Developing Java Applications with Spring and Spring Boot

How to do it...

1. First, let's create a new package called formatters in the src/main/java/com/example/bookpub directory from the root of our project
2. Next, we will create the Formatter implementation called BookFormatter in our newly created package directory from the root of our project with the following content:

public class BookFormatter implements Formatter<Book> { 
  private BookRepository repository; 
  public BookFormatter(BookRepository repository) { 
    this.repository= repository; 
  } 
  @Override 
  public Book parse(String bookIdentifier, Locale locale)        throws ParseException {          Book book = repository.findBookByIsbn(bookIdentifier);          return book != null ? book :          repository.findById(Long.valueOf(bookIdentifier)) .get(); } @Override public String ...