MissingFormatArgumentException with square brackets on android

Question

I have this string which I'm trying to format:

String url = "http://api/doSomething.json?params%5Bemail%5D=%s"
String.format(url,email).

The idea is that it ends up looking like this:
http://api/doSomething.json?params[email]=aValue;

I'm currently getting a MissingFormatArgumentException, Format specifier: 5D exception.

Has anyone had issues with this before?

Answer 1

String.format() doesn't like the %5D placeholder - %5D has to be %5d.
Reference: http://developer.android.com/reference/java/util/Formatter.html ... if it was about placeholders.

Anyway, it seems you just want the square brackets. Therefore, change this

String url = "http://api/doSomething.json?params%5Bemail%5D=%s"

to

String url = "http://api/doSomething.json?params[email]=%s"

Answer 2

In the end i was able to resolve this using a URLEncoder.

This post was particularly helpful -> URL encoding in Android

    String queryPart = String.format(PARAM_STRING,
            email);
    return baseUrl + URLEncoder.encode(queryPart, "utf-8");