Convert a String into a List, which can be printed continually to scroll the text along.

String Scroller.java

/*
Example:

---
List<String> scrolling = scroll("This is a scrolling string!", 10, 5);
int i = 0;
while (true)
{
    System.out.println(scrolling.get(i++ % scrolling.size()));
	// some delay
}
---

Your output would look as if this string was scrolling by:
"This is a scrolling string!     This is a scrolling string!     This is a scrolling string!  ...etc"
in chunks of 10:
"This is a "
"his is a s"
"is is a sc"
... etc

 */

/**
 * @param string       The string to scroll
 * @param width        The width of the scroll window
 * @param spaceBetween The gap between each repetition
 * @return A List of strings to iterate through continually
 */
public static List<String> scroll(String string, int width, int spaceBetween)
{

	List<String> list = new ArrayList<String>();

	// Validation
	// String is too short for window
	if (string.length() < width)
	{
		StringBuilder sb = new StringBuilder(string);
		while (sb.length() < width)
			sb.append(" ");
		string = sb.toString();
	}

	// Invalid width/space size
	if (width < 1)
		width = 1;
	if (spaceBetween < 0)
		spaceBetween = 0;


	// Add substrings
	for (int i = 0; i < string.length() - width; i++)
		list.add(string.substring(i, i + width));

	// Add space between repeats
	StringBuilder space = new StringBuilder();
	for (int i = 0; i < spaceBetween; ++i)
	{
		list.add(string.substring(string.length() - width + (i > width ? width : i), string.length()) + space);
		if (space.length() < width)
			space.append(" ");
	}

	// Wrap
	for (int i = 0; i < width - spaceBetween; ++i)
		list.add(string.substring(string.length() - width + spaceBetween + i, string.length()) + space + string.substring(0, i));

	// Join up
	for (int i = 0; i < spaceBetween; i++)
	{
		if (i > space.length())
			break;
		list.add(space.substring(0, space.length() - i) + string.substring(0, width - (spaceBetween > width ? width : spaceBetween) + i));
	}

	return list;
}