Shuffle an array in node js

Js program for Shuffle an array. Here more information.

/*
  Node JS program for
  Shuffle the array elements
*/
class Shuffling
{
	// Function which is swapping two array elements 
	// of given location
	swapElement(arr, i, j)
	{
		// Get i location element
		var temp = arr[i];
		// Set new values
		arr[i] = arr[j];
		arr[j] = temp;
	}
	// Returns the random location of array elements
	randomLocation(min, max)
	{
		// Calculate random number between given range
		return Math.floor(Math.random() * (max + 1 - min) + min);
	}
	// Function which is shuffle given array elements
	shuffleElement(arr, size)
	{
		// (i,j) indicate locations
		var j = 0;
		var i = 0;
		// Variable which is controlling the 
		// execution process of loop
		var counter = 0;
		// Loop which is shuffling random elements in array
		while (counter < size)
		{
			// Get random location of array index
			i = this.randomLocation(0, size - 1);
			j = this.randomLocation(0, size - 1);
			if (i != j)
			{
				// Swap array elements
				this.swapElement(arr, i, j);
				counter++;
			}
		}
	}
	// Function which is display array elements
	display(arr, size)
	{
		for (var i = 0; i < size; ++i)
		{
			// Disply element value
			process.stdout.write("  " + arr[i]);
		}
		process.stdout.write("\n");
	}
}

function main()
{
  	var task = new Shuffling();
	// Define array of integer elements
	var arr = [1, 0, -3, 8, 7, 3, 9, 4, 2, 5, 10, 6];
	var size = arr.length;
	// Before shuffling  array elements
	console.log(" Initial array elements");
	task.display(arr, size);
	console.log(" After Shuffle array elements");
	task.shuffleElement(arr, size);
	task.display(arr, size);
	task.shuffleElement(arr, size);
	task.display(arr, size);
	task.shuffleElement(arr, size);
	task.display(arr, size);
}
// Start program execution
main();

Output

 Initial array elements
  1  0  -3  8  7  3  9  4  2  5  10  6
 After Shuffle array elements
  2  7  10  5  0  8  3  4  1  -3  6  9
  1  5  -3  0  6  2  8  9  3  10  7  4
  3  1  -3  0  4  8  5  2  7  9  10  6