}