How to unmarshall the xml data to a list of Map of Strings?

I have an xml data like this ,

I have tried to unmarshall using this code ,

public class Book { private String author; private String title; private String genre; private float price; private float publish_date; private float description; }

public class mainClass { public static void main(String[] args) throws JAXBException, IOException { unmarshall(); } public static Book unmarshall() throws JAXBException, IOException { JAXBContext context = JAXBContext.newInstance(Book.class); return (Book) context.createUnmarshaller() .unmarshal(new FileReader("./books.xml")); } }

I am getting an exception like this ,

Exception in thread "main" javax.xml.bind.UnmarshalException: unexpected element (uri:"", local:"catalog"). Expected elements are (none). I knew its because of the "catalog" entity. But i want to do this for my project

please help. Thank you