public static StringBuilder appendZeros(StringBuilder buf,int zeros){
  for (int i=zeros; i > 0; i-=ZEROPADDING.length) {
    buf.append(ZEROPADDING,0,i < ZEROPADDING.length ? i : ZEROPADDING.length);
  }
  return buf;
}

public static StringBuilder appendZeros ( StringBuilder buf , int zeros ) { for ( int i = zeros ; i > 0 ; i -= ZEROPADDING . length ) { buf . append ( ZEROPADDING , 0 , i < ZEROPADDING . length ? i : ZEROPADDING . length ) ; } return buf ; }
append zeros to a buffer .
