DecimalFormat的用法，十进制转为二进制补0

public  static  void  main(String[] args) {
         int  a =  100 ;
         String bin = Integer.toBinaryString(a);
         System.out.println (Integer.toBinaryString (a));
         DecimalFormat df =  new  DecimalFormat( "00000000" );
         String format = df.format(Integer.valueOf(bin));
         System.out.println(format);
    }