import java.util.*;

public class Map {
  private static interface Mapper<I,O> {
    public O apply(I i);
  }
  private static <I,O> List<O> map(Mapper<I,O> m, List<I> list) {
    List<O> results = new ArrayList<O>();
    for ( I i : list ) {
      results.add(m.apply(i));
    }
    return results;
  }
  public static void main(String[] args) {
    List<Integer> ints = Arrays.asList(new Integer[] {2, 3, 5});
    Mapper<Integer, String> transformer =
        // more than meets the eye
        new Mapper<Integer, String>() {
        public String apply(Integer s) {
            return ""+s+s+s;
        }
    }; 
    System.out.println(map(transformer, ints));
  }
}