responseHeaderMap.put(values[0], list);
            }
            final String[] keyValue = StringUtils.split(values[1], ":", 2);
            if (keyValue.length == 2) {
                list.add(new Pair<>(keyValue[0].trim(), keyValue[1].trim()));
            } else if (keyValue.length == 1) {
                list.add(new Pair<>(keyValue[0].trim(), StringUtil.EMPTY));
            } else {

    ListIterator<V> keyValues = new ValueForKeyIterator(key);
    Iterator<? extends V> newValues = values.iterator();

    // Replace existing values, if any.
    while (keyValues.hasNext() && newValues.hasNext()) {
      keyValues.next();
      keyValues.set(newValues.next());
    }

    // Remove remaining old values, if any.
    while (keyValues.hasNext()) {
      keyValues.next();