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[Dúvida] Exceção: NullPointerException(CategoryRepository.saveAll(java.lang.Iterable)" because "this.categoryRepository" is null)

durante a pratica do desafio, encontrei a seguinte exceção:
java.lang.NullPointerException: Cannot invoke "com.example.gerenciador_pedidos.repository.CategoryRepository.saveAll(java.lang.Iterable)" because "this.categoryRepository" is null

a exceção redireciona a causa para a classe Main:

//Main

@Component
public class Main {
    @Autowired
    private ProductRepository productRepository;
    @Autowired
    private CategoryRepository categoryRepository;
   
    public void Main() {
        Category eletronics = new Category(1L, "Eletronics");
        Category tools = new Category(2L, "Tools");

        Product notebook = new Product(4500.0,"Notebook", eletronics);
        Product smartphone = new Product(2500.0, "Smartphone", eletronics);
        Product watch = new Product(750.0, "Watch", eletronics);
        Product powerScrewdriver = new Product(300.0, "Power Screwdriver", tools);

        eletronics.setProduct(List.of(notebook, smartphone, watch));
        tools.setProduct(List.of(powerScrewdriver));

        categoryRepository.saveAll(List.of(eletronics, tools));

        System.out.println("Categorias e produtos: ");
        categoryRepository.findAll().forEach(category -> {
            System.out.println("Categorias: " + category.getName());
            category.getProduct().forEach(product -> System.out.println("Produtos: " + product.getName()));
        });
     //   Requests requests = new Requests(1L, LocalDate.now());
    }
}
//modelos:
@Entity
public class Category {

    @Id
    private Long id;

    private String name;

    @OneToMany(mappedBy = "category", cascade = CascadeType.ALL)
    private List<Product> product;

    public Category(Long id, String name) {
        this.id = id;
        this.name = name;
    }

    public Long getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public List<Product> getProduct() {
        return product;
    }

    public void setProduct(List<Product> product) {
        this.product = product;
    }

    public Category() {
    }
}


@Entity
public class Product {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    @Column(nullable = false, unique = true)
    private String name;
    @Column(name = "value")
    private double price;
    @ManyToOne
    @JoinColumn(name = "category_id")
    private Category category;

    public Product(double price, String name, Category category) {
        this.price = price;
        this.name = name;
        this.category = category;
    }
    public Long getId() {
        return id;
    }
    public String getName() {
        return name;
    }
    public double getPrice() {
        return price;
    }
    public Category getCategory() {
        return category;
    }

    public Product() {
    }
}

//Repositórios:
@Repository
public interface ProductRepository extends JpaRepository<Product, Long> {}

@Repository
public interface CategoryRepository extends JpaRepository<Category, Long> {}