content: package com.bookstore;
  
  import com.bookstore.service.BookstoreService;
  import org.springframework.boot.ApplicationRunner;
  import org.springframework.boot.SpringApplication;
  import org.springframework.boot.autoconfigure.SpringBootApplication;
  import org.springframework.context.annotation.Bean;
  
  @SpringBootApplication
  public class MainApplication {
      
      private final BookstoreService bookstoreService;
  
      public MainApplication(BookstoreService bookstoreService) {
          this.bookstoreService = bookstoreService;
      }        
  
      public static void main(String[] args) {
          SpringApplication.run(MainApplication.class, args);
      }
  
      @Bean
      public ApplicationRunner init() {
          return args -> {            
              
              System.out.println("\nAdd publisher ...");
              bookstoreService.addPublisher();
              
              System.out.println("\nAdd author with books ...");
              bookstoreService.addAuthorsWithBooks();
              
              System.out.println("\nFetch author by name ...");
              bookstoreService.fetchAuthorByName();
  
              System.out.println("\nRemove a book of an author ...");
              bookstoreService.removeBookOfAuthor();
              
              System.out.println("\nRemove author (and books via cascade) ...");
              bookstoreService.removeAuthor();                       
          };
      }
  }
  