Problem in sorting numeric string

Question

hii
i have created one method using comparator and passed a list with list of strings as argument to sort method of Collections class.The string ,which is combined a string and numeric value for example A1,A2,A11,A3 .....So i wanted the result as A1,A2,A3..A11,A12... and so on as final output.but when i print the output ,they are sorted as A1,A11,A12....A2,A3....so i learned from javadoc why those are sorted as like since comparator is using charAt() method while making override compare() method.but i am not expected this sorting for my application. i need sorting output as A1,A2,A3...A11,A12.....How to compare a string with another string both have combination of string and number using java?
if any one know the logic reply me.
i have pasted my code,if any changes have to be made only in this code,correct the code.
package sample.sorting;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
public class SortString {
     public static List<String> sort(List<String> data) {
          Collections.sort(data,new Comparator<String>(){
               public int compare(String s1,String s2) {
                    return s1.compareTo(s2)     ;
          return data;
     public static void main(String[] args) {
          List<String> sortList     = new ArrayList<String>();
          sortList.add("A1");
          sortList.add("A3");
          sortList.add("A2");
          sortList.add("A9");
          sortList.add("A11");
          sortList.add("A6");
          List<String> sort = sort(sortList);
          for(String str : sort) {
               System.out.println("STR :: "+str); // O/P : A1,A11,A2,A3,A6... but expected O/P : A1,A2,A3..A11.
}thanks in advance.
with regards
Oasisderts
Edited by: oasisdesert on Dec 29, 2009 4:15 AM

Answer 1

In the compare method of the comparator, check if two Strings have equal length, if so compare them as normal, otherwise treat them as a separate case.
e.g. uncompiled return s1.length == s2.length ? s1.compareTo(s2) : if(s1.length < s2.length) -1 else 1;Mel