Radix sort using integers

Question

Cany anyone help me convert my code to sort using integers and maybe using a Queue?
Thanks in advance, I appreciate it.
import java.util.*;
public class RadixSort{
  String[] input;
  int maxLength;
  public RadixSort(String[] sa){
    input = sa;
    maxLength = input[0].length();
    for (int i = 1; i < input.length; ++i){
      if (input.length() > maxLength){
maxLength = input[i].length();
public String[] sort(){
for (int i = maxLength -1; i > -1; --i){ //begin compare from the last char
Arrays.sort(input, new RadixComparator(i));
return input;
// give two or more strings as command line args
// ex. java RadixSort vouch wacky lover love banana ananas
public static void main(String[] args){
RadixSort rs = new RadixSort(args);
String[] result = rs.sort();
for (int i = 0; i < result.length; ++i){
System.out.println(result[i]);
class RadixComparator implements Comparator{
int columnNum; //start from 0
public RadixComparator(int col){
columnNum = col;
public int compare(Object o1, Object o2){
char c1, c2;
String s1 = (String)o1;
String s2 = (String)o2;
int l1 = s1.length();
int l2 = s2.length();
if (l1 < (columnNum + 1)){ //s1 too short
if (l2 < (columnNum + 1)){ //both too short
return 0;
else{
return -1;
else if (l2 < (columnNum + 1)){ //s2 too short
return 1;
else{
c1 = s1.charAt(columnNum);
c2 = s2.charAt(columnNum);
return (c1 - c2);

Answer 1

sort using integersIf your integer set only contains positive numbers, you could readily use radix sort for strings for
them. You could easily convert int[] to String[] and vice versa. If your integer set is a mix of
positives and negatives, then you would have to run radix sort twice and concatenate the
results. One for positives, and anothe for negatives -- the latter should be a reverse
radix sort because -1234 is larger than -5678.