Spring Boot Integration With MySQL as a Maven Project

spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://localhost:3306/geeksforgeeks?serverTimezone=UTC&useSSL=false&autoReconnect=true
spring.datasource.username=**** 
spring.datasource.password=****

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SampleAccessingOfMysqlApplication {
    public static void main(String[] args) {
        SpringApplication.run(SampleAccessingOfMysqlApplication.class, args);
    }
}

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

// This tells Hibernate to make
// a table out of this class
@Entity 
public class Book {
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private Integer id;

    private String bookName;

    private String isbnNumber;

    public String getBookName() {
        return bookName;
    }

    public void setBookName(String bookName) {
        this.bookName = bookName;
    }

    public String getIsbnNumber() {
        return isbnNumber;
    }

    public void setIsbnNumber(String isbnNumber) {
        this.isbnNumber = isbnNumber;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }
    
}

package com.gfg;

import org.springframework.data.repository.CrudRepository;

// This will be AUTO IMPLEMENTED by Spring
// into a Bean called Book
// CRUD refers Create, Read, Update, Delete
public interface BookRepository extends CrudRepository<Book, Integer> {

}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

// This means that this 
// class is a Controller
@Controller    

// This means URL's start with /geek (after Application path)
@RequestMapping(path="/geek") 
public class BookController {
  
    // This means to get the bean called geekuserRepository
    // Which is auto-generated by Spring, we will use it
      // to handle the data
    @Autowired 
    private BookRepository bookRepository;

    // Map ONLY POST Requests
    @PostMapping(path="/addbook") 
    public @ResponseBody String addBooks (@RequestParam String bookName
            , @RequestParam String isbnNumber) {
      
        // @ResponseBody means the returned String
          // is the response, not a view name
        // @RequestParam means it is a parameter
          // from the GET or POST request
      
        Book book = new Book();
        book.setBookName(bookName);
        book.setIsbnNumber(isbnNumber);
        bookRepository.save(book);
        return "Details got Saved";
    }

    @GetMapping(path="/books")
    public @ResponseBody Iterable<Book> getAllUsers() {
        // This returns a JSON or XML with the Book
        return bookRepository.findAll();
    }
}