gistfile1.js

function ValueFinder() {
}

ValueFinder.NotFoundError = function () {
  Error.apply(this, arguments);
};
ValueFinder.NotFoundError.prototype = new Error();

ValueFinder.prototype.find = function (array) {
  if (array.length == 0) {
    throw new ValueFinder.NotFoundError("Not Found.");
  }
  var i;
  var value = array[0];

  for (i = 1; i < array.length; i++) {
    if (this.isTarget(array[i], value)) {
      value = array[i];
    }
  }
  return value;
};

ValueFinder.prototype.isTarget = function () {
  throw new TypeError("You should override isTarget method.");
};

var arrayMinFinder = new ValueFinder();
arrayMinFinder.isTarget = function (a, b) {
  return a < b;
};

var arrayMaxFinder = new ValueFinder();
arrayMaxFinder.isTarget = function (a, b) {
  return a > b;
};

function ArrayUtils() {
  throw new TypeError("ArrayUtils is a static class.");
}

ArrayUtils.min = function (array) {
  return arrayMinFinder.find(array);
};

ArrayUtils.max = function (array) {
  return arrayMaxFinder.find(array);
};