Which topicreader to use when my query id is string (like q123) instead of int (123)?

[namespace-Pt]

My queries are formatted like this:

q123    this is a query

where the query id q123 and the query content is separated with a \t. I used to use -topicreader TsvInt to read queires whose id can be converted to integer. However, it fails on the aforementioned query format, triggering the following error:

java.lang.NumberFormatException: For input string: "q123"
        at java.base/java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
        at java.base/java.lang.Integer.parseInt(Integer.java:652)
        at java.base/java.lang.Integer.valueOf(Integer.java:983)
        at io.anserini.search.topicreader.TsvIntTopicReader.read(TsvIntTopicReader.java:56)
        at io.anserini.search.topicreader.TopicReader.read(TopicReader.java:97)
        at io.anserini.search.SearchCollection.runTopics(SearchCollection.java:574)
        at io.anserini.search.SearchCollection.main(SearchCollection.java:794)
Exception in thread "main" java.lang.IllegalArgumentException: Unable to load topic reader: TsvInt
        at io.anserini.search.SearchCollection.runTopics(SearchCollection.java:577)
        at io.anserini.search.SearchCollection.main(SearchCollection.java:794)

I think the error is because q123 cannot be parsed into integer. So what is the proper topicreader to use when my query id is a unique string?