Add Readme.md

Readme.md

@@ -0,0 +1,3 @@
+Le projet mylibrary-template 
+
+Groupe : Abed BRIDJA, Wilfried Brigitte, Christopher Dubreuil 

pom.xml

@@ -117,6 +117,20 @@
       <version>${mockito.version}</version>
       <scope>test</scope>
     </dependency>
+      <dependency>
+          <groupId>junit</groupId>
+          <artifactId>junit</artifactId>
+          <version>4.13.2</version>
+          <scope>compile</scope>
+      </dependency>
+      <dependency>
+          <groupId>org.junit.jupiter</groupId>
+          <artifactId>junit-jupiter-api</artifactId>
+      </dependency>
+      <dependency>
+          <groupId>org.junit.jupiter</groupId>
+          <artifactId>junit-jupiter-params</artifactId>
+      </dependency>
   </dependencies>
 
   <build>

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/BookDTO.java

@@ -0,0 +1,25 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book;
+
+import lombok.Builder;
+import lombok.Getter;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.UUID;
+
+@Builder
+@Getter
+public class BookDTO {
+  private final UUID id;
+  private final String isbn;
+  private final String title;
+  private final String author;
+  private final String publisher;
+  private final LocalDate publicationDate;
+  private final BigDecimal price;
+  private final int stock;
+  private final List<String> categories;
+  private final String description;
+  private final String language;
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/BookInfo.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.book;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+
+public record BookInfo(
+    String isbn,
+    String title,
+    String author,
+    String publisher,
+    LocalDate publicationDate,
+    BigDecimal price,
+    int initialStock,
+    List<String> categories,
+    String description,
+    String language
+) {
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/converter/BookConverter.java

@@ -0,0 +1,42 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.converter;
+ 
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.entity.Book;
+ 
+public final class BookConverter {
+ 
+  private BookConverter() {
+  }
+ 
+  public static Book toDomain(BookInfo bookInfo) {
+    return Book.builder()
+        .isbn(bookInfo.isbn())
+        .title(bookInfo.title())
+        .author(bookInfo.author())
+        .publisher(bookInfo.publisher())
+        .publicationDate(bookInfo.publicationDate())
+        .price(bookInfo.price())
+        .stock(bookInfo.initialStock())
+        .categories(bookInfo.categories())
+        .description(bookInfo.description())
+        .language(bookInfo.language())
+        .build();
+  }
+ 
+  public static BookDTO toDTO(Book book) {
+    return BookDTO.builder()
+        .id(book.getId())
+        .isbn(book.getIsbn())
+        .title(book.getTitle())
+        .author(book.getAuthor())
+        .publisher(book.getPublisher())
+        .publicationDate(book.getPublicationDate())
+        .price(book.getPrice())
+        .stock(book.getStock())
+        .categories(book.getCategories())
+        .description(book.getDescription())
+        .language(book.getLanguage())
+        .build();
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/entity/Book.java

@@ -0,0 +1,31 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.entity;
+
+import lombok.Builder;
+import lombok.Getter;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.UUID;
+ 
+@Builder
+@Getter
+public class Book {
+ 
+  private UUID id;
+  private String isbn;
+  private String title;
+  private String author;
+  private String publisher;
+  private LocalDate publicationDate;
+  private BigDecimal price;
+  private int stock;
+  private List<String> categories;
+  private String description;
+  private String language;
+ 
+  public void setRandomUUID() {
+    this.id = UUID.randomUUID();
+  }
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/exception/BookNotFoundException.java

@@ -0,0 +1,14 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.exception;
+ 
+import java.text.MessageFormat;
+import java.util.UUID;
+ 
+public class BookNotFoundException extends Exception {
+ 
+  public static final String THE_BOOK_WITH_ID_DOES_NOT_EXIST_MESSAGE = "The book with id {0} does not exist";
+ 
+  public BookNotFoundException(UUID uuid) {
+    super(MessageFormat.format(THE_BOOK_WITH_ID_DOES_NOT_EXIST_MESSAGE, uuid));
+  }
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/exception/NotValidBookException.java

@@ -0,0 +1,9 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.exception;
+ 
+public class NotValidBookException extends Exception {
+ 
+  public NotValidBookException(String message) {
+    super(message);
+  }
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/repository/BookRepository.java

@@ -0,0 +1,52 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.repository;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.entity.Book;
+import lombok.NoArgsConstructor;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+ 
+@NoArgsConstructor
+public final class BookRepository {
+ 
+  private final List<Book> books = new ArrayList<>();
+ 
+  public List<Book> findAll() {
+    return books;
+  }
+ 
+  public void deleteAll() {
+    books.clear();
+  }
+ 
+  public Book save(Book newBook) {
+    Optional<Book> optionalBookWithSameId = this.findById(newBook.getId());
+    optionalBookWithSameId.ifPresentOrElse(books::remove, newBook::setRandomUUID);
+    this.books.add(newBook);
+    return newBook;
+  }
+ 
+  public Optional<Book> findById(UUID uuid) {
+    return this.books.stream()
+        .filter(book -> book.getId().equals(uuid))
+        .findFirst();
+  }
+ 
+  public boolean existsById(UUID uuid) {
+    return this.books.stream()
+        .anyMatch(book -> book.getId().equals(uuid));
+  }
+ 
+  public Optional<Book> findByIsbn(String isbn) {
+    return this.books.stream()
+        .filter(book -> book.getIsbn().equals(isbn))
+        .findFirst();
+  }
+ 
+  public void delete(Book book) {
+    this.books.remove(book);
+  }
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/usecase/BookUseCase.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.book.usecase;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.converter.BookConverter;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.entity.Book;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.exception.BookNotFoundException;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.exception.NotValidBookException;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.repository.BookRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.validator.BookValidator;
+
+import java.util.Optional;
+import java.util.UUID;
+ 
+public final class BookUseCase {
+ 
+  private final BookRepository bookRepository;
+ 
+  public BookUseCase(BookRepository bookRepository) {
+    this.bookRepository = bookRepository;
+  }
+ 
+  public String registerBook(BookInfo bookInfo) throws NotValidBookException {
+    BookValidator.validate(bookInfo);
+    Book bookToRegister = BookConverter.toDomain(bookInfo);
+    Book registeredBook = bookRepository.save(bookToRegister);
+    return registeredBook.getIsbn();
+  }
+ 
+  public Optional<BookDTO> findBookByIsbn(String isbn) {
+    Optional<Book> optionalBook = bookRepository.findByIsbn(isbn);
+    return optionalBook.map(BookConverter::toDTO);
+  }
+ 
+  public BookDTO updateBook(UUID uuid, BookInfo bookInfo) throws BookNotFoundException, NotValidBookException {
+    BookValidator.validate(bookInfo);
+    Book existingBook = getBookIfNotFoundThrowException(uuid);
+    Book updatedBook = Book.builder()
+        .id(uuid)
+        .isbn(bookInfo.isbn())
+        .title(bookInfo.title())
+        .author(bookInfo.author())
+        .publisher(bookInfo.publisher())
+        .publicationDate(bookInfo.publicationDate())
+        .price(bookInfo.price())
+        .stock(existingBook.getStock())
+        .categories(bookInfo.categories())
+        .description(bookInfo.description())
+        .language(bookInfo.language())
+        .build();
+    Book saved = bookRepository.save(updatedBook);
+    return BookConverter.toDTO(saved);
+  }
+ 
+  public void deleteBook(UUID uuid) throws BookNotFoundException {
+    Book bookToDelete = getBookIfNotFoundThrowException(uuid);
+    bookRepository.delete(bookToDelete);
+  }
+ 
+  private Book getBookIfNotFoundThrowException(UUID uuid) throws BookNotFoundException {
+    Optional<Book> optionalBook = bookRepository.findById(uuid);
+    if (optionalBook.isEmpty()) {
+      throw new BookNotFoundException(uuid);
+    }
+    return optionalBook.get();
+  }
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/book/validator/BookValidator.java

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+package fr.iut_fbleau.but3.dev62.mylibrary.book.validator;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.exception.NotValidBookException;
+
+import java.math.BigDecimal;
+ 
+public final class BookValidator {
+ 
+  public static final String ISBN_IS_NOT_VALID = "ISBN is not valid";
+  public static final String PRICE_MUST_BE_POSITIVE = "Price must be positive";
+  public static final String TITLE_CANNOT_BE_BLANK = "Title cannot be blank";
+  public static final String AUTHOR_CANNOT_BE_BLANK = "Author cannot be blank";
+  public static final String PUBLISHER_CANNOT_BE_BLANK = "Publisher cannot be blank";
+  public static final String ISBN_REGEX = "\\d{13}";
+ 
+  private BookValidator() {
+  }
+ 
+  public static void validate(BookInfo bookInfo) throws NotValidBookException {
+    validateIsbn(bookInfo);
+    validateTitle(bookInfo);
+    validateAuthor(bookInfo);
+    validatePublisher(bookInfo);
+    validatePrice(bookInfo);
+  }
+ 
+  private static void validateIsbn(BookInfo bookInfo) throws NotValidBookException {
+    if (bookInfo.isbn() == null || bookInfo.isbn().isBlank()) {
+      throw new NotValidBookException(ISBN_IS_NOT_VALID);
+    }
+    if (!bookInfo.isbn().matches(ISBN_REGEX)) {
+      throw new NotValidBookException(ISBN_IS_NOT_VALID);
+    }
+  }
+ 
+  private static void validateTitle(BookInfo bookInfo) throws NotValidBookException {
+    if (bookInfo.title() == null || bookInfo.title().isBlank()) {
+      throw new NotValidBookException(TITLE_CANNOT_BE_BLANK);
+    }
+  }
+ 
+  private static void validateAuthor(BookInfo bookInfo) throws NotValidBookException {
+    if (bookInfo.author() == null || bookInfo.author().isBlank()) {
+      throw new NotValidBookException(AUTHOR_CANNOT_BE_BLANK);
+    }
+  }
+ 
+  private static void validatePublisher(BookInfo bookInfo) throws NotValidBookException {
+    if (bookInfo.publisher() == null || bookInfo.publisher().isBlank()) {
+      throw new NotValidBookException(PUBLISHER_CANNOT_BE_BLANK);
+    }
+  }
+ 
+  private static void validatePrice(BookInfo bookInfo) throws NotValidBookException {
+    if (bookInfo.price() == null || bookInfo.price().compareTo(BigDecimal.ZERO) <= 0) {
+      throw new NotValidBookException(PRICE_MUST_BE_POSITIVE);
+    }
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/AdresseLivraison.java

@@ -0,0 +1,5 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order;
+ 
+public record AdresseLivraison(String rue, String ville, String codePostal, String pays) {
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/LigneCommandeInfo.java

@@ -0,0 +1,7 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order;
+ 
+import java.util.UUID;
+ 
+public record LigneCommandeInfo(UUID livreId, int quantite) {
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/ModePaiement.java

@@ -0,0 +1,8 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order;
+ 
+public enum ModePaiement {
+  CB,
+  PAYPAL,
+  POINTS_FIDELITE
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/OrderDTO.java

@@ -0,0 +1,16 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order;
+
+import lombok.Builder;
+import lombok.Getter;
+
+import java.math.BigDecimal;
+import java.util.UUID;
+ 
+@Builder
+@Getter
+public class OrderDTO {
+  private final UUID commandeId;
+  private final BigDecimal montantTotal;
+  private final int pointsFideliteGagnes;
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/OrderInfo.java

@@ -0,0 +1,13 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order;
+ 
+import java.util.List;
+import java.util.UUID;
+ 
+public record OrderInfo(
+    UUID clientId,
+    List<LigneCommandeInfo> lignesCommande,
+    AdresseLivraison adresseLivraison,
+    ModePaiement modePaiement
+) {
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/converter/OrderConverter.java

@@ -0,0 +1,35 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.converter;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.order.OrderDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.OrderInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.LigneCommande;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.Order;
+
+import java.math.BigDecimal;
+import java.util.List;
+ 
+public final class OrderConverter {
+ 
+  private OrderConverter() {
+  }
+ 
+  public static Order toDomain(OrderInfo orderInfo, List<LigneCommande> lignes,
+      BigDecimal montantTotal, int pointsFideliteGagnes) {
+    return Order.builder()
+        .clientId(orderInfo.clientId())
+        .lignesCommande(lignes)
+        .adresseLivraison(orderInfo.adresseLivraison())
+        .modePaiement(orderInfo.modePaiement())
+        .montantTotal(montantTotal)
+        .pointsFideliteGagnes(pointsFideliteGagnes)
+        .build();
+  }
+ 
+  public static OrderDTO toDTO(Order order) {
+    return OrderDTO.builder()
+        .commandeId(order.getId())
+        .montantTotal(order.getMontantTotal())
+        .pointsFideliteGagnes(order.getPointsFideliteGagnes())
+        .build();
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/entity/LigneCommande.java

@@ -0,0 +1,16 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.entity;
+
+import lombok.Builder;
+import lombok.Getter;
+
+import java.math.BigDecimal;
+import java.util.UUID;
+ 
+@Builder
+@Getter
+public class LigneCommande {
+  private UUID livreId;
+  private int quantite;
+  private BigDecimal prixUnitaire;
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/entity/Order.java

@@ -0,0 +1,27 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.entity;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.order.AdresseLivraison;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.ModePaiement;
+import lombok.Builder;
+import lombok.Getter;
+
+import java.math.BigDecimal;
+import java.util.List;
+import java.util.UUID;
+ 
+@Builder
+@Getter
+public class Order {
+  private UUID id;
+  private UUID clientId;
+  private List<LigneCommande> lignesCommande;
+  private AdresseLivraison adresseLivraison;
+  private ModePaiement modePaiement;
+  private BigDecimal montantTotal;
+  private int pointsFideliteGagnes;
+ 
+  public void setRandomUUID() {
+    this.id = UUID.randomUUID();
+  }
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/exception/NotValidOrderException.java

@@ -0,0 +1,9 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.exception;
+ 
+public class NotValidOrderException extends Exception {
+ 
+  public NotValidOrderException(String message) {
+    super(message);
+  }
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/exception/OrderNotFoundException.java

@@ -0,0 +1,14 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.exception;
+ 
+import java.text.MessageFormat;
+import java.util.UUID;
+ 
+public class OrderNotFoundException extends Exception {
+ 
+  public static final String THE_ORDER_WITH_ID_DOES_NOT_EXIST_MESSAGE = "The order with id {0} does not exist";
+ 
+  public OrderNotFoundException(UUID uuid) {
+    super(MessageFormat.format(THE_ORDER_WITH_ID_DOES_NOT_EXIST_MESSAGE, uuid));
+  }
+}
+ 

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/repository/OrderRepository.java

@@ -0,0 +1,51 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.repository;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.Order;
+import lombok.NoArgsConstructor;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+ 
+@NoArgsConstructor
+public final class OrderRepository {
+ 
+  private final List<Order> orders = new ArrayList<>();
+ 
+  public List<Order> findAll() {
+    return orders;
+  }
+ 
+  public void deleteAll() {
+    orders.clear();
+  }
+ 
+  public Order save(Order newOrder) {
+    Optional<Order> existing = this.findById(newOrder.getId());
+    existing.ifPresentOrElse(orders::remove, newOrder::setRandomUUID);
+    this.orders.add(newOrder);
+    return newOrder;
+  }
+ 
+  public Optional<Order> findById(UUID uuid) {
+    return this.orders.stream()
+        .filter(order -> order.getId().equals(uuid))
+        .findFirst();
+  }
+ 
+  public boolean existsById(UUID uuid) {
+    return this.orders.stream()
+        .anyMatch(order -> order.getId().equals(uuid));
+  }
+ 
+  public List<Order> findByClientId(UUID clientId) {
+    return this.orders.stream()
+        .filter(order -> order.getClientId().equals(clientId))
+        .toList();
+  }
+ 
+  public void delete(Order order) {
+    this.orders.remove(order);
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/usecase/OrderUseCase.java

@@ -0,0 +1,80 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.usecase;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.entity.Book;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.repository.BookRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.CustomerNotFoundException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.repository.CustomerRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.LigneCommandeInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.ModePaiement;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.OrderDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.OrderInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.converter.OrderConverter;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.LigneCommande;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.Order;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.exception.NotValidOrderException;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.repository.OrderRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.validator.OrderValidator;
+
+import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+ 
+public final class OrderUseCase {
+ 
+  private final OrderRepository orderRepository;
+  private final CustomerRepository customerRepository;
+  private final BookRepository bookRepository;
+ 
+  public OrderUseCase(OrderRepository orderRepository, CustomerRepository customerRepository,
+      BookRepository bookRepository) {
+    this.orderRepository = orderRepository;
+    this.customerRepository = customerRepository;
+    this.bookRepository = bookRepository;
+  }
+ 
+  public OrderDTO passerCommande(OrderInfo orderInfo)
+      throws NotValidOrderException, CustomerNotFoundException {
+    OrderValidator.validate(orderInfo);
+ 
+    Customer customer = customerRepository.findById(orderInfo.clientId())
+        .orElseThrow(() -> new CustomerNotFoundException(orderInfo.clientId()));
+ 
+    List<LigneCommande> lignes = new ArrayList<>();
+    BigDecimal montantTotal = BigDecimal.ZERO;
+ 
+    for (LigneCommandeInfo ligneInfo : orderInfo.lignesCommande()) {
+      Book book = bookRepository.findById(ligneInfo.livreId())
+          .orElseThrow(() -> new NotValidOrderException("Book not found: " + ligneInfo.livreId()));
+ 
+      BigDecimal prixLigne = book.getPrice().multiply(BigDecimal.valueOf(ligneInfo.quantite()));
+      montantTotal = montantTotal.add(prixLigne);
+ 
+      lignes.add(LigneCommande.builder()
+          .livreId(ligneInfo.livreId())
+          .quantite(ligneInfo.quantite())
+          .prixUnitaire(book.getPrice())
+          .build());
+    }
+ 
+    int pointsGagnes = montantTotal.intValue();
+ 
+    if (orderInfo.modePaiement() == ModePaiement.POINTS_FIDELITE) {
+      customer.addLoyaltyPoints(-montantTotal.intValue());
+    } else {
+      customer.addLoyaltyPoints(pointsGagnes);
+    }
+    customerRepository.save(customer);
+ 
+    Order order = OrderConverter.toDomain(orderInfo, lignes, montantTotal, pointsGagnes);
+    Order savedOrder = orderRepository.save(order);
+ 
+    return OrderConverter.toDTO(savedOrder);
+  }
+ 
+  public Optional<OrderDTO> findOrderById(UUID uuid) {
+    return orderRepository.findById(uuid).map(OrderConverter::toDTO);
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/order/validator/OrderValidator.java

@@ -0,0 +1,53 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.validator;
+ 
+import fr.iut_fbleau.but3.dev62.mylibrary.order.LigneCommandeInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.OrderInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.exception.NotValidOrderException;
+ 
+public final class OrderValidator {
+ 
+  public static final String CLIENT_ID_CANNOT_BE_NULL = "Client id cannot be null";
+  public static final String LIGNES_COMMANDE_CANNOT_BE_EMPTY = "Order must have at least one item";
+  public static final String QUANTITE_MUST_BE_POSITIVE = "Quantity must be positive";
+  public static final String MODE_PAIEMENT_CANNOT_BE_NULL = "Payment method cannot be null";
+  public static final String ADRESSE_LIVRAISON_CANNOT_BE_NULL = "Delivery address cannot be null";
+ 
+  private OrderValidator() {
+  }
+ 
+  public static void validate(OrderInfo orderInfo) throws NotValidOrderException {
+    validateClientId(orderInfo);
+    validateLignesCommande(orderInfo);
+    validateAdresseLivraison(orderInfo);
+    validateModePaiement(orderInfo);
+  }
+ 
+  private static void validateClientId(OrderInfo orderInfo) throws NotValidOrderException {
+    if (orderInfo.clientId() == null) {
+      throw new NotValidOrderException(CLIENT_ID_CANNOT_BE_NULL);
+    }
+  }
+ 
+  private static void validateLignesCommande(OrderInfo orderInfo) throws NotValidOrderException {
+    if (orderInfo.lignesCommande() == null || orderInfo.lignesCommande().isEmpty()) {
+      throw new NotValidOrderException(LIGNES_COMMANDE_CANNOT_BE_EMPTY);
+    }
+    for (LigneCommandeInfo ligne : orderInfo.lignesCommande()) {
+      if (ligne.quantite() <= 0) {
+        throw new NotValidOrderException(QUANTITE_MUST_BE_POSITIVE);
+      }
+    }
+  }
+ 
+  private static void validateAdresseLivraison(OrderInfo orderInfo) throws NotValidOrderException {
+    if (orderInfo.adresseLivraison() == null) {
+      throw new NotValidOrderException(ADRESSE_LIVRAISON_CANNOT_BE_NULL);
+    }
+  }
+ 
+  private static void validateModePaiement(OrderInfo orderInfo) throws NotValidOrderException {
+    if (orderInfo.modePaiement() == null) {
+      throw new NotValidOrderException(MODE_PAIEMENT_CANNOT_BE_NULL);
+    }
+  }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/ModePaiement.java

@@ -0,0 +1,13 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription;
+
+
+import lombok.Builder;
+import lombok.Getter;
+
+@Getter
+@Builder
+public class ModePaiement {
+    private final TypePaiement type;
+    private final Object details;
+
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/SubscriptionDTO.java

@@ -0,0 +1,17 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription;
+
+import lombok.Builder;
+import lombok.Getter;
+
+import java.math.BigDecimal;
+import java.util.Date;
+import java.util.UUID;
+
+@Builder
+@Getter
+public class SubscriptionDTO {
+    private final UUID abonnementId;
+    private final Date dateDebut;
+    private final Date dateFin;
+    private final BigDecimal montantMensuel;
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/SubscriptionDuree.java

@@ -0,0 +1,21 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription;
+
+import java.math.BigDecimal;
+
+public enum SubscriptionDuree {
+    M3,M6,M12;
+
+    private Integer[] subValues = {3,6,12};
+    private BigDecimal[] subPrices = {BigDecimal.valueOf(9.99), BigDecimal.valueOf(9.50),
+            BigDecimal.valueOf(8.99)};
+
+    public int getValue(){
+        return subValues[this.ordinal()];
+    }
+
+    public BigDecimal getMonthlyPricing(){
+        return subPrices[this.ordinal()];
+    }
+
+
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/SubscriptionInfo.java

@@ -0,0 +1,12 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription;
+
+import java.util.Date;
+import java.util.UUID;
+
+public record SubscriptionInfo (
+        UUID clientId,
+        SubscriptionDuree duree,
+        ModePaiement modePaiement,
+        Date dateDebutSouhaitee
+) {
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/TypePaiement.java

@@ -0,0 +1,6 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription;
+
+public enum TypePaiement {
+    CB,
+    Paypal
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/converter/SubscriptionConverter.java

@@ -0,0 +1,39 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription.converter;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.SubscriptionDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.SubscriptionInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.entity.Subscription;
+
+import java.util.Calendar;
+
+public final class SubscriptionConverter {
+
+    private SubscriptionConverter() {
+    }
+
+    public static Subscription toDomain(SubscriptionInfo subscriptionInfo) {
+        Subscription sub = Subscription.builder()
+                .clientId(subscriptionInfo.clientId())
+                .duree(subscriptionInfo.duree())
+                .modePaiement(subscriptionInfo.modePaiement())
+                .dateDebutSouhaitee(subscriptionInfo.dateDebutSouhaitee())
+                .build();
+        sub.setRandomUUID();
+        return sub;
+    }
+
+    public static SubscriptionDTO toDTO(Subscription subscription) {
+
+        Calendar cal = Calendar.getInstance();
+        cal.setTime(subscription.getDateDebutSouhaitee());
+        cal.add(Calendar.MONTH, subscription.getDuree().getValue());
+
+        return SubscriptionDTO.builder()
+                .abonnementId(subscription.getAbonnementId())
+                .dateDebut(subscription.getDateDebutSouhaitee())
+                .dateFin(cal.getTime())
+                .montantMensuel(subscription.getDuree().getMonthlyPricing())
+                .build();
+
+    }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/entity/Subscription.java

@@ -0,0 +1,25 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription.entity;
+
+
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.ModePaiement;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.SubscriptionDuree;
+import lombok.Builder;
+import lombok.Getter;
+
+import java.util.Date;
+import java.util.UUID;
+
+@Builder
+@Getter
+public class Subscription {
+    private UUID abonnementId;
+    private UUID clientId;
+    private SubscriptionDuree duree;
+    private ModePaiement modePaiement;
+    private Date dateDebutSouhaitee;
+
+    public void setRandomUUID() {
+        this.abonnementId = UUID.randomUUID();
+    }
+
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/exception/NotValidSubscriptionException.java

@@ -0,0 +1,8 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription.exception;
+
+public class NotValidSubscriptionException extends Exception {
+
+    public NotValidSubscriptionException(String message) {
+        super(message);
+    }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/exception/SubscriptionNotFoundException.java

@@ -0,0 +1,12 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription.exception;
+
+import java.text.MessageFormat;
+import java.util.UUID;
+
+public class SubscriptionNotFoundException extends Exception{
+    public static final String THE_SUBSCRIPTION_WITH_ID_DOES_NOT_EXIST_MESSAGE = "The Subscription with id {0} does not exist";
+
+    public SubscriptionNotFoundException(UUID uuid) {
+        super(MessageFormat.format(THE_SUBSCRIPTION_WITH_ID_DOES_NOT_EXIST_MESSAGE, uuid));
+    }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/repository/SubscriptionRepository.java

@@ -0,0 +1,51 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription.repository;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.entity.Subscription;
+import lombok.NoArgsConstructor;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+
+@NoArgsConstructor
+public final class SubscriptionRepository {
+
+    private final List<Subscription> subscriptions = new ArrayList<>();
+
+    public List<Subscription> findAll() {
+        return subscriptions;
+    }
+
+    public void deleteAll() {
+        subscriptions.clear();
+    }
+
+    public Subscription save(Subscription newSubscription) {
+        Optional<Subscription> optionalBookWithSameId = this.findByUuid(newSubscription.getAbonnementId());
+        optionalBookWithSameId.ifPresentOrElse(subscriptions::remove, newSubscription::setRandomUUID);
+        this.subscriptions.add(newSubscription);
+        return newSubscription;
+    }
+
+    public Optional<Subscription> findByUuid(UUID uuid) {
+        return this.subscriptions.stream()
+                .filter(subscription -> subscription.getAbonnementId().equals(uuid))
+                .findFirst();
+    }
+
+    public boolean existsById(UUID uuid) {
+        return this.subscriptions.stream()
+                .anyMatch(subscription -> subscription.getAbonnementId().equals(uuid));
+    }
+
+    public Optional<Subscription> findByClientUuid(UUID uuid) {
+        return this.subscriptions.stream()
+                .filter(subscription -> subscription.getClientId().equals(uuid))
+                .findFirst();
+    }
+
+    public void delete(Subscription subscription) {
+        this.subscriptions.remove(subscription);
+    }
+}

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/usecase/SubscriptionUseCase.java

@@ -0,0 +1,63 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription.usecase;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.SubscriptionDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.SubscriptionInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.converter.SubscriptionConverter;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.entity.Subscription;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.exception.NotValidSubscriptionException;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.exception.SubscriptionNotFoundException;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.repository.SubscriptionRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.validator.SubscriptionValidator;
+
+import java.util.Optional;
+import java.util.UUID;
+
+public class SubscriptionUseCase {
+
+    private final SubscriptionRepository subscriptionRepository;
+
+    public SubscriptionUseCase(SubscriptionRepository subscriptionRepository) {
+        this.subscriptionRepository = subscriptionRepository;
+
+    }
+
+    public SubscriptionDTO registerSubscription(SubscriptionInfo subscriptionInfo) throws NotValidSubscriptionException {
+        SubscriptionValidator.validate(subscriptionInfo);
+        Subscription subscriptionToRegister = SubscriptionConverter.toDomain(subscriptionInfo);
+        Subscription registeredSubscription = subscriptionRepository.save(subscriptionToRegister);
+        return SubscriptionConverter.toDTO(registeredSubscription);
+    }
+
+    public Optional<SubscriptionDTO> findSubscriptionByUuid(UUID uuid) {
+        Optional<Subscription> optionalSubscription = subscriptionRepository.findByClientUuid(uuid);
+        return optionalSubscription.map(SubscriptionConverter::toDTO);
+    }
+
+    public SubscriptionDTO updateSubscription(UUID uuid, SubscriptionInfo subscriptionInfo) throws SubscriptionNotFoundException, NotValidSubscriptionException {
+        SubscriptionValidator.validate(subscriptionInfo);
+        Subscription existingSubscription = getSubscriptionIfNotFoundThrowException(uuid);
+        Subscription updatedSubscription = Subscription.builder()
+                .abonnementId(uuid)
+                .clientId(subscriptionInfo.clientId())
+                .duree(subscriptionInfo.duree())
+                .modePaiement(subscriptionInfo.modePaiement())
+                .dateDebutSouhaitee(subscriptionInfo.dateDebutSouhaitee())
+                .build();
+        Subscription saved = subscriptionRepository.save(updatedSubscription);
+        return SubscriptionConverter.toDTO(saved);
+    }
+
+    public void deleteSubscription(UUID uuid) throws SubscriptionNotFoundException {
+        Subscription subscriptionToDelete = getSubscriptionIfNotFoundThrowException(uuid);
+        subscriptionRepository.delete(subscriptionToDelete);
+    }
+
+    private Subscription getSubscriptionIfNotFoundThrowException(UUID uuid) throws SubscriptionNotFoundException {
+        Optional<Subscription> optionalSubscription = subscriptionRepository.findByUuid(uuid);
+        if (optionalSubscription.isEmpty()) {
+            throw new SubscriptionNotFoundException(uuid);
+        }
+        return optionalSubscription.get();
+    }
+}
+

src/main/java/fr/iut_fbleau/but3/dev62/mylibrary/subscription/validator/SubscriptionValidator.java

@@ -0,0 +1,51 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.subscription.validator;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.SubscriptionInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.TypePaiement;
+import fr.iut_fbleau.but3.dev62.mylibrary.subscription.exception.NotValidSubscriptionException;
+
+public final class SubscriptionValidator {
+
+    public static final String Client_ID_NOT_VALID = "l'identifient du client est incorect" ;
+    public static final String LA_DUREE_RENSEIGNEE_N_EST_PAS_CORRECTE = "La durée renseignée n'est pas correcte";
+    public static final String LE_TYPE_DE_PAYEMENT_N_EST_PAS_PRIS_EN_CHARGE = "Le type de payement n'est pas pris en charge";
+    public static final String LA_DATE_DE_DEBUT_N_A_PAS_ETE_RENSEIGNEE = "La date de début n'a pas été renseignée";
+
+    private SubscriptionValidator() {
+    }
+
+    public static void validate(SubscriptionInfo bookInfo) throws NotValidSubscriptionException {
+        validateClientID(bookInfo);
+        validateDuree(bookInfo);
+        validateModePaiement(bookInfo);
+        validateDateDebut(bookInfo);
+    }
+
+    private static void validateClientID(SubscriptionInfo bookInfo) throws NotValidSubscriptionException {
+        if (bookInfo.clientId() == null){
+            throw new NotValidSubscriptionException(Client_ID_NOT_VALID);
+        }
+    }
+
+    private static void validateDuree(SubscriptionInfo bookInfo) throws NotValidSubscriptionException {
+        try {
+            if (bookInfo.duree().getValue() != 3 && bookInfo.duree().getValue() != 6 && bookInfo.duree().getValue() != 12){
+                throw new NotValidSubscriptionException(LA_DUREE_RENSEIGNEE_N_EST_PAS_CORRECTE);
+            }
+        } catch (Exception e) {
+            throw new NotValidSubscriptionException(LA_DUREE_RENSEIGNEE_N_EST_PAS_CORRECTE);
+        }
+    }
+
+    private static void validateModePaiement(SubscriptionInfo bookInfo) throws NotValidSubscriptionException{
+        if (bookInfo.modePaiement().getType() != TypePaiement.CB && bookInfo.modePaiement().getType() != TypePaiement.Paypal){
+            throw new NotValidSubscriptionException(LE_TYPE_DE_PAYEMENT_N_EST_PAS_PRIS_EN_CHARGE);
+        }
+    }
+
+    private static void validateDateDebut(SubscriptionInfo bookInfo) throws NotValidSubscriptionException{
+        if (bookInfo.dateDebutSouhaitee() == null){
+            throw new NotValidSubscriptionException(LA_DATE_DE_DEBUT_N_A_PAS_ETE_RENSEIGNEE);
+        }
+    }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/avis/converter/AvisConverterTest.java

@@ -10,6 +10,7 @@ import org.junit.jupiter.api.Test;
 import java.time.LocalDate;
 import java.util.UUID;
 
+
 import static org.junit.jupiter.api.Assertions.*;
 
 @DisplayName("AvisConverter Unit Tests")

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/book/converter/BookConverterTest.java

@@ -0,0 +1,108 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.converter;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.entity.Book;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@DisplayName("BookConverter Unit Tests")
+class BookConverterTest {
+
+  @Nested
+  @DisplayName("toDomain() method tests")
+  class ToDomainTests {
+
+    @Test
+    @DisplayName("Should convert BookInfo to Book domain object")
+    void shouldConvertBookInfoToDomain() {
+      BookInfo bookInfo = new BookInfo(
+          "9782016289308",
+          "Le Petit Prince",
+          "Antoine de Saint-Exupéry",
+          "Gallimard",
+          LocalDate.of(1943, 4, 6),
+          new BigDecimal("12.90"),
+          10,
+          List.of("Roman", "Jeunesse"),
+          "Un classique",
+          "FR"
+      );
+
+      Book result = BookConverter.toDomain(bookInfo);
+
+      assertNotNull(result);
+      assertEquals(bookInfo.isbn(), result.getIsbn());
+      assertEquals(bookInfo.title(), result.getTitle());
+      assertEquals(bookInfo.author(), result.getAuthor());
+      assertEquals(bookInfo.publisher(), result.getPublisher());
+      assertEquals(bookInfo.publicationDate(), result.getPublicationDate());
+      assertEquals(bookInfo.price(), result.getPrice());
+      assertEquals(bookInfo.initialStock(), result.getStock());
+      assertEquals(bookInfo.categories(), result.getCategories());
+      assertEquals(bookInfo.description(), result.getDescription());
+      assertEquals(bookInfo.language(), result.getLanguage());
+    }
+
+    @Test
+    @DisplayName("Should have null ID after toDomain (set by repository)")
+    void shouldHaveNullIdAfterToDomain() {
+      BookInfo bookInfo = new BookInfo(
+          "9782016289308", "Titre", "Auteur", "Editeur",
+          LocalDate.now(), new BigDecimal("10.00"), 5,
+          List.of("Roman"), "Description", "FR"
+      );
+
+      Book result = BookConverter.toDomain(bookInfo);
+
+      assertNull(result.getId());
+    }
+  }
+
+  @Nested
+  @DisplayName("toDTO() method tests")
+  class ToDTOTests {
+
+    @Test
+    @DisplayName("Should convert Book domain object to BookDTO with all fields mapped correctly")
+    void shouldConvertBookToDTO() {
+      UUID id = UUID.randomUUID();
+      Book book = Book.builder()
+          .id(id)
+          .isbn("9782016289308")
+          .title("Le Petit Prince")
+          .author("Antoine de Saint-Exupéry")
+          .publisher("Gallimard")
+          .publicationDate(LocalDate.of(1943, 4, 6))
+          .price(new BigDecimal("12.90"))
+          .stock(10)
+          .categories(List.of("Roman", "Jeunesse"))
+          .description("Un classique")
+          .language("FR")
+          .build();
+
+      BookDTO result = BookConverter.toDTO(book);
+
+      assertNotNull(result);
+      assertEquals(book.getId(), result.getId());
+      assertEquals(book.getIsbn(), result.getIsbn());
+      assertEquals(book.getTitle(), result.getTitle());
+      assertEquals(book.getAuthor(), result.getAuthor());
+      assertEquals(book.getPublisher(), result.getPublisher());
+      assertEquals(book.getPublicationDate(), result.getPublicationDate());
+      assertEquals(book.getPrice(), result.getPrice());
+      assertEquals(book.getStock(), result.getStock());
+      assertEquals(book.getCategories(), result.getCategories());
+      assertEquals(book.getDescription(), result.getDescription());
+      assertEquals(book.getLanguage(), result.getLanguage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/book/entity/BookTest.java

@@ -0,0 +1,71 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.entity;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class BookTest {
+
+  @Test
+  @DisplayName("Builder should create a valid Book instance")
+  void testBookBuilder() {
+    UUID id = UUID.randomUUID();
+
+    Book book = Book.builder()
+        .id(id)
+        .isbn("9782016289308")
+        .title("Le Petit Prince")
+        .author("Antoine de Saint-Exupéry")
+        .publisher("Gallimard")
+        .publicationDate(LocalDate.of(1943, 4, 6))
+        .price(new BigDecimal("12.90"))
+        .stock(10)
+        .categories(List.of("Roman", "Jeunesse"))
+        .description("Un classique")
+        .language("FR")
+        .build();
+
+    assertEquals(id, book.getId());
+    assertEquals("9782016289308", book.getIsbn());
+    assertEquals("Le Petit Prince", book.getTitle());
+    assertEquals("Antoine de Saint-Exupéry", book.getAuthor());
+    assertEquals("Gallimard", book.getPublisher());
+    assertEquals(LocalDate.of(1943, 4, 6), book.getPublicationDate());
+    assertEquals(new BigDecimal("12.90"), book.getPrice());
+    assertEquals(10, book.getStock());
+    assertEquals(List.of("Roman", "Jeunesse"), book.getCategories());
+    assertEquals("Un classique", book.getDescription());
+    assertEquals("FR", book.getLanguage());
+  }
+
+  @Test
+  @DisplayName("setRandomUUID should set a new non-null UUID")
+  void testSetRandomUUID() {
+    Book book = Book.builder().build();
+    UUID originalId = book.getId();
+
+    book.setRandomUUID();
+
+    assertNotNull(book.getId());
+    assertNotEquals(originalId, book.getId());
+  }
+
+  @Test
+  @DisplayName("Two setRandomUUID calls should produce different UUIDs")
+  void testSetRandomUUIDTwice() {
+    Book book = Book.builder().build();
+    book.setRandomUUID();
+    UUID firstId = book.getId();
+
+    book.setRandomUUID();
+    UUID secondId = book.getId();
+
+    assertNotEquals(firstId, secondId);
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/book/exception/BookNotFoundExceptionTest.java

@@ -0,0 +1,48 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.exception;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class BookNotFoundExceptionTest {
+
+  @Test
+  @DisplayName("Exception message should contain the UUID provided")
+  void testExceptionMessageContainsUUID() {
+    UUID uuid = UUID.randomUUID();
+
+    BookNotFoundException exception = new BookNotFoundException(uuid);
+
+    String expectedMessage = String.format("The book with id %s does not exist", uuid);
+    assertEquals(expectedMessage, exception.getMessage());
+  }
+
+  @Test
+  @DisplayName("Exception should use the correct constant message format")
+  void testExceptionUsesConstantMessageFormat() {
+    UUID uuid = UUID.randomUUID();
+
+    BookNotFoundException exception = new BookNotFoundException(uuid);
+
+    assertEquals("The book with id {0} does not exist",
+        BookNotFoundException.THE_BOOK_WITH_ID_DOES_NOT_EXIST_MESSAGE);
+    assertTrue(exception.getMessage().contains(uuid.toString()));
+  }
+
+  @Test
+  @DisplayName("Exception should be properly thrown and caught")
+  void testExceptionCanBeThrownAndCaught() {
+    UUID uuid = UUID.randomUUID();
+
+    try {
+      throw new BookNotFoundException(uuid);
+    } catch (BookNotFoundException e) {
+      String expectedMessage = String.format("The book with id %s does not exist", uuid);
+      assertEquals(expectedMessage, e.getMessage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/book/exception/NotValidBookExceptionTest.java

@@ -0,0 +1,62 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.exception;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class NotValidBookExceptionTest {
+
+  @Test
+  @DisplayName("Exception should be created with the provided message")
+  void testExceptionCreation() {
+    String errorMessage = "Book data is not valid";
+
+    NotValidBookException exception = new NotValidBookException(errorMessage);
+
+    assertEquals(errorMessage, exception.getMessage());
+  }
+
+  @ParameterizedTest
+  @ValueSource(strings = {
+      "ISBN is not valid",
+      "Title cannot be blank",
+      "Author cannot be blank",
+      "Publisher cannot be blank",
+      "Price must be positive"
+  })
+  @DisplayName("Exception should handle different validation messages")
+  void testExceptionWithDifferentMessages(String errorMessage) {
+    NotValidBookException exception = new NotValidBookException(errorMessage);
+
+    assertEquals(errorMessage, exception.getMessage());
+  }
+
+  @Test
+  @DisplayName("Exception should be properly thrown and caught")
+  void testExceptionCanBeThrownAndCaught() {
+    String errorMessage = "ISBN is not valid";
+
+    Exception exception = assertThrows(NotValidBookException.class, () -> {
+      throw new NotValidBookException(errorMessage);
+    });
+
+    assertEquals(errorMessage, exception.getMessage());
+  }
+
+  @Test
+  @DisplayName("Exception should be catchable as a general Exception")
+  void testExceptionInheritance() {
+    String errorMessage = "Price must be positive";
+
+    try {
+      throw new NotValidBookException(errorMessage);
+    } catch (Exception e) {
+      assertEquals(NotValidBookException.class, e.getClass());
+      assertEquals(errorMessage, e.getMessage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/book/repository/BookRepositoryTest.java

@@ -0,0 +1,219 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.repository;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.entity.Book;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class BookRepositoryTest {
+
+  private BookRepository repository;
+  private Book book1;
+  private Book book2;
+
+  @BeforeEach
+  void setUp() {
+    repository = new BookRepository();
+
+    book1 = Book.builder()
+        .isbn("9782016289308")
+        .title("Le Petit Prince")
+        .author("Antoine de Saint-Exupéry")
+        .publisher("Gallimard")
+        .publicationDate(LocalDate.of(1943, 4, 6))
+        .price(new BigDecimal("12.90"))
+        .stock(10)
+        .categories(List.of("Roman"))
+        .description("Un classique")
+        .language("FR")
+        .build();
+    book1.setRandomUUID();
+
+    book2 = Book.builder()
+        .isbn("9782070409189")
+        .title("L'Étranger")
+        .author("Albert Camus")
+        .publisher("Gallimard")
+        .publicationDate(LocalDate.of(1942, 5, 19))
+        .price(new BigDecimal("9.50"))
+        .stock(5)
+        .categories(List.of("Roman"))
+        .description("Roman philosophique")
+        .language("FR")
+        .build();
+    book2.setRandomUUID();
+  }
+
+  @Test
+  @DisplayName("New repository should be empty")
+  void testNewRepositoryIsEmpty() {
+    assertTrue(repository.findAll().isEmpty());
+    assertEquals(0, repository.findAll().size());
+  }
+
+  @Nested
+  @DisplayName("Save operations")
+  class SaveOperations {
+
+    @Test
+    @DisplayName("Save should add a new book")
+    void testSaveNewBook() {
+      Book saved = repository.save(book1);
+
+      assertEquals(1, repository.findAll().size());
+      assertEquals(book1.getId(), saved.getId());
+      assertEquals(book1.getIsbn(), saved.getIsbn());
+    }
+
+    @Test
+    @DisplayName("Save should update existing book with same ID")
+    void testSaveUpdatesExistingBook() {
+      repository.save(book1);
+      UUID id = book1.getId();
+
+      Book updatedBook = Book.builder()
+          .id(id)
+          .isbn("9782016289308")
+          .title("Le Petit Prince - Edition collector")
+          .author("Antoine de Saint-Exupéry")
+          .publisher("Gallimard")
+          .publicationDate(LocalDate.of(1943, 4, 6))
+          .price(new BigDecimal("19.90"))
+          .stock(3)
+          .categories(List.of("Roman"))
+          .description("Edition collector")
+          .language("FR")
+          .build();
+
+      Book saved = repository.save(updatedBook);
+
+      assertEquals(1, repository.findAll().size());
+      assertEquals(id, saved.getId());
+      assertEquals("Le Petit Prince - Edition collector", saved.getTitle());
+      assertEquals(new BigDecimal("19.90"), saved.getPrice());
+    }
+
+    @Test
+    @DisplayName("Save multiple books should add all of them")
+    void testSaveMultipleBooks() {
+      repository.save(book1);
+      repository.save(book2);
+
+      assertEquals(2, repository.findAll().size());
+      assertTrue(repository.findAll().contains(book1));
+      assertTrue(repository.findAll().contains(book2));
+    }
+  }
+
+  @Nested
+  @DisplayName("Find operations")
+  class FindOperations {
+
+    @BeforeEach
+    void setUpBooks() {
+      repository.save(book1);
+      repository.save(book2);
+    }
+
+    @Test
+    @DisplayName("FindAll should return all books")
+    void testFindAll() {
+      assertEquals(2, repository.findAll().size());
+    }
+
+    @Test
+    @DisplayName("FindById should return book with matching ID")
+    void testFindById() {
+      Optional<Book> found = repository.findById(book1.getId());
+
+      assertTrue(found.isPresent());
+      assertEquals(book1.getIsbn(), found.get().getIsbn());
+      assertEquals(book1.getTitle(), found.get().getTitle());
+    }
+
+    @Test
+    @DisplayName("FindById should return empty Optional when ID doesn't exist")
+    void testFindByIdNotFound() {
+      Optional<Book> found = repository.findById(UUID.randomUUID());
+
+      assertTrue(found.isEmpty());
+    }
+
+    @Test
+    @DisplayName("FindByIsbn should return book with matching ISBN")
+    void testFindByIsbn() {
+      Optional<Book> found = repository.findByIsbn("9782016289308");
+
+      assertTrue(found.isPresent());
+      assertEquals(book1.getId(), found.get().getId());
+    }
+
+    @Test
+    @DisplayName("FindByIsbn should return empty Optional when ISBN doesn't exist")
+    void testFindByIsbnNotFound() {
+      Optional<Book> found = repository.findByIsbn("0000000000000");
+
+      assertTrue(found.isEmpty());
+    }
+
+    @Test
+    @DisplayName("ExistsById should return true when ID exists")
+    void testExistsByIdExists() {
+      assertTrue(repository.existsById(book1.getId()));
+    }
+
+    @Test
+    @DisplayName("ExistsById should return false when ID doesn't exist")
+    void testExistsByIdNotExists() {
+      assertFalse(repository.existsById(UUID.randomUUID()));
+    }
+  }
+
+  @Nested
+  @DisplayName("Delete operations")
+  class DeleteOperations {
+
+    @BeforeEach
+    void setUpBooks() {
+      repository.save(book1);
+      repository.save(book2);
+    }
+
+    @Test
+    @DisplayName("Delete should remove the specified book")
+    void testDelete() {
+      repository.delete(book1);
+
+      assertEquals(1, repository.findAll().size());
+      assertFalse(repository.findAll().contains(book1));
+      assertTrue(repository.findAll().contains(book2));
+    }
+
+    @Test
+    @DisplayName("DeleteAll should remove all books")
+    void testDeleteAll() {
+      repository.deleteAll();
+
+      assertTrue(repository.findAll().isEmpty());
+    }
+
+    @Test
+    @DisplayName("Delete should not throw exception when book doesn't exist")
+    void testDeleteNonExistentBook() {
+      Book nonExistent = Book.builder().isbn("0000000000000").build();
+      nonExistent.setRandomUUID();
+
+      assertDoesNotThrow(() -> repository.delete(nonExistent));
+      assertEquals(2, repository.findAll().size());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/book/usecase/BookUseCaseTest.java

@@ -0,0 +1,231 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.usecase;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookDTO;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.entity.Book;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.exception.BookNotFoundException;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.exception.NotValidBookException;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.repository.BookRepository;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.*;
+
+@ExtendWith(MockitoExtension.class)
+class BookUseCaseTest {
+
+  @Mock
+  private BookRepository bookRepository;
+
+  @InjectMocks
+  private BookUseCase bookUseCase;
+
+  private UUID bookId;
+  private Book testBook;
+  private BookInfo validBookInfo;
+
+  @BeforeEach
+  void setUp() {
+    bookId = UUID.randomUUID();
+    testBook = Book.builder()
+        .id(bookId)
+        .isbn("9782016289308")
+        .title("Le Petit Prince")
+        .author("Antoine de Saint-Exupéry")
+        .publisher("Gallimard")
+        .publicationDate(LocalDate.of(1943, 4, 6))
+        .price(new BigDecimal("12.90"))
+        .stock(10)
+        .categories(List.of("Roman", "Jeunesse"))
+        .description("Un classique")
+        .language("FR")
+        .build();
+
+    validBookInfo = new BookInfo(
+        "9782016289308",
+        "Le Petit Prince",
+        "Antoine de Saint-Exupéry",
+        "Gallimard",
+        LocalDate.of(1943, 4, 6),
+        new BigDecimal("12.90"),
+        10,
+        List.of("Roman", "Jeunesse"),
+        "Un classique",
+        "FR"
+    );
+  }
+
+  @Nested
+  @DisplayName("Register book tests")
+  class RegisterBookTests {
+
+    @Test
+    @DisplayName("Should register book when valid data is provided")
+    void testRegisterBookWithValidData() throws NotValidBookException {
+      when(bookRepository.save(any(Book.class))).thenReturn(testBook);
+
+      String registeredIsbn = bookUseCase.registerBook(validBookInfo);
+
+      assertNotNull(registeredIsbn);
+      assertEquals("9782016289308", registeredIsbn);
+      verify(bookRepository, times(1)).save(any(Book.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when book data is not valid")
+    void testRegisterBookWithInvalidData() {
+      BookInfo invalidBookInfo = new BookInfo(
+          "",
+          "",
+          "",
+          "",
+          null,
+          BigDecimal.ZERO,
+          -1,
+          null,
+          "",
+          ""
+      );
+
+      assertThrows(NotValidBookException.class,
+          () -> bookUseCase.registerBook(invalidBookInfo));
+
+      verify(bookRepository, never()).save(any(Book.class));
+    }
+  }
+
+  @Nested
+  @DisplayName("Find book tests")
+  class FindBookTests {
+
+    @Test
+    @DisplayName("Should return book when ISBN exists")
+    void testFindBookByIsbn() {
+      when(bookRepository.findByIsbn("9782016289308")).thenReturn(Optional.of(testBook));
+
+      Optional<BookDTO> foundBook = bookUseCase.findBookByIsbn("9782016289308");
+
+      assertTrue(foundBook.isPresent());
+      assertEquals(testBook.getId(), foundBook.get().getId());
+      assertEquals(testBook.getTitle(), foundBook.get().getTitle());
+      verify(bookRepository, times(1)).findByIsbn("9782016289308");
+    }
+
+    @Test
+    @DisplayName("Should return empty Optional when ISBN doesn't exist")
+    void testFindBookByIsbnNotFound() {
+      when(bookRepository.findByIsbn("9999999999999")).thenReturn(Optional.empty());
+
+      Optional<BookDTO> foundBook = bookUseCase.findBookByIsbn("9999999999999");
+
+      assertTrue(foundBook.isEmpty());
+      verify(bookRepository, times(1)).findByIsbn("9999999999999");
+    }
+  }
+
+  @Nested
+  @DisplayName("Update book tests")
+  class UpdateBookTests {
+
+    @Test
+    @DisplayName("Should update book when valid data is provided")
+    void testUpdateBookWithValidData() throws BookNotFoundException, NotValidBookException {
+      when(bookRepository.findById(bookId)).thenReturn(Optional.of(testBook));
+
+      Book updatedBook = Book.builder()
+          .id(bookId)
+          .isbn("9782070409189")
+          .title("L'Étranger")
+          .author("Albert Camus")
+          .publisher("Gallimard")
+          .publicationDate(LocalDate.of(1942, 5, 19))
+          .price(new BigDecimal("9.50"))
+          .stock(10)
+          .categories(List.of("Roman"))
+          .description("Roman philosophique")
+          .language("FR")
+          .build();
+
+      when(bookRepository.save(any(Book.class))).thenReturn(updatedBook);
+
+      BookInfo updateInfo = new BookInfo(
+          "9782070409189",
+          "L'Étranger",
+          "Albert Camus",
+          "Gallimard",
+          LocalDate.of(1942, 5, 19),
+          new BigDecimal("9.50"),
+          99,
+          List.of("Roman"),
+          "Roman philosophique",
+          "FR"
+      );
+
+      BookDTO result = bookUseCase.updateBook(bookId, updateInfo);
+
+      assertNotNull(result);
+      assertEquals(bookId, result.getId());
+      assertEquals("L'Étranger", result.getTitle());
+      assertEquals("9782070409189", result.getIsbn());
+      assertEquals(10, result.getStock());
+      verify(bookRepository, times(1)).findById(bookId);
+      verify(bookRepository, times(1)).save(any(Book.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when book ID doesn't exist")
+    void testUpdateBookNotFound() {
+      UUID nonExistentId = UUID.randomUUID();
+      when(bookRepository.findById(nonExistentId)).thenReturn(Optional.empty());
+
+      assertThrows(BookNotFoundException.class,
+          () -> bookUseCase.updateBook(nonExistentId, validBookInfo));
+
+      verify(bookRepository, times(1)).findById(nonExistentId);
+      verify(bookRepository, never()).save(any(Book.class));
+    }
+  }
+
+  @Nested
+  @DisplayName("Delete book tests")
+  class DeleteBookTests {
+
+    @Test
+    @DisplayName("Should delete book when ID exists")
+    void testDeleteBook() throws BookNotFoundException {
+      when(bookRepository.findById(bookId)).thenReturn(Optional.of(testBook));
+
+      assertDoesNotThrow(() -> bookUseCase.deleteBook(bookId));
+
+      verify(bookRepository, times(1)).findById(bookId);
+      verify(bookRepository, times(1)).delete(testBook);
+    }
+
+    @Test
+    @DisplayName("Should throw exception when deleting unknown book")
+    void testDeleteBookNotFound() {
+      UUID nonExistentId = UUID.randomUUID();
+      when(bookRepository.findById(nonExistentId)).thenReturn(Optional.empty());
+
+      assertThrows(BookNotFoundException.class,
+          () -> bookUseCase.deleteBook(nonExistentId));
+
+      verify(bookRepository, times(1)).findById(nonExistentId);
+      verify(bookRepository, never()).delete(any(Book.class));
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/book/validator/BookValidatorTest.java

@@ -0,0 +1,184 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.book.validator;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.BookInfo;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.exception.NotValidBookException;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class BookValidatorTest {
+
+  private BookInfo validBook() {
+    return new BookInfo(
+        "9782016289308",
+        "Le Petit Prince",
+        "Antoine de Saint-Exupéry",
+        "Gallimard",
+        LocalDate.of(1943, 4, 6),
+        new BigDecimal("12.90"),
+        10,
+        List.of("Roman"),
+        "Un classique",
+        "FR"
+    );
+  }
+
+  @Test
+  @DisplayName("Should validate book with valid data")
+  void testValidateValidBook() {
+    assertDoesNotThrow(() -> BookValidator.validate(validBook()));
+  }
+
+  @Nested
+  @DisplayName("ISBN validation tests")
+  class IsbnValidationTests {
+
+    @Test
+    @DisplayName("Should throw exception when ISBN is blank")
+    void testValidateBlankIsbn() {
+      BookInfo book = new BookInfo("", "Titre", "Auteur", "Editeur",
+          LocalDate.now(), new BigDecimal("10.00"), 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.ISBN_IS_NOT_VALID, exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {"123456", "978201628930", "97820162893088", "abcdefghijklm", "978-016289308"})
+    @DisplayName("Should throw exception when ISBN format is invalid")
+    void testValidateInvalidIsbnFormat(String invalidIsbn) {
+      BookInfo book = new BookInfo(invalidIsbn, "Titre", "Auteur", "Editeur",
+          LocalDate.now(), new BigDecimal("10.00"), 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.ISBN_IS_NOT_VALID, exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {"9782016289308", "9782070409189", "9782253006329"})
+    @DisplayName("Should validate when ISBN has exactly 13 digits")
+    void testValidateValidIsbn(String validIsbn) {
+      BookInfo book = new BookInfo(validIsbn, "Titre", "Auteur", "Editeur",
+          LocalDate.now(), new BigDecimal("10.00"), 1, List.of("Roman"), "Desc", "FR");
+
+      assertDoesNotThrow(() -> BookValidator.validate(book));
+    }
+  }
+
+  @Nested
+  @DisplayName("Title validation tests")
+  class TitleValidationTests {
+
+    @Test
+    @DisplayName("Should throw exception when title is blank")
+    void testValidateBlankTitle() {
+      BookInfo book = new BookInfo("9782016289308", "", "Auteur", "Editeur",
+          LocalDate.now(), new BigDecimal("10.00"), 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.TITLE_CANNOT_BE_BLANK, exception.getMessage());
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {" ", "  ", "\t", "\n"})
+    @DisplayName("Should throw exception when title contains only whitespace")
+    void testValidateWhitespaceTitle(String whitespace) {
+      BookInfo book = new BookInfo("9782016289308", whitespace, "Auteur", "Editeur",
+          LocalDate.now(), new BigDecimal("10.00"), 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.TITLE_CANNOT_BE_BLANK, exception.getMessage());
+    }
+  }
+
+  @Nested
+  @DisplayName("Author validation tests")
+  class AuthorValidationTests {
+
+    @Test
+    @DisplayName("Should throw exception when author is blank")
+    void testValidateBlankAuthor() {
+      BookInfo book = new BookInfo("9782016289308", "Titre", "", "Editeur",
+          LocalDate.now(), new BigDecimal("10.00"), 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.AUTHOR_CANNOT_BE_BLANK, exception.getMessage());
+    }
+  }
+
+  @Nested
+  @DisplayName("Publisher validation tests")
+  class PublisherValidationTests {
+
+    @Test
+    @DisplayName("Should throw exception when publisher is blank")
+    void testValidateBlankPublisher() {
+      BookInfo book = new BookInfo("9782016289308", "Titre", "Auteur", "",
+          LocalDate.now(), new BigDecimal("10.00"), 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.PUBLISHER_CANNOT_BE_BLANK, exception.getMessage());
+    }
+  }
+
+  @Nested
+  @DisplayName("Price validation tests")
+  class PriceValidationTests {
+
+    @Test
+    @DisplayName("Should throw exception when price is negative")
+    void testValidateNegativePrice() {
+      BookInfo book = new BookInfo("9782016289308", "Titre", "Auteur", "Editeur",
+          LocalDate.now(), new BigDecimal("-5.00"), 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.PRICE_MUST_BE_POSITIVE, exception.getMessage());
+    }
+
+    @Test
+    @DisplayName("Should throw exception when price is zero")
+    void testValidateZeroPrice() {
+      BookInfo book = new BookInfo("9782016289308", "Titre", "Auteur", "Editeur",
+          LocalDate.now(), BigDecimal.ZERO, 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.PRICE_MUST_BE_POSITIVE, exception.getMessage());
+    }
+
+    @Test
+    @DisplayName("Should throw exception when price is null")
+    void testValidateNullPrice() {
+      BookInfo book = new BookInfo("9782016289308", "Titre", "Auteur", "Editeur",
+          LocalDate.now(), null, 1, List.of("Roman"), "Desc", "FR");
+
+      NotValidBookException exception = assertThrows(NotValidBookException.class,
+          () -> BookValidator.validate(book));
+
+      assertEquals(BookValidator.PRICE_MUST_BE_POSITIVE, exception.getMessage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/order/converter/OrderConverterTest.java

@@ -0,0 +1,90 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.converter;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.order.*;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.LigneCommande;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.Order;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.util.List;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+ 
+@DisplayName("OrderConverter Unit Tests")
+class OrderConverterTest {
+ 
+  private final UUID clientId = UUID.randomUUID();
+  private final UUID livreId = UUID.randomUUID();
+  private final AdresseLivraison adresse = new AdresseLivraison("1 rue de Paris", "Paris", "75001", "France");
+ 
+  @Nested
+  @DisplayName("toDomain() method tests")
+  class ToDomainTests {
+ 
+    @Test
+    @DisplayName("Should convert OrderInfo to Order domain object")
+    void shouldConvertOrderInfoToDomain() {
+      OrderInfo orderInfo = new OrderInfo(
+          clientId,
+          List.of(new LigneCommandeInfo(livreId, 2)),
+          adresse,
+          ModePaiement.CB
+      );
+ 
+      List<LigneCommande> lignes = List.of(
+          LigneCommande.builder()
+              .livreId(livreId)
+              .quantite(2)
+              .prixUnitaire(new BigDecimal("12.90"))
+              .build()
+      );
+ 
+      Order result = OrderConverter.toDomain(orderInfo, lignes, new BigDecimal("25.80"), 25);
+ 
+      assertNotNull(result);
+      assertEquals(clientId, result.getClientId());
+      assertEquals(adresse, result.getAdresseLivraison());
+      assertEquals(ModePaiement.CB, result.getModePaiement());
+      assertEquals(new BigDecimal("25.80"), result.getMontantTotal());
+      assertEquals(25, result.getPointsFideliteGagnes());
+      assertEquals(1, result.getLignesCommande().size());
+    }
+ 
+    @Test
+    @DisplayName("Should have null ID after toDomain (set by repository)")
+    void shouldHaveNullIdAfterToDomain() {
+      OrderInfo orderInfo = new OrderInfo(clientId, List.of(new LigneCommandeInfo(livreId, 1)), adresse, ModePaiement.CB);
+ 
+      Order result = OrderConverter.toDomain(orderInfo, List.of(), BigDecimal.ZERO, 0);
+ 
+      assertNull(result.getId());
+    }
+  }
+ 
+  @Nested
+  @DisplayName("toDTO() method tests")
+  class ToDTOTests {
+ 
+    @Test
+    @DisplayName("Should convert Order domain object to OrderDTO with all fields mapped correctly")
+    void shouldConvertOrderToDTO() {
+      UUID orderId = UUID.randomUUID();
+      Order order = Order.builder()
+          .id(orderId)
+          .clientId(clientId)
+          .montantTotal(new BigDecimal("25.80"))
+          .pointsFideliteGagnes(25)
+          .build();
+ 
+      OrderDTO result = OrderConverter.toDTO(order);
+ 
+      assertNotNull(result);
+      assertEquals(orderId, result.getCommandeId());
+      assertEquals(new BigDecimal("25.80"), result.getMontantTotal());
+      assertEquals(25, result.getPointsFideliteGagnes());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/order/entity/OrderTest.java

@@ -0,0 +1,81 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.entity;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.order.AdresseLivraison;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.ModePaiement;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.util.List;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+ 
+class OrderTest {
+ 
+  @Test
+  @DisplayName("Builder should create a valid Order instance")
+  void testOrderBuilder() {
+    UUID id = UUID.randomUUID();
+    UUID clientId = UUID.randomUUID();
+    AdresseLivraison adresse = new AdresseLivraison("1 rue de Paris", "Paris", "75001", "France");
+ 
+    Order order = Order.builder()
+        .id(id)
+        .clientId(clientId)
+        .adresseLivraison(adresse)
+        .modePaiement(ModePaiement.CB)
+        .montantTotal(new BigDecimal("25.80"))
+        .pointsFideliteGagnes(25)
+        .lignesCommande(List.of())
+        .build();
+ 
+    assertEquals(id, order.getId());
+    assertEquals(clientId, order.getClientId());
+    assertEquals(adresse, order.getAdresseLivraison());
+    assertEquals(ModePaiement.CB, order.getModePaiement());
+    assertEquals(new BigDecimal("25.80"), order.getMontantTotal());
+    assertEquals(25, order.getPointsFideliteGagnes());
+  }
+ 
+  @Test
+  @DisplayName("setRandomUUID should set a new non-null UUID")
+  void testSetRandomUUID() {
+    Order order = Order.builder().build();
+    UUID originalId = order.getId();
+ 
+    order.setRandomUUID();
+ 
+    assertNotNull(order.getId());
+    assertNotEquals(originalId, order.getId());
+  }
+ 
+  @Test
+  @DisplayName("Two setRandomUUID calls should produce different UUIDs")
+  void testSetRandomUUIDTwice() {
+    Order order = Order.builder().build();
+    order.setRandomUUID();
+    UUID firstId = order.getId();
+ 
+    order.setRandomUUID();
+    UUID secondId = order.getId();
+ 
+    assertNotEquals(firstId, secondId);
+  }
+ 
+  @Test
+  @DisplayName("Builder should create a valid LigneCommande instance")
+  void testLigneCommandeBuilder() {
+    UUID livreId = UUID.randomUUID();
+ 
+    LigneCommande ligne = LigneCommande.builder()
+        .livreId(livreId)
+        .quantite(3)
+        .prixUnitaire(new BigDecimal("12.90"))
+        .build();
+ 
+    assertEquals(livreId, ligne.getLivreId());
+    assertEquals(3, ligne.getQuantite());
+    assertEquals(new BigDecimal("12.90"), ligne.getPrixUnitaire());
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/order/exception/NotValidOrderExceptionTest.java

@@ -0,0 +1,62 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.exception;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+ 
+class NotValidOrderExceptionTest {
+ 
+  @Test
+  @DisplayName("Exception should be created with the provided message")
+  void testExceptionCreation() {
+    String errorMessage = "Order data is not valid";
+ 
+    NotValidOrderException exception = new NotValidOrderException(errorMessage);
+ 
+    assertEquals(errorMessage, exception.getMessage());
+  }
+ 
+  @ParameterizedTest
+  @ValueSource(strings = {
+      "Client id cannot be null",
+      "Order must have at least one item",
+      "Quantity must be positive",
+      "Payment method cannot be null",
+      "Delivery address cannot be null"
+  })
+  @DisplayName("Exception should handle different validation messages")
+  void testExceptionWithDifferentMessages(String errorMessage) {
+    NotValidOrderException exception = new NotValidOrderException(errorMessage);
+ 
+    assertEquals(errorMessage, exception.getMessage());
+  }
+ 
+  @Test
+  @DisplayName("Exception should be properly thrown and caught")
+  void testExceptionCanBeThrownAndCaught() {
+    String errorMessage = "Order must have at least one item";
+ 
+    Exception exception = assertThrows(NotValidOrderException.class, () -> {
+      throw new NotValidOrderException(errorMessage);
+    });
+ 
+    assertEquals(errorMessage, exception.getMessage());
+  }
+ 
+  @Test
+  @DisplayName("Exception should be catchable as a general Exception")
+  void testExceptionInheritance() {
+    String errorMessage = "Quantity must be positive";
+ 
+    try {
+      throw new NotValidOrderException(errorMessage);
+    } catch (Exception e) {
+      assertEquals(NotValidOrderException.class, e.getClass());
+      assertEquals(errorMessage, e.getMessage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/order/exception/OrderNotFoundExceptionTest.java

@@ -0,0 +1,48 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.exception;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+ 
+class OrderNotFoundExceptionTest {
+ 
+  @Test
+  @DisplayName("Exception message should contain the UUID provided")
+  void testExceptionMessageContainsUUID() {
+    UUID uuid = UUID.randomUUID();
+ 
+    OrderNotFoundException exception = new OrderNotFoundException(uuid);
+ 
+    String expectedMessage = String.format("The order with id %s does not exist", uuid);
+    assertEquals(expectedMessage, exception.getMessage());
+  }
+ 
+  @Test
+  @DisplayName("Exception should use the correct constant message format")
+  void testExceptionUsesConstantMessageFormat() {
+    UUID uuid = UUID.randomUUID();
+ 
+    OrderNotFoundException exception = new OrderNotFoundException(uuid);
+ 
+    assertEquals("The order with id {0} does not exist",
+        OrderNotFoundException.THE_ORDER_WITH_ID_DOES_NOT_EXIST_MESSAGE);
+    assertTrue(exception.getMessage().contains(uuid.toString()));
+  }
+ 
+  @Test
+  @DisplayName("Exception should be properly thrown and caught")
+  void testExceptionCanBeThrownAndCaught() {
+    UUID uuid = UUID.randomUUID();
+ 
+    try {
+      throw new OrderNotFoundException(uuid);
+    } catch (OrderNotFoundException e) {
+      String expectedMessage = String.format("The order with id %s does not exist", uuid);
+      assertEquals(expectedMessage, e.getMessage());
+    }
+  }
+}

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/order/repository/OrderRepositoryTest.java

@@ -0,0 +1,202 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.repository;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.order.AdresseLivraison;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.ModePaiement;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.Order;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+
+import java.math.BigDecimal;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+ 
+class OrderRepositoryTest {
+ 
+  private OrderRepository repository;
+  private Order order1;
+  private Order order2;
+  private UUID clientId1;
+  private UUID clientId2;
+ 
+  @BeforeEach
+  void setUp() {
+    repository = new OrderRepository();
+    clientId1 = UUID.randomUUID();
+    clientId2 = UUID.randomUUID();
+ 
+    AdresseLivraison adresse = new AdresseLivraison("1 rue de Paris", "Paris", "75001", "France");
+ 
+    order1 = Order.builder()
+        .clientId(clientId1)
+        .adresseLivraison(adresse)
+        .modePaiement(ModePaiement.CB)
+        .montantTotal(new BigDecimal("25.80"))
+        .pointsFideliteGagnes(25)
+        .lignesCommande(List.of())
+        .build();
+    order1.setRandomUUID();
+ 
+    order2 = Order.builder()
+        .clientId(clientId2)
+        .adresseLivraison(adresse)
+        .modePaiement(ModePaiement.PAYPAL)
+        .montantTotal(new BigDecimal("9.50"))
+        .pointsFideliteGagnes(9)
+        .lignesCommande(List.of())
+        .build();
+    order2.setRandomUUID();
+  }
+ 
+  @Test
+  @DisplayName("New repository should be empty")
+  void testNewRepositoryIsEmpty() {
+    assertTrue(repository.findAll().isEmpty());
+    assertEquals(0, repository.findAll().size());
+  }
+ 
+  @Nested
+  @DisplayName("Save operations")
+  class SaveOperations {
+ 
+    @Test
+    @DisplayName("Save should add a new order")
+    void testSaveNewOrder() {
+      Order saved = repository.save(order1);
+ 
+      assertEquals(1, repository.findAll().size());
+      assertEquals(order1.getId(), saved.getId());
+    }
+ 
+    @Test
+    @DisplayName("Save should update existing order with same ID")
+    void testSaveUpdatesExistingOrder() {
+      repository.save(order1);
+      UUID id = order1.getId();
+ 
+      Order updatedOrder = Order.builder()
+          .id(id)
+          .clientId(clientId1)
+          .adresseLivraison(new AdresseLivraison("2 rue de Lyon", "Lyon", "69001", "France"))
+          .modePaiement(ModePaiement.PAYPAL)
+          .montantTotal(new BigDecimal("50.00"))
+          .pointsFideliteGagnes(50)
+          .lignesCommande(List.of())
+          .build();
+ 
+      Order saved = repository.save(updatedOrder);
+ 
+      assertEquals(1, repository.findAll().size());
+      assertEquals(id, saved.getId());
+      assertEquals(new BigDecimal("50.00"), saved.getMontantTotal());
+    }
+ 
+    @Test
+    @DisplayName("Save multiple orders should add all of them")
+    void testSaveMultipleOrders() {
+      repository.save(order1);
+      repository.save(order2);
+ 
+      assertEquals(2, repository.findAll().size());
+    }
+  }
+ 
+  @Nested
+  @DisplayName("Find operations")
+  class FindOperations {
+ 
+    @BeforeEach
+    void setUpOrders() {
+      repository.save(order1);
+      repository.save(order2);
+    }
+ 
+    @Test
+    @DisplayName("FindAll should return all orders")
+    void testFindAll() {
+      assertEquals(2, repository.findAll().size());
+    }
+ 
+    @Test
+    @DisplayName("FindById should return order with matching ID")
+    void testFindById() {
+      Optional<Order> found = repository.findById(order1.getId());
+ 
+      assertTrue(found.isPresent());
+      assertEquals(order1.getId(), found.get().getId());
+    }
+ 
+    @Test
+    @DisplayName("FindById should return empty Optional when ID doesn't exist")
+    void testFindByIdNotFound() {
+      Optional<Order> found = repository.findById(UUID.randomUUID());
+ 
+      assertTrue(found.isEmpty());
+    }
+ 
+    @Test
+    @DisplayName("FindByClientId should return all orders for a client")
+    void testFindByClientId() {
+      List<Order> found = repository.findByClientId(clientId1);
+ 
+      assertEquals(1, found.size());
+      assertEquals(order1.getId(), found.getFirst().getId());
+    }
+ 
+    @Test
+    @DisplayName("ExistsById should return true when ID exists")
+    void testExistsByIdExists() {
+      assertTrue(repository.existsById(order1.getId()));
+    }
+ 
+    @Test
+    @DisplayName("ExistsById should return false when ID doesn't exist")
+    void testExistsByIdNotExists() {
+      assertFalse(repository.existsById(UUID.randomUUID()));
+    }
+  }
+ 
+  @Nested
+  @DisplayName("Delete operations")
+  class DeleteOperations {
+ 
+    @BeforeEach
+    void setUpOrders() {
+      repository.save(order1);
+      repository.save(order2);
+    }
+ 
+    @Test
+    @DisplayName("Delete should remove the specified order")
+    void testDelete() {
+      repository.delete(order1);
+ 
+      assertEquals(1, repository.findAll().size());
+      assertFalse(repository.findAll().contains(order1));
+      assertTrue(repository.findAll().contains(order2));
+    }
+ 
+    @Test
+    @DisplayName("DeleteAll should remove all orders")
+    void testDeleteAll() {
+      repository.deleteAll();
+ 
+      assertTrue(repository.findAll().isEmpty());
+    }
+ 
+    @Test
+    @DisplayName("Delete should not throw exception when order doesn't exist")
+    void testDeleteNonExistentOrder() {
+      Order nonExistent = Order.builder().build();
+      nonExistent.setRandomUUID();
+ 
+      assertDoesNotThrow(() -> repository.delete(nonExistent));
+      assertEquals(2, repository.findAll().size());
+    }
+  }
+}
+ 

src/test/java/fr/iut_fbleau/but3/dev62/mylibrary/order/usecase/OrderUseCaseTest.java

@@ -0,0 +1,223 @@
+package fr.iut_fbleau.but3.dev62.mylibrary.order.usecase;
+
+import fr.iut_fbleau.but3.dev62.mylibrary.book.entity.Book;
+import fr.iut_fbleau.but3.dev62.mylibrary.book.repository.BookRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.entity.Customer;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.exception.CustomerNotFoundException;
+import fr.iut_fbleau.but3.dev62.mylibrary.customer.repository.CustomerRepository;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.*;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.entity.Order;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.exception.NotValidOrderException;
+import fr.iut_fbleau.but3.dev62.mylibrary.order.repository.OrderRepository;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.Optional;
+import java.util.UUID;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.*;
+
+@ExtendWith(MockitoExtension.class)
+class OrderUseCaseTest {
+
+  @Mock
+  private OrderRepository orderRepository;
+
+  @Mock
+  private CustomerRepository customerRepository;
+
+  @Mock
+  private BookRepository bookRepository;
+
+  @InjectMocks
+  private OrderUseCase orderUseCase;
+
+  private UUID customerId;
+  private UUID bookId;
+  private Customer testCustomer;
+  private Book testBook;
+  private AdresseLivraison adresse;
+  private OrderInfo validOrderInfo;
+
+  @BeforeEach
+  void setUp() {
+    customerId = UUID.randomUUID();
+    bookId = UUID.randomUUID();
+
+    testCustomer = Customer.builder()
+        .id(customerId)
+        .firstName("Marie")
+        .lastName("Dupont")
+        .phoneNumber("0612345678")
+        .loyaltyPoints(100)
+        .build();
+
+    testBook = Book.builder()
+        .id(bookId)
+        .isbn("9782016289308")
+        .title("Le Petit Prince")
+        .author("Antoine de Saint-Exupery")
+        .publisher("Gallimard")
+        .publicationDate(LocalDate.of(1943, 4, 6))
+        .price(new BigDecimal("12.90"))
+        .stock(10)
+        .categories(List.of("Roman"))
+        .description("Un classique")
+        .language("FR")
+        .build();
+
+    adresse = new AdresseLivraison("1 rue de Paris", "Paris", "75001", "France");
+
+    validOrderInfo = new OrderInfo(
+        customerId,
+        List.of(new LigneCommandeInfo(bookId, 2)),
+        adresse,
+        ModePaiement.CB
+    );
+  }
+
+  @Nested
+  @DisplayName("PasserCommande tests")
+  class PasserCommandeTests {
+
+    @Test
+    @DisplayName("Should place order when valid data is provided")
+    void testPasserCommandeWithValidData() throws NotValidOrderException, CustomerNotFoundException {
+      when(customerRepository.findById(customerId)).thenReturn(Optional.of(testCustomer));
+      when(bookRepository.findById(bookId)).thenReturn(Optional.of(testBook));
+      when(customerRepository.save(any(Customer.class))).thenReturn(testCustomer);
+
+      UUID orderId = UUID.randomUUID();
+      Order savedOrder = Order.builder()
+          .id(orderId)
+          .clientId(customerId)
+          .montantTotal(new BigDecimal("25.80"))
+          .pointsFideliteGagnes(25)
+          .build();
+      when(orderRepository.save(any(Order.class))).thenReturn(savedOrder);
+
+      OrderDTO result = orderUseCase.passerCommande(validOrderInfo);
+
+      assertNotNull(result);
+      assertEquals(orderId, result.getCommandeId());
+      verify(orderRepository, times(1)).save(any(Order.class));
+      verify(customerRepository, times(1)).save(any(Customer.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when customer does not exist")
+    void testPasserCommandeWithUnknownCustomer() {
+      when(customerRepository.findById(customerId)).thenReturn(Optional.empty());
+
+      assertThrows(CustomerNotFoundException.class,
+          () -> orderUseCase.passerCommande(validOrderInfo));
+
+      verify(orderRepository, never()).save(any(Order.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when order has no items")
+    void testPasserCommandeWithNoItems() {
+      OrderInfo emptyOrder = new OrderInfo(customerId, List.of(), adresse, ModePaiement.CB);
+
+      assertThrows(NotValidOrderException.class,
+          () -> orderUseCase.passerCommande(emptyOrder));
+
+      verify(orderRepository, never()).save(any(Order.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when quantity is zero or negative")
+    void testPasserCommandeWithInvalidQuantity() {
+      OrderInfo invalidQty = new OrderInfo(
+          customerId,
+          List.of(new LigneCommandeInfo(bookId, 0)),
+          adresse,
+          ModePaiement.CB
+      );
+
+      assertThrows(NotValidOrderException.class,
+          () -> orderUseCase.passerCommande(invalidQty));
+
+      verify(orderRepository, never()).save(any(Order.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when clientId is null")
+    void testPasserCommandeWithNullClientId() {
+      OrderInfo nullClient = new OrderInfo(
+          null,
+          List.of(new LigneCommandeInfo(bookId, 1)),
+          adresse,
+          ModePaiement.CB
+      );
+
+      assertThrows(NotValidOrderException.class,
+          () -> orderUseCase.passerCommande(nullClient));
+
+      verify(orderRepository, never()).save(any(Order.class));
+    }
+
+    @Test
+    @DisplayName("Should throw exception when payment method is null")
+    void testPasserCommandeWithNullModePaiement() {
+      OrderInfo nullPayment = new OrderInfo(
+          customerId,
+          List.of(new LigneCommandeInfo(bookId, 1)),
+          adresse,
+          null
+      );
+
+      assertThrows(NotValidOrderException.class,
+          () -> orderUseCase.passerCommande(nullPayment));
+
+      verify(orderRepository, never()).save(any(Order.class));
+    }
+  }
+
+  @Nested
+  @DisplayName("FindOrder tests")
+  class FindOrderTests {
+
+    @Test
+    @DisplayName("Should return order when ID exists")
+    void testFindOrderById() {
+      UUID orderId = UUID.randomUUID();
+      Order order = Order.builder()
+          .id(orderId)
+          .clientId(customerId)
+          .montantTotal(new BigDecimal("25.80"))
+          .pointsFideliteGagnes(25)
+          .build();
+
+      when(orderRepository.findById(orderId)).thenReturn(Optional.of(order));
+
+      Optional<OrderDTO> result = orderUseCase.findOrderById(orderId);
+
+      assertTrue(result.isPresent());
+      assertEquals(orderId, result.get().getCommandeId());
+    }
+
+    @Test
+    @DisplayName("Should return empty Optional when ID does not exist")
+    void testFindOrderByIdNotFound() {
+      UUID nonExistentId = UUID.randomUUID();
+      when(orderRepository.findById(nonExistentId)).thenReturn(Optional.empty());
+
+      Optional<OrderDTO> result = orderUseCase.findOrderById(nonExistentId);
+
+      assertTrue(result.isEmpty());
+    }
+  }
+}