Consuming Rest API- Query Parameter - Passing Map<String, List<String>>. Special Characters gets added

Question

We are a consumer of a Rest API, where we are passing query parameters. We are using Map<String, List>. But we call the API, our producer is getting some special characters for our values. For ex-

List queryParamters = new ArrayList(); queryParameters.add("ABC");

final Map<String, List> finalMap = new HashMap<>();

finalMap.put("column", Collections.singletonList(queryParamters+""));

when we call our API, our producer gets "GET /server-url/product?column=%5ABC%5D HTTP/1.1" but our expectation is to send them ABC not %5ABC%5D.

Can we enforce not to add special characters and our producer gets what we expect?

Answer 1

There's nothing wrong with the URI, it is just being encoded.

The %5B and %5D characters you are getting is because you are passing an ArrayList object as a query parameter. If your URI was not encoded, it would look like this:

GET /server-url/product?column=[ABC] HTTP/1.1

If the column parameter has just one value (as the example you gave), use a String object (not an ArrayList). The result would be like this:

GET /server-url/product?column=ABC HTTP/1.1

But if you really need to specify a list of values as URL parameters (and be able to receive them as a list in the backend side), I would recommend you to repeat the parameters, like this:

GET /server-url/product?column=ABC&column=BCD HTTP/1.1