Java: how to convert HashMap to array

Question

I need to convert a HashMap to an array; could anyone show me how it\'s done?

Answer 1

@SuppressWarnings("unchecked")
    public static  E[] hashMapKeysToArray(HashMap map)
    {
        int s;
        if(map == null || (s = map.size())<1)
            return null;

        E[] temp;
        E typeHelper;
        try
        {
            Iterator> iterator = map.entrySet().iterator();
            Entry iK = iterator.next();
            typeHelper = iK.getKey();

            Object o = Array.newInstance(typeHelper.getClass(), s);
            temp = (E[]) o;

            int index = 0;
            for (Map.Entry mapEntry : map.entrySet())
            {
                temp[index++] = mapEntry.getKey();
            }
        }
        catch (Exception e)
        {
            return null;
        }
        return temp;
    }
//--------------------------------------------------------
    @SuppressWarnings("unchecked")
    public static  T[] hashMapValuesToArray(HashMap map)
    {
        int s;
        if(map == null || (s = map.size())<1)
            return null;

        T[] temp;
        T typeHelper;
        try
        {
            Iterator> iterator = map.entrySet().iterator();
            Entry iK = iterator.next();
            typeHelper = iK.getValue();

            Object o = Array.newInstance(typeHelper.getClass(), s);
            temp = (T[]) o;

            int index = 0;
            for (Map.Entry mapEntry : map.entrySet())
            {
                temp[index++] = mapEntry.getValue();
            }
        }
        catch (Exception e)
        {return null;}

        return temp;
    }