Added Category entity with all related dto, service, mapper and controller.

src/main/java/mate/academy/bookstore/controller/BookController.java

@@ -6,8 +6,8 @@
 import java.util.List;
 import lombok.RequiredArgsConstructor;
 import mate.academy.bookstore.dto.book.BookDto;
-import mate.academy.bookstore.dto.book.BookRequestDto;
 import mate.academy.bookstore.dto.book.BookSearchParametersDto;
+import mate.academy.bookstore.dto.book.CreateBookRequestDto;
 import mate.academy.bookstore.service.BookService;
 import org.springframework.data.domain.Pageable;
 import org.springframework.http.HttpStatus;
@@ -29,13 +29,15 @@
 public class BookController {
     private final BookService bookService;
 
+    @PreAuthorize("hasAnyRole('USER', 'ADMIN')")
     @GetMapping
     @ResponseStatus(HttpStatus.OK)
     @Operation(summary = "Get all books", description = "Get a list of all available books")
     public List<BookDto> getAll(Pageable pageable) {
         return bookService.findAll(pageable);
     }
 
+    @PreAuthorize("hasAnyRole('USER', 'ADMIN')")
     @GetMapping("/{id}")
     @ResponseStatus(HttpStatus.OK)
     @Operation(summary = "Get a book by ID", description = "Get a book by ID, if there is one")
@@ -47,7 +49,7 @@ public BookDto getBookById(@PathVariable Long id) {
     @PostMapping
     @ResponseStatus(HttpStatus.CREATED)
     @Operation(summary = "Create a new book", description = "Create a new book with generated ID")
-    public BookDto createBook(@RequestBody @Valid BookRequestDto requestDto) {
+    public BookDto createBook(@RequestBody @Valid CreateBookRequestDto requestDto) {
         return bookService.save(requestDto);
     }
 
@@ -56,7 +58,7 @@ public BookDto createBook(@RequestBody @Valid BookRequestDto requestDto) {
     @ResponseStatus(HttpStatus.ACCEPTED)
     @Operation(summary = "Update a book by ID", description = "Update a book by its ID, if exists")
     public BookDto updateBook(@PathVariable Long id,
-                              @RequestBody @Valid BookRequestDto requestDto) {
+                              @RequestBody @Valid CreateBookRequestDto requestDto) {
         return bookService.updateById(id, requestDto);
     }
 
@@ -68,6 +70,7 @@ public void deleteBook(@PathVariable Long id) {
         bookService.delete(id);
     }
 
+    @PreAuthorize("hasAnyRole('USER', 'ADMIN')")
     @GetMapping("/search")
     @ResponseStatus(HttpStatus.OK)
     @Operation(summary = "Get a list of books by search parameters",

src/main/java/mate/academy/bookstore/controller/CategoryController.java

@@ -0,0 +1,77 @@
+package mate.academy.bookstore.controller;
+
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import jakarta.validation.Valid;
+import java.util.List;
+import lombok.RequiredArgsConstructor;
+import mate.academy.bookstore.dto.book.BookDtoWithoutCategoryIds;
+import mate.academy.bookstore.dto.category.CategoryDto;
+import mate.academy.bookstore.service.BookService;
+import mate.academy.bookstore.service.CategoryService;
+import org.springframework.data.domain.Pageable;
+import org.springframework.security.access.prepost.PreAuthorize;
+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.PutMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RequiredArgsConstructor
+@RestController
+@Tag(name = "Category management", description = "Endpoints for category management")
+@RequestMapping(value = "/categories")
+public class CategoryController {
+    private final CategoryService categoryService;
+    private final BookService bookService;
+
+    @PreAuthorize("hasRole('ADMIN')")
+    @PostMapping
+    @Operation(summary = "Create new category", description = "Create category with generated ID")
+    public CategoryDto createCategory(@RequestBody @Valid CategoryDto categoryDto) {
+        return categoryService.save(categoryDto);
+    }
+
+    @PreAuthorize("hasAnyRole('USER', 'ADMIN')")
+    @GetMapping
+    @Operation(summary = "Get all categories", description = "Get a list of existing categories")
+    public List<CategoryDto> getAll(Pageable pageable) {
+        return categoryService.findAll(pageable);
+    }
+
+    @PreAuthorize("hasAnyRole('USER', 'ADMIN')")
+    @GetMapping("/{id}")
+    @Operation(summary = "Get category by ID", description = "Get category by ID, if there is one")
+    public CategoryDto getCategoryById(@PathVariable Long id) {
+        return categoryService.getById(id);
+    }
+
+    @PreAuthorize("hasRole('ADMIN')")
+    @PutMapping("/{id}")
+    @Operation(summary = "Update category by ID", description = "Update category by ID, if exists")
+    public CategoryDto updateCategory(@PathVariable Long id,
+                                      @RequestBody @Valid CategoryDto categoryDto) {
+        return categoryService.update(id, categoryDto);
+    }
+
+    @PreAuthorize("hasRole('ADMIN')")
+    @DeleteMapping("/{id}")
+    @Operation(summary = "Delete category by ID", description = "Delete category by ID, if exists")
+    public void deleteCategory(@PathVariable Long id) {
+        categoryService.delete(id);
+    }
+
+    @PreAuthorize("hasAnyRole('USER', 'ADMIN')")
+    @GetMapping("/{id}/books")
+    @Operation(summary = "Get books by category ID",
+            description = "Get a list of books by category ID")
+    public List<BookDtoWithoutCategoryIds> getBooksByCategoryId(
+            @PathVariable Long id,
+            Pageable pageable
+    ) {
+        return bookService.getAllBookByCategoryId(id, pageable);
+    }
+}

src/main/java/mate/academy/bookstore/dto/book/BookDto.java

@@ -1,6 +1,7 @@
 package mate.academy.bookstore.dto.book;
 
 import java.math.BigDecimal;
+import java.util.Set;
 import lombok.Data;
 
 @Data
@@ -12,4 +13,5 @@ public class BookDto {
     private BigDecimal price;
     private String description;
     private String coverImage;
+    private Set<Long> categories;
 }

src/main/java/mate/academy/bookstore/dto/book/BookDtoWithoutCategoryIds.java

@@ -0,0 +1,15 @@
+package mate.academy.bookstore.dto.book;
+
+import java.math.BigDecimal;
+import lombok.Data;
+
+@Data
+public class BookDtoWithoutCategoryIds {
+    private Long id;
+    private String title;
+    private String author;
+    private String isbn;
+    private BigDecimal price;
+    private String description;
+    private String coverImage;
+}

src/main/java/mate/academy/bookstore/dto/book/BookRequestDto.java → src/main/java/mate/academy/bookstore/dto/book/CreateBookRequestDto.java

@@ -8,7 +8,7 @@
 import org.hibernate.validator.constraints.ISBN;
 
 @Data
-public class BookRequestDto {
+public class CreateBookRequestDto {
     @NotBlank
     private String title;
     @NotBlank

src/main/java/mate/academy/bookstore/dto/category/CategoryDto.java

@@ -0,0 +1,13 @@
+package mate.academy.bookstore.dto.category;
+
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.Size;
+
+public record CategoryDto(
+        Long id,
+        @NotBlank
+        @Size(min = 4, max = 24, message = "Category name must be 4 to 24 characters long")
+        String name,
+        String description
+) {
+}

src/main/java/mate/academy/bookstore/exception/DuplicateEntityException.java

@@ -0,0 +1,7 @@
+package mate.academy.bookstore.exception;
+
+public class DuplicateEntityException extends RuntimeException {
+    public DuplicateEntityException(String message) {
+        super(message);
+    }
+}

src/main/java/mate/academy/bookstore/exception/GlobalExceptionHandler.java

@@ -38,6 +38,11 @@ protected ResponseEntity<Object> handleMethodRepository(DuplicateIsbnException e
         return getResponseEntity(HttpStatus.BAD_REQUEST, ex.getMessage());
     }
 
+    @ExceptionHandler(DuplicateEntityException.class)
+    protected ResponseEntity<Object> handleMethodRepository(DuplicateEntityException ex) {
+        return getResponseEntity(HttpStatus.BAD_REQUEST, ex.getMessage());
+    }
+
     @ExceptionHandler(EntityNotFoundException.class)
     protected ResponseEntity<Object> handleMethodNotFound(EntityNotFoundException ex) {
         return getResponseEntity(HttpStatus.NOT_FOUND, ex.getMessage());

src/main/java/mate/academy/bookstore/mapper/BookMapper.java

@@ -1,17 +1,36 @@
 package mate.academy.bookstore.mapper;
 
+import java.util.Collections;
+import java.util.stream.Collectors;
 import mate.academy.bookstore.config.MapperConfig;
 import mate.academy.bookstore.dto.book.BookDto;
-import mate.academy.bookstore.dto.book.BookRequestDto;
+import mate.academy.bookstore.dto.book.BookDtoWithoutCategoryIds;
+import mate.academy.bookstore.dto.book.CreateBookRequestDto;
 import mate.academy.bookstore.model.Book;
+import mate.academy.bookstore.model.Category;
+import org.mapstruct.AfterMapping;
 import org.mapstruct.Mapper;
 import org.mapstruct.Mapping;
+import org.mapstruct.MappingTarget;
 
 @Mapper(config = MapperConfig.class)
 public interface BookMapper {
+    @Mapping(target = "categories", ignore = true)
     BookDto toDto(Book book);
 
     @Mapping(target = "id", ignore = true)
     @Mapping(target = "deleted", ignore = true)
-    Book toModel(BookRequestDto requestDto);
+    Book toEntity(CreateBookRequestDto requestDto);
+
+    BookDtoWithoutCategoryIds toDtoWithoutCategories(Book book);
+
+    @AfterMapping
+    default void setCategoryIds(@MappingTarget BookDto bookDto, Book book) {
+        if (book.getCategories() == null) {
+            bookDto.setCategories(Collections.emptySet());
+        }
+        bookDto.setCategories(book.getCategories().stream()
+                                  .map(Category::getId)
+                                  .collect(Collectors.toSet()));
+    }
 }

src/main/java/mate/academy/bookstore/mapper/CategoryMapper.java

@@ -0,0 +1,13 @@
+package mate.academy.bookstore.mapper;
+
+import mate.academy.bookstore.config.MapperConfig;
+import mate.academy.bookstore.dto.category.CategoryDto;
+import mate.academy.bookstore.model.Category;
+import org.mapstruct.Mapper;
+
+@Mapper(config = MapperConfig.class)
+public interface CategoryMapper {
+    CategoryDto toDto(Category category);
+
+    Category toEntity(CategoryDto categoryDto);
+}

src/main/java/mate/academy/bookstore/model/Book.java

@@ -2,11 +2,17 @@
 
 import jakarta.persistence.Column;
 import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
 import jakarta.persistence.GeneratedValue;
 import jakarta.persistence.GenerationType;
 import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.JoinTable;
+import jakarta.persistence.ManyToMany;
 import jakarta.persistence.Table;
 import java.math.BigDecimal;
+import java.util.HashSet;
+import java.util.Set;
 import lombok.EqualsAndHashCode;
 import lombok.Getter;
 import lombok.Setter;
@@ -15,7 +21,7 @@
 
 @Getter
 @Setter
-@EqualsAndHashCode(of = {"id", "title", "author", "isbn"})
+@EqualsAndHashCode(of = {"id", "title", "author", "isbn", "categories"})
 @Entity
 @SQLDelete(sql = "UPDATE books SET is_deleted = true WHERE id=?")
 @SQLRestriction(value = "is_deleted=false")
@@ -40,6 +46,13 @@ public class Book {
     private String description;
 
     private String coverImage;
+    @ManyToMany(fetch = FetchType.LAZY)
+    @JoinTable(
+            name = "books_categories",
+            joinColumns = @JoinColumn(name = "book_id"),
+            inverseJoinColumns = @JoinColumn(name = "category_id")
+    )
+    private Set<Category> categories = new HashSet<>();
 
     @Column(nullable = false)
     private boolean isDeleted;

src/main/java/mate/academy/bookstore/model/Category.java

@@ -0,0 +1,25 @@
+package mate.academy.bookstore.model;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.Table;
+import lombok.Getter;
+import lombok.Setter;
+import org.hibernate.annotations.SoftDelete;
+
+@Getter
+@Setter
+@Entity
+@SoftDelete
+@Table(name = "categories")
+public class Category {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+    @Column(nullable = false, unique = true)
+    private String name;
+    private String description;
+}

src/main/java/mate/academy/bookstore/repository/book/BookRepository.java

@@ -1,9 +1,18 @@
 package mate.academy.bookstore.repository.book;
 
+import java.util.List;
 import mate.academy.bookstore.model.Book;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.jpa.repository.EntityGraph;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 
 public interface BookRepository extends JpaRepository<Book, Long>, JpaSpecificationExecutor<Book> {
+    @EntityGraph(attributePaths = {"categories"})
     Book findBookByIsbn(String isbn);
+
+    @Query("SELECT b FROM Book b LEFT JOIN FETCH b.categories c WHERE c.id = :categoryId")
+    List<Book> findAllBooksByCategoryId(@Param("categoryId") Long categoryId, Pageable pageable);
 }

src/main/java/mate/academy/bookstore/repository/category/CategoryRepository.java

@@ -0,0 +1,9 @@
+package mate.academy.bookstore.repository.category;
+
+import mate.academy.bookstore.model.Category;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface CategoryRepository extends JpaRepository<Category, Long> {
+
+    Category findByName(String categoryName);
+}

src/main/java/mate/academy/bookstore/service/BookService.java

@@ -2,20 +2,23 @@
 
 import java.util.List;
 import mate.academy.bookstore.dto.book.BookDto;
-import mate.academy.bookstore.dto.book.BookRequestDto;
+import mate.academy.bookstore.dto.book.BookDtoWithoutCategoryIds;
 import mate.academy.bookstore.dto.book.BookSearchParametersDto;
+import mate.academy.bookstore.dto.book.CreateBookRequestDto;
 import org.springframework.data.domain.Pageable;
 
 public interface BookService {
-    BookDto save(BookRequestDto requestDto);
+    BookDto save(CreateBookRequestDto requestDto);
 
     List<BookDto> findAll(Pageable pageable);
 
     BookDto findById(Long id);
 
     List<BookDto> search(BookSearchParametersDto parametersDto, Pageable pageable);
 
-    BookDto updateById(Long id, BookRequestDto requestDto);
+    BookDto updateById(Long id, CreateBookRequestDto requestDto);
 
     void delete(Long id);
+
+    List<BookDtoWithoutCategoryIds> getAllBookByCategoryId(Long id, Pageable pageable);
 }

src/main/java/mate/academy/bookstore/service/CategoryService.java

@@ -0,0 +1,17 @@
+package mate.academy.bookstore.service;
+
+import java.util.List;
+import mate.academy.bookstore.dto.category.CategoryDto;
+import org.springframework.data.domain.Pageable;
+
+public interface CategoryService {
+    List<CategoryDto> findAll(Pageable pageable);
+
+    CategoryDto getById(Long id);
+
+    CategoryDto save(CategoryDto categoryDto);
+
+    CategoryDto update(Long id, CategoryDto categoryDto);
+
+    void delete(Long id);
+}