question: public List < String > extractTokens ( String queryString ) { List < String > tokens = new ArrayList < String > ( ) ; Matcher matcher = tokenPattern . matcher ( queryString ) ; while ( matcher . find ( ) ) { String origToken = matcher . group ( 1 ) ; tokens . add ( origToken ) ; } return tokens ; }
target:  Extracts all the token names in the query string  of format ${token-name} 