Radix sort implementation, archived from here: http://www.topjavatutorial.com/java/java-programs/radix-sort-in-java/

RadixSort.java

package com.javatutorial;
 
import java.util.ArrayList;
import java.util.List;
 
public class ExampleRadixSort {
 
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        
        int[] num = {170, 45, 75, 90, 802, 2, 24, 66,23,234,3,232,44};
        
        radixsort(num);
        
        for (int h : num)
            System.out.print(h + " ");
    }
 
    public static void radixsort(int[] input) {
 
          List<Integer>[] buckets = new ArrayList[10];
          for (int i = 0; i < buckets.length; i++) {
              buckets[i] = new ArrayList<Integer>();
          }
         
          // sort
          boolean flag = false;
          int tmp = -1, divisor = 1;
          while (!flag) {
              flag = true;
            // split input between lists
            for (Integer i : input) {
              tmp = i / divisor;
              buckets[tmp % 10].add(i);
              if (flag && tmp > 0) {
                  flag = false;
              }
            }
            // empty lists into input array
            int a = 0;
            for (int b = 0; b < 10; b++) {
              for (Integer i : buckets[b]) {
                input[a++] = i;
              }
              buckets[b].clear();
            }
            // move to next digit
            divisor *= 10;
          }
        }
 
}