// BookBindingModel:
package library.bindingModels;

public class BookBindingModel {
    private String title;
    private String author;
    private double price;

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public Double getPrice() {
        return price;
    }

    public void setPrice(Double price) {
        this.price = price;
    }
}
//BookController:
package library.controllers;

import library.bindingModels.BookBindingModel;
import library.entities.Book;
import library.repositories.BookRepository;
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.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.servlet.ModelAndView;

import java.util.List;

@Controller
public class BookController {
    private final BookRepository bookRepository;

    @Autowired
    public BookController(BookRepository bookRepository) {
        this.bookRepository = bookRepository;
    }


    @GetMapping("/")
    public ModelAndView index(ModelAndView modelAndView) {
        List<Book> books = this.bookRepository.findAll();
        modelAndView.setViewName("base-layout");
        modelAndView.addObject("view", "book/index");
        modelAndView.addObject("books", books);
        return modelAndView;
    }

    @GetMapping("/create")
    public ModelAndView create(ModelAndView modelAndView) {
        modelAndView.setViewName("base-layout");
        modelAndView.addObject("view", "book/create");
        return modelAndView;
    }

    @PostMapping("/create")
    public String create(Book book) {
       this.bookRepository.saveAndFlush(book);
        return "redirect:/";
    }

    @GetMapping("/edit/{id}")
    public ModelAndView edit(@PathVariable(value = "id") Integer id, ModelAndView modelAndView) {
       Book book = this.bookRepository.findById(id).get();
       modelAndView.setViewName("base-layout");
       modelAndView.addObject("view", "book/edit");
       modelAndView.addObject("book", book);
        return modelAndView;
    }

    @PostMapping("edit/{id}")
    public String edit(@PathVariable(value = "id") Integer id, BookBindingModel bookBindingModel){
      Book bookEdit = this.bookRepository.getOne(id);
        bookEdit.setTitle(bookBindingModel.getTitle());
        bookEdit.setAuthor(bookBindingModel.getAuthor());
        bookEdit.setPrice(bookBindingModel.getPrice());

      this.bookRepository.saveAndFlush(bookEdit);
        return "redirect:/";
    }

    @GetMapping("/delete/{id}")
    public ModelAndView remove(@PathVariable(value = "id")Integer id, ModelAndView modelAndView){
        Book book = this.bookRepository.findById(id).get();
        modelAndView.setViewName("base-layout");
        modelAndView.addObject("view", "book/remove");
        modelAndView.addObject("book", book);
        return modelAndView;
    }

    @PostMapping("/delete/{id}")
    public String remove(Book book){
      this.bookRepository.delete(book);
        return "redirect:/";
    }
}
//class Book:
package library.entities;

import javax.persistence.*;
import javax.validation.constraints.Min;

@Entity
@Table(name = "books")
public class Book {
    private Integer id;
    private String title;
    private String author;
    private Double price;

    public Book() {
    }

    public Book(String title, String author, Double price) {
        this.title = title;
        this.author = author;
        this.price = price;
    }

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }
    @Column(name = "title", nullable = false)
    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }
    @Column(name = "author", nullable = false)
    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    @Column(name = "price")
    @Min(value = 1)
    public Double getPrice() {
        return price;
    }

    public void setPrice(Double price) {
        this.price = price;
    }
}
//interface BookRepository:
package library.repositories;

import library.entities.Book;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface BookRepository extends JpaRepository<Book,Integer> {

}
//application properties:
#Database Properties
spring.datasource.driverClassName = com.mysql.cj.jdbc.Driver
spring.datasource.url = jdbc:mysql://localhost:3306/book_library?useSSL=false&createDatabaseIfNotExist=true
spring.datasource.username = root
spring.datasource.password =

#JPA Properties
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect
spring.jpa.properties.hibernate.format_sql=TRUE
spring.jpa.hibernate.ddl-auto=update

#Server Properties
server.port=8080