Belma Jakupovic - Mockito additional answers (#9041)

testing-modules/mockito-2/src/main/java/com/baeldung/mockito/additionalanswers/Book.java

@@ -0,0 +1,58 @@
+package com.baeldung.mockito.additionalanswers;
+
+public class Book {
+
+    private Long bookId;
+
+    private String title;
+
+    private String author;
+
+    private int numberOfPages;
+
+    public Book(String title, String author, int numberOfPages) {
+        this.title = title;
+        this.author = author;
+        this.numberOfPages = numberOfPages;
+    }
+
+    public Book(Long bookId, String title, String author, int numberOfPages) {
+        this.bookId = bookId;
+        this.title = title;
+        this.author = author;
+        this.numberOfPages = numberOfPages;
+    }
+
+    public Long getBookId() {
+        return bookId;
+    }
+
+    public void setBookId(Long bookId) {
+        this.bookId = bookId;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public String getAuthor() {
+        return author;
+    }
+
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public int getNumberOfPages() {
+        return numberOfPages;
+    }
+
+    public void setNumberOfPages(int numberOfPages) {
+        this.numberOfPages = numberOfPages;
+    }
+}
+

testing-modules/mockito-2/src/main/java/com/baeldung/mockito/additionalanswers/BookRepository.java

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+package com.baeldung.mockito.additionalanswers;
+
+public class BookRepository {
+    public Book getByBookId(Long bookId) {
+        return new Book(bookId, "To Kill a Mocking Bird", "Harper Lee", 256);
+    }
+
+    public Book save(Book book) {
+        return new Book(book.getBookId(), book.getTitle(), book.getAuthor(), book.getNumberOfPages());
+    }
+
+    public Book checkIfEquals(Book bookOne, Book bookTwo, Book bookThree) {
+        if (bookOne.equals(bookTwo) && bookTwo.equals(bookThree) && bookThree.equals(bookOne)) {
+            return bookOne;
+        } else return bookTwo;
+    }
+}

testing-modules/mockito-2/src/main/java/com/baeldung/mockito/additionalanswers/BookService.java

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+package com.baeldung.mockito.additionalanswers;
+
+public class BookService {
+    private final BookRepository bookRepository;
+
+    public BookService(BookRepository bookRepository) {
+        this.bookRepository = bookRepository;
+    }
+
+    public Book getByBookId(Long id) {
+        return bookRepository.getByBookId(id);
+    }
+
+    public Book save(Book book) {
+        return bookRepository.save(book);
+    }
+
+    public Book checkifEquals(Book book1, Book book2, Book book3) {
+        return bookRepository.checkIfEquals(book1, book2, book3);
+    }
+}
+

testing-modules/mockito-2/src/test/java/com/baeldung/mockito/additionalanswers/BookServiceUnitTest.java

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+package com.baeldung.mockito.additionalanswers;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.AdditionalAnswers;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.Mockito;
+import org.mockito.junit.MockitoJUnitRunner;
+import static org.junit.Assert.assertEquals;
+import static org.mockito.ArgumentMatchers.any;
+
+@RunWith(MockitoJUnitRunner.class)
+public class BookServiceUnitTest {
+    @InjectMocks
+    private BookService bookService;
+
+    @Mock
+    private BookRepository bookRepository;
+
+    @Test
+    public void givenSaveMethodMocked_whenSaveInvoked_ThenReturnFirstArgument_UnitTest() {
+        Book book = new Book("To Kill a Mocking Bird", "Harper Lee", 256);
+        Mockito.when(bookRepository.save(any(Book.class))).then(AdditionalAnswers.returnsFirstArg());
+
+        Book savedBook = bookService.save(book);
+
+        assertEquals(savedBook, book);
+    }
+
+    @Test
+    public void givenCheckifEqualsMethodMocked_whenCheckifEqualsInvoked_ThenReturnSecondArgument_UnitTest() {
+        Book book1 = new Book(1L, "The Stranger", "Albert Camus", 456);
+        Book book2 = new Book(2L, "Animal Farm", "George Orwell", 300);
+        Book book3 = new Book(3L, "Romeo and Juliet", "William Shakespeare", 200);
+
+        Mockito.when(bookRepository.checkIfEquals(any(Book.class), any(Book.class), any(Book.class))).then(AdditionalAnswers.returnsSecondArg());
+
+        Book secondBook = bookService.checkifEquals(book1, book2, book3);
+
+        assertEquals(secondBook, book2);
+    }
+
+    @Test
+    public void givenCheckifEqualsMethodMocked_whenCheckifEqualsInvoked_ThenReturnLastArgument_UnitTest() {
+        Book book1 = new Book(1L, "The Stranger", "Albert Camus", 456);
+        Book book2 = new Book(2L, "Animal Farm", "George Orwell", 300);
+        Book book3 = new Book(3L, "Romeo and Juliet", "William Shakespeare", 200);
+
+        Mockito.when(bookRepository.checkIfEquals(any(Book.class), any(Book.class), any(Book.class))).then(AdditionalAnswers.returnsLastArg());
+
+        Book lastBook = bookService.checkifEquals(book1, book2, book3);
+        assertEquals(lastBook, book3);
+    }
+
+    @Test
+    public void givenCheckifEqualsMethodMocked_whenCheckifEqualsInvoked_ThenReturnArgumentAtIndex_UnitTest() {
+        Book book1 = new Book(1L, "The Stranger", "Albert Camus", 456);
+        Book book2 = new Book(2L, "Animal Farm", "George Orwell", 300);
+        Book book3 = new Book(3L, "Romeo and Juliet", "William Shakespeare", 200);
+
+        Mockito.when(bookRepository.checkIfEquals(any(Book.class), any(Book.class), any(Book.class))).then(AdditionalAnswers.returnsArgAt(1));
+
+        Book bookOnIndex = bookService.checkifEquals(book1, book2, book3);
+
+        assertEquals(bookOnIndex, book2);
+    }
+}