我是新来的Spring Boot 。因此，当我使用Postman发送get，post请求时，我面临着一个问题。我得到了零响应，即使一切似乎都很好。
我的控制器文件如下：

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.DeleteMapping;
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.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;
//import org.springframework.web.bind.annotation.*;

import com.javatechie.crud.example.entity.Product;
import com.javatechie.crud.example.service.ProductService;

@RestController
public class ProductController {
    
    @Autowired
    private ProductService service;

    @PostMapping("/addProduct")
    public Product addProduct(@RequestBody Product product) {
        return service.saveProduct(product);
    }

    @PostMapping("/addProducts")
    public List<Product> addProducts(@RequestBody List<Product> products) {
        return service.saveProductAll(products);
    }

    @GetMapping("/products")
    public List<Product> findAllProducts() {
        return service.getProductAll();
    }

    @GetMapping("/productById/{id}")
    public Product findProductById(@PathVariable int id) {
        return service.getProductById(id);
    }

    @GetMapping("/product/{name}")
    public Product findProductByName(@PathVariable String name) {
        return service.getProductByName(name);
    }

    @DeleteMapping("/delete/{id}")
    public String deleteProduct(@PathVariable int id) {
        return service.deleteProduct(id);
    }
}

我的实体类文件如下：

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

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
@Entity
@Table(name = "PRODUCT_TBL")

public class Product {
    
    @Id
    @GeneratedValue
    private int id;
    private String name;
    private int quantity;
    private double price;

}

我的服务类文件如下：

import java.util.List;

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

import com.javatechie.crud.example.entity.Product;
import com.javatechie.crud.example.repository.ProductRepository;

@Service
public class ProductService {
    
    @Autowired
    private ProductRepository repository;
    
    public Product saveProduct(Product product) {
        return repository.save(product);
    }
    
    public List<Product> saveProductAll(List<Product> products) {
        return repository.saveAll(products);
    }
    
    public List<Product> getProductAll() {
        return repository.findAll();
    }
    
    public Product getProductById(int id) {
        return repository.findById(id).orElse(null);
    }

    public Product getProductByName(String name) {
        return repository.findByName(name);
    }
    
    public String deleteProduct(int id) {
        repository.deleteById(id);
        return "Product havig id " +id +"deleted successfully";
    }
}

我的application.properties文件是：

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url = jdbc:mysql://localhost:3306/test
spring.datasource.username = root
spring.datasource.password = india
spring.jpa.show-sql = true
spring.jpa.hibernate.ddl-auto = create
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
server.port=9191

**编辑：**以下是我的repo类：

import java.util.Optional;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

import com.javatechie.crud.example.entity.Product;

@Repository
public interface ProductRepository extends JpaRepository<Product, Integer> {

    Product findByName(String name);

}

我通过 Postman 发送以下POST请求-http：//localhost：9191/addProduct
对于上述问题，我得到了以下回应- {}
对于以下GET请求，我也得到空白响应-http：//localhost：9191/products
我用的是mysql db的lombok。
请让我知道出了什么问题。