Here is what I have using a regex split from there.

Here is what I have using a regex split from there.

Alphabetical gives: file1 file10 file2

What I'm calling "number aware" string sorting should give: file1 file2 file10

Here is what I have using a regex split from there (http://stackoverflow.com/questions/8270784/how-to-split-a-string-between-letters-and-digits-or-between-digits-and-letters ).

The code seems to work. Any cases where I could run into problem? If not any suggestions on making it simpler or more efficient.

Any help to improve the solution would be appreciated. Thanks!

Alphabetical gives:

• file1
• file10
• file2

What I'm calling "number aware" string sorting should give:

• file1
• file2
• file10

Here is what I have using a regex split from there.

The code seems to work. Any cases where I could run into problem? If not any suggestions on making it simpler or more efficient.

Thanks for the suggestions. Based on the suggestions and discussions I have changed the code to the following improved versions. I've take out //end ;) Any other suggestions? If not I'll mark rolfl's solution.

import java.util.Comparator;
import java.util.regex.Pattern;
public class NumberAwareStringComparator implements Comparator<String>{
private static Pattern BOUNDARYSPLIT = Pattern.compile("(?<=\\D)(?=\\d)|(?<=\\d)(?=\\D)");
 public int compare(String s1, String s2) {
 
 String[] s1Parts = BOUNDARYSPLIT.split(s1);
 String[] s2Parts = BOUNDARYSPLIT.split(s2);
 
 int i = 0;
 while(i < s1Parts.length && i < s2Parts.length){
 
 //if parts are the same
 if(s1Parts[i].compareTo(s2Parts[i]) == 0){
 //go to next part
 ++i;
 }else{
 //check parts are both numeric
 if(s1Parts[i].charAt(0) >= '0' && s1Parts[i].charAt(0) <= '9' 
 && s2Parts[i].charAt(0) >= '0' && s2Parts[i].charAt(0) <= '9'){
 try{
 
 int intS1 = Integer.parseInt(s1Parts[i]);
 int intS2 = Integer.parseInt(s2Parts[i]);
 
 int diff = intS1 - intS2;
 
 if(diff == 0){
 ++i;
 }else{
 return diff;
 }
 }catch(Exception ex){
 //'should' never reach but ...
 return s1Parts[i].compareTo(s2Parts[i]);
 }
 }else{
 //string compare if neither are numeric
 return s1Parts[i].compareTo(s2Parts[i]);
 }
 }
 }
 
 //Handle if one string is a prefix of the other.
 // nothing comes before something.
 if(s1.length() < s2.length()){
 return -1;
 }else if(s1.length() > s2.length()){
 return 1;
 }else{
 return 0;
 }
 
 }
 
 }