String.PAD_LEFT  = 0;
String.PAD_RIGHT = 1;
String.PAD_BOTH  = 2;

String.prototype.pad = function(size, pad, side) {
  var str = this, append = "", size = (size - str.length);
  var pad = ((pad != null) ? pad : " ");
  if ((typeof size != "number") || ((typeof pad != "string") || (pad == ""))) {
    throw new Error("Wrong parameters for String.pad() method.");
  }
  if (side == String.PAD_BOTH) {
    str = str.pad((Math.floor(size / 2) + str.length), pad, String.PAD_LEFT);
    return str.pad((Math.ceil(size / 2) + str.length), pad, String.PAD_RIGHT);
  }
  while ((size -= pad.length) > 0) {
    append += pad;
  }
  append += pad.substr(0, (size + pad.length));
  return ((side == String.PAD_LEFT) ? append.concat(str) : str.concat(append));
}

if(!String.trim)
{
  String.prototype.trim = function()
  {
    return this.replace(/^\s+|\s+$/, '');
  };
}