Java: How to split a string by a number of characters?

Using Guava:

Iterable<String> result = Splitter.fixedLength(4).split("how are you?");
String[] parts = Iterables.toArray(result, String.class);

I think that what he wants is to have a string split into substrings of size 4. Then I would do this in a loop:

List<String> strings = new ArrayList<String>();
int index = 0;
while (index < text.length()) {
    strings.add(text.substring(index, Math.min(index + 4,text.length())));
    index += 4;
}