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

Question

I tried to search online to solve this question but I didn\'t found anything.

I wrote the following abstract code to explain what I\'m asking:

String         


        

Answer 1

Quick Hack

private String[] splitByNumber(String s, int size) {
    if(s == null || size <= 0)
        return null;
    int chunks = s.length() / size + ((s.length() % size > 0) ? 1 : 0);
    String[] arr = new String[chunks];
    for(int i = 0, j = 0, l = s.length(); i < l; i += size, j++)
        arr[j] = s.substring(i, Math.min(l, i + size));
    return arr;
}

Answer 2

Using simple java primitives and loops.

private static String[] splitByNumber(String text, int number) {

        int inLength = text.length();
        int arLength = inLength / number;
        int left=inLength%number;
        if(left>0){++arLength;}
        String ar[] = new String[arLength];
            String tempText=text;
            for (int x = 0; x < arLength; ++x) {

                if(tempText.length()>number){
                ar[x]=tempText.substring(0, number);
                tempText=tempText.substring(number);
                }else{
                    ar[x]=tempText;
                }

            }


        return ar;
    }

Usage : String ar[]=splitByNumber("nalaka", 2);

Answer 3

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;
}

Answer 4

Try this solution,

public static String[]chunkStringByLength(String inputString, int numOfChar) {
    if (inputString == null || numOfChar <= 0)
        return null;
    else if (inputString.length() == numOfChar)
        return new String[]{
            inputString
        };

    int chunkLen = (int)Math.ceil(inputString.length() / numOfChar);
    String[]chunks = new String[chunkLen + 1];
    for (int i = 0; i <= chunkLen; i++) {
        int endLen = numOfChar;
        if (i == chunkLen) {
            endLen = inputString.length() % numOfChar;
        }
        chunks[i] = new String(inputString.getBytes(), i * numOfChar, endLen);
    }

    return chunks;
}

Answer 5

Here's a succinct implementation using Java8 streams:

String text = "how are you?";
final AtomicInteger counter = new AtomicInteger(0);
Collection<String> strings = text.chars()
                                    .mapToObj(i -> String.valueOf((char)i) )
                                    .collect(Collectors.groupingBy(it -> counter.getAndIncrement() / 4
                                                                ,Collectors.joining()))
                                    .values();

Output:

[how , are , you?]