int读0000时显示为0，谢了下面一个转换的小程序：

public class num {	public  String getNumber(int num)	{		String result = "";		switch ((num+"").length()) {		case 1:			result = "000" + num;			break;		case 2:			result = "00" + num;			break;		case 3:			result = "0" + num;			break;		case 4:			result = "" + num;			break;	    // 此处代表编号已经超过了9999，从0重新开始		default:			result = "0000";			break;		}		return result;	}}

ArrayList
    
      list = new ArrayList
     
      ();for (int i = 1; i <= 9999; i++) {    if (String.valueOf(i).length()==1) {        list.add("000"+i);    }else if (String.valueOf(i).length()==2){        list.add("00"+i);    }else if (String.valueOf(i).length()==3){        list.add("0"+i);    }else{        list.add(String.valueOf(i));    }     }