Question

I’m iterating on an hashtable, concatenating the string values:

    Iterator<String> it = jsonHashtableTemp.keySet().iterator();
    String json = new String("[");
    while (it.hasNext()) {
        String s = it.next();
        json = json.concat(jsonHashtableTemp.get(s).toString());
        if (it.hasNext()) {
             json = json.concat(", ");
        }
    }
    json = json.concat("]");

I would to reverse the order of the iteration .

Is it possible?

Answer 1

You are not able to do it using Iterator, but you could add it to a list and iterate it with a simple for like this:

List<String> l = new ArrayList<String>(jsonHashTableTemp.keySet());
for (int i = l.size()-1; i >= 0; i--) {
   jsonHashTableTemp.get(l.get(i));
}

And this makes sense just in case you are using some ordered Hash like LinkedHashMap as already commented.

EDIT: corrected the l.get(i) inside loop