Vector as a HashMap key

Question

Hi all, I want to use Vector position as a key of hash map. Do you think that it is work? And could you mind show me some sample code. Thanks!!!

Answer 1

It'll work. Here's some code that follows. However, in my sample, I'd rather store 'user' as the key to the HashMap. Also, the code below won't allow for the list to be sorted or anything after it is added to the HashMap.
import java.util.*;
public class VectorAndHashMap
    static class Preference
        String color;
        String fontSize;
        public Preference(String _color, String _fontSize) {
            color=_color;
            fontSize=_fontSize;
        public String toString() {
            return color+"/"+fontSize;
    public static void main(String[] args)
        Object[] users = {"smith", "brown", "jones"};
        // create the Vector
        Vector v = new Vector(Arrays.asList(users));
        Object[] prefs = { new Preference("blue", "big"),     // smith's
                           new Preference("blue", "small"),   // brown's
                           new Preference("red", "medium") }; // jones's
        // create the HashMap
        HashMap hashmap = new HashMap();
        // load the HashMap
        for(int i=0; i<v.size(); i++)
            hashmap.put(new Integer(i), prefs);
// lookup index for "brown"
int j=0;
boolean found = false;
for(j=0; j<v.size(); j++) {
String user = (String)v.get(j);
if(user.equals("brown")) {
found = true;
break;
// retrieve record
if(found) {
Preference pref = (Preference)hashmap.get(new Integer(j));
System.out.println("brown's record: " + pref);