Parse query string such as
paramA=valueA¶mB=valueB into a map of several key-value pairs separated by '&' where key is the param name before '=' as String and value is the string after '=' as a list of String (as a query parameter may have many values).
Note: Missing the '=' sign, or missing value after '=' (e.g.
foo) will result into an empty string value.
Map with query parameter keys bound to a list with their values.
URL query string. E.g.: