How to convert map to url query string?

Question

Do you know of any utility class/library, that can convert Map into URL-friendly query string?

Example:

I have a map:

\"param1\"=12,
\"param2         


        

Answer 1

This is the solution I implemented, using Java 8 and org.apache.http.client.URLEncodedUtils. It maps the entries of the map into a list of BasicNameValuePair and then uses Apache's URLEncodedUtils to turn that into a query string.

List nameValuePairs = params.entrySet().stream()
   .map(entry -> new BasicNameValuePair(entry.getKey(), entry.getValue()))
   .collect(Collectors.toList());

URLEncodedUtils.format(nameValuePairs, Charset.forName("UTF-8"));