Sorting a String

Question

Hi,
I was wondering how would I sort the following String using String class methods and StringTokenizer.
For example.
Input: String a = 12hello^25hello^10hello;
Sort it chronologically
Output String a = 10hello^12hello^25hello;
Thanks in advance.

Answer 1

In Java 5.0, something like the following?
import java.util.Arrays;
import java.util.Comparator;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
public class Test {
    public static void main(String[] args) {
        String a = "12hello^25hello^10hello^100hello";
        String[] tokens = a.split("\\^");
        Arrays.sort(tokens, new Comparator<String>() {
            String regexp = "(\\d+)";
            Pattern p = Pattern.compile(regexp);
            public int compare(String s1, String s2) {
                Matcher m1 = p.matcher(s1);
                Matcher m2 = p.matcher(s2);
                if (!m1.find() || !m2.find()) {
                    return s1.compareTo(s2);
                int i1 = Integer.parseInt(m1.group(1));
                int i2 = Integer.parseInt(m2.group(1));
                if (i1 < i2) {
                    return -1;
                } else if (i1 > i2) {
                    return 1;
                } else {
                    return s1.compareTo(s2);
        StringBuilder sb = new StringBuilder();
        for (String b : tokens) {
            sb.append("^").append(b);
        String result = sb.toString().substring(1);
        System.out.println(result);
}Beware, I haven't checked this for bugs. You'd probably want to check the logic of the comparator ;-)
Cheers, Neil