REST Based API using Spring Boot and MySQL

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

@SpringBootApplication
public class SpringBootWebApplication {

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

}

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

/**

 * Homepage controller.

 */

@Controller

public class IndexController {

    @RequestMapping("/")

    String index() {

        return "index";

    }

}

import com..entities.Product;

import com..services.ProductService;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Controller;

import org.springframework.ui.Model;

import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

/**

 * Product controller.

 */

@Controller

public class ProductController {

    private ProductService productService;

    @Autowired

    public void setProductService(ProductService productService) {

        this.productService = productService;

    }

    /**

     * List all products.

     *

     * @param model

     * @return

     */

    @RequestMapping(value = "/products", method = RequestMethod.GET)

    public String list(Model model) {

        model.addAttribute("products", productService.listAllProducts());

        System.out.println("Returning rpoducts:");

        return "products";

    }

    /**

     * View a specific product by its id.

     *

     * @param id

     * @param model

     * @return

     */

    @RequestMapping("product/{id}")

    public String showProduct(@PathVariable Integer id, Model model) {

        model.addAttribute("product", productService.getProductById(id));

        return "productshow";

    }

    @RequestMapping("product/edit/{id}")

    public String edit(@PathVariable Integer id, Model model) {

        model.addAttribute("product", productService.getProductById(id));

        return "productform";

    }

    /**

     * New product.

     *

     * @param model

     * @return

     */

    @RequestMapping("product/new")

    public String newProduct(Model model) {

        model.addAttribute("product", new Product());

        return "productform";

    }

    /**

     * Save product to database.

     *

     * @param product

     * @return

     */

    @RequestMapping(value = "product", method = RequestMethod.POST)

    public String saveProduct(Product product) {

        productService.saveProduct(product);

        return "redirect:/product/" + product.getId();

    }

    /**

     * Delete product by its id.

     *

     * @param id

     * @return

     */

    @RequestMapping("product/delete/{id}")

    public String delete(@PathVariable Integer id) {

        productService.deleteProduct(id);

        return "redirect:/products";

    }

}

import javax.persistence.Entity;

import javax.persistence.GeneratedValue;

import javax.persistence.GenerationType;

import javax.persistence.Id;

import javax.persistence.Version;

import java.math.BigDecimal;

/**

 * Product entity.

 */

@Entity

public class Product {

    @Id

    @GeneratedValue(strategy = GenerationType.AUTO)

    private Integer id;

    @Version

    private Integer version;

    private String productId;

    private String name;

    private BigDecimal price;

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public Integer getVersion() {

        return version;

    }

    public void setVersion(Integer version) {

        this.version = version;

    }

    public Integer getId() {

        return id;

    }

    public void setId(Integer id) {

        this.id = id;

    }

    public String getProductId() {

        return productId;

    }

    public void setProductId(String productId) {

        this.productId = productId;

    }

    public BigDecimal getPrice() {

        return price;

    }

    public void setPrice(BigDecimal price) {

        this.price = price;

    }

}

public interface ProductRepository extends CrudRepository<Product, Integer> {

}

public interface ProductService {

    Iterable<Product> listAllProducts();

    Product getProductById(Integer id);

    Product saveProduct(Product product);

    void deleteProduct(Integer id);

}

/**

 * Product service implement.

 */

@Service

public class ProductServiceImpl implements ProductService {

    private ProductRepository productRepository;

    @Autowired

    public void setProductRepository(ProductRepository productRepository) {

        this.productRepository = productRepository;

    }

    @Override

    public Iterable<Product> listAllProducts() {

        return productRepository.findAll();

    }

    @Override

    public Product getProductById(Integer id) {

        return productRepository.findOne(id);

    }

    @Override

    public Product saveProduct(Product product) {

        return productRepository.save(product);

    }

    @Override

    public void deleteProduct(Integer id) {

        productRepository.delete(id);

    }

}