Add return feature

src/main/java/com/twu/biblioteca/App.java

@@ -20,14 +20,17 @@ public static void main(String[] args) {
                     bookPresenter.listBooks();
                     break;
                 case 2:
-                    System.out.println("What book do you want to checkout?");
+                    optionPresenter.askForCheckOut();
                     String bookTitle = user.readBookTitle();
                     bookPresenter.checkOut(bookTitle);
                     break;
+                case 3:
+                    optionPresenter.askForReturn();
+                    bookTitle = user.readBookTitle();
+                    bookPresenter.returnBook(bookTitle);
+                    break;
                 default:
-                    System.out.println("Select a valid option!");
-                    System.out.println();
-                    optionPresenter.showMenu();
+                    optionPresenter.sayInvalidOption();
             }
             optionPresenter.showMenu();
         }

src/main/java/com/twu/biblioteca/OptionPresenter.java

@@ -2,28 +2,41 @@
 
 import java.io.PrintStream;
 
-public class OptionPresenter {
+class OptionPresenter {
     private static final String WELCOME_MESSAGE = "Welcome to the Bangalore Public Library system";
     private static final String FANCY_LINE = "----------------------------------------------";
     private static final String END_OF_LINE = "\n";
 
     private final PrintStream output;
 
-    public OptionPresenter(PrintStream output) {
+    OptionPresenter(PrintStream output) {
         this.output = output;
     }
 
-    public void sayWelcome() {
+    void sayWelcome() {
         output.println(FANCY_LINE);
         output.println(WELCOME_MESSAGE);
         output.println(FANCY_LINE);
-        output.println(END_OF_LINE);
     }
 
-    public void showMenu() {
+    void showMenu() {
         output.println("Choose an option:");
         output.println("\t1. List books");
-        output.println("\t2. Checkout book");
+        output.println("\t2. Checkout a book");
+        output.println("\t3. Return a book");
         output.println("\t0. Exit");
     }
+
+    void askForCheckOut() {
+        output.println("What book do you want to checkout?");
+    }
+
+    void askForReturn() {
+        output.println("What book do you want to return?");
+    }
+
+    void sayInvalidOption() {
+        output.println("Select a valid option!");
+        System.out.println();
+    }
 }

src/main/java/com/twu/biblioteca/books/application/BookShelves.java

@@ -8,4 +8,6 @@ public interface BookShelves {
     Collection<BookInfo> listBooks();
 
     void checkOut(String bookTitle) throws BookNotFound;
+
+    void returnBook(String bookTitle) throws BookNotFound;
 }

src/main/java/com/twu/biblioteca/books/application/BookShelvesInteractor.java

@@ -27,6 +27,13 @@ public void checkOut(String bookTitle) {
         else throw new BookNotFound();
     }
 
+    @Override
+    public void returnBook(String bookTitle) {
+        if (this.books.containsKey(bookTitle))
+            this.books.get(bookTitle).returnCopy();
+        else throw new BookNotFound();
+    }
+
     public void preloadBooks() {
         BookInfo book1 = new BookInfoBuilder().withTitle("Harry Potter and the Philosopher's Stone").fromAuthor("J.K Rowling").publishedInYear(1997).build();
         BookInfo book2 = new BookInfoBuilder().withTitle("Game of Thrones - A Game of Thrones").fromAuthor("George R. Martin").publishedInYear(1994).build();

src/main/java/com/twu/biblioteca/books/core/BookInfo.java

@@ -43,4 +43,9 @@ public void checkOut() {
         if (this.isAvailable()) checkedOut = true;
         else throw new BookNotAvailable();
     }
+
+    public void returnCopy() {
+        if (this.isAvailable()) throw new NotAbleToReturnBook();
+        else checkedOut = false;
+    }
 }

src/main/java/com/twu/biblioteca/books/core/NotAbleToReturnBook.java

@@ -0,0 +1,4 @@
+package com.twu.biblioteca.books.core;
+
+public class NotAbleToReturnBook extends RuntimeException {
+}

src/main/java/com/twu/biblioteca/books/infrastructure/AbstractBookPresenter.java

@@ -4,4 +4,6 @@ public interface AbstractBookPresenter {
     void listBooks();
 
     void checkOut(String bookTitle);
+
+    void returnBook(String bookTitle);
 }

src/main/java/com/twu/biblioteca/books/infrastructure/BookPresenter.java

@@ -4,6 +4,7 @@
 import com.twu.biblioteca.books.application.BookShelves;
 import com.twu.biblioteca.books.core.BookInfo;
 import com.twu.biblioteca.books.core.BookNotAvailable;
+import com.twu.biblioteca.books.core.NotAbleToReturnBook;
 
 import java.io.PrintStream;
 import java.util.Comparator;
@@ -15,6 +16,9 @@ public class BookPresenter implements AbstractBookPresenter {
     private static final String FANCY_LINE = "----------------------------------------";
     private static final String HEADERS = "Title" + SPACE_BETWEEN_COLUMNS + "Author" + SPACE_BETWEEN_COLUMNS + "Publication year\n" + FANCY_LINE;
     private static final String THANK_YOU_FOR_CHECKING_OUT = "Thank you! Enjoy the book";
+    private static final String BOOK_NOT_AVAILABLE = "That book is not available";
+    private static final String THANK_YOU_FOR_RETURNING = "Thank you for returning the book";
+    private static final String NOT_VALID_BOOK = "That is not a valid book to return";
 
     private final BookShelves bookShelves;
     private final PrintStream output;
@@ -43,7 +47,17 @@ public void checkOut(String bookTitle) {
             bookShelves.checkOut(bookTitle);
             output.println(THANK_YOU_FOR_CHECKING_OUT);
         } catch (BookNotFound | BookNotAvailable e) {
-            output.println("That book is not available");
+            output.println(BOOK_NOT_AVAILABLE);
+        }
+    }
+
+    @Override
+    public void returnBook(String bookTitle) {
+        try {
+            bookShelves.returnBook(bookTitle);
+            output.println(THANK_YOU_FOR_RETURNING);
+        } catch (BookNotFound | NotAbleToReturnBook e) {
+            output.println(NOT_VALID_BOOK);
         }
     }
 }

src/test/java/com/twu/biblioteca/books/OptionPresenterShould.java → src/test/java/com/twu/biblioteca/OptionPresenterShould.java

@@ -1,6 +1,5 @@
-package com.twu.biblioteca.books;
+package com.twu.biblioteca;
 
-import com.twu.biblioteca.OptionPresenter;
 import org.junit.Before;
 import org.junit.Test;
 import org.mockito.InOrder;
@@ -32,19 +31,14 @@ public void showTwoFancyLinesWhenWelcoming() {
         verify(outMock, times(2)).println("----------------------------------------------");
     }
 
-    @Test
-    public void leaveALineAfterTheWelcome() {
-        optionPresenter.sayWelcome();
-        verify(outMock).println("\n");
-    }
-
     @Test
     public void showMenuOptions() {
         optionPresenter.showMenu();
         InOrder inOrder = inOrder(outMock);
         inOrder.verify(outMock).println("Choose an option:");
         inOrder.verify(outMock).println("\t1. List books");
-        inOrder.verify(outMock).println("\t2. Checkout book");
+        inOrder.verify(outMock).println("\t2. Checkout a book");
+        inOrder.verify(outMock).println("\t3. Return a book");
         inOrder.verify(outMock).println("\t0. Exit");
         verifyNoMoreInteractions(outMock);
     }

src/test/java/com/twu/biblioteca/books/application/BookShelvesInteractorShould.java

@@ -20,10 +20,14 @@ public void haveSomeBooksWhenPreloaded() {
     }
 
     @Test(expected = BookNotFound.class)
-    public void shouldThrowBookNotFoundWhenTryingToCheckOutABookThatIsNotAvailable() {
+    public void throwBookNotFoundWhenTryingToCheckOutABookThatIsNotAvailable() {
         BookShelvesInteractor bookShelves = new BookShelvesInteractor();
-        bookShelves.preloadBooks();
         bookShelves.checkOut("not existing book");
     }
 
+    @Test(expected = BookNotFound.class)
+    public void throwBookNotFoundWhenTryingToReturnABookThatIsNotAvailable() {
+        BookShelvesInteractor bookShelves = new BookShelvesInteractor();
+        bookShelves.returnBook("not existing book");
+    }
 }

src/test/java/com/twu/biblioteca/books/core/BookInfoShould.java

@@ -26,4 +26,18 @@ public void throwBookNotAvailableWhenTryingToCheckOutBeingNotAvailable() {
         book.checkOut();
         book.checkOut();
     }
+
+    @Test(expected = NotAbleToReturnBook.class)
+    public void throwNotAbleToReturnWhenTryingToReturnBeingAvailable() {
+        BookInfo book = new BookInfo("some title");
+        book.returnCopy();
+    }
+
+    @Test
+    public void beAvailableAfterReturned() {
+        BookInfo book = new BookInfo("some title");
+        book.checkOut();
+        book.returnCopy();
+        assertThat(book.isAvailable(), is(true));
+    }
 }

src/test/java/com/twu/biblioteca/books/infrastructure/BookPresenterShould.java

@@ -5,6 +5,7 @@
 import com.twu.biblioteca.books.application.BookShelvesInteractor;
 import com.twu.biblioteca.books.core.BookInfoBuilder;
 import com.twu.biblioteca.books.core.BookNotAvailable;
+import com.twu.biblioteca.books.core.NotAbleToReturnBook;
 import org.junit.Before;
 import org.junit.Test;
 import org.mockito.InOrder;
@@ -37,7 +38,7 @@ public void sayThereAreNoBooksInTheShelves() {
 
     @Test
     public void showTheHeadersBeforeAnyBookInfo() {
-        when(bookShelvesMock.listBooks()).thenReturn(Arrays.asList(
+        when(bookShelvesMock.listBooks()).thenReturn(Collections.singletonList(
                 new BookInfoBuilder()
                         .withTitle("Harry Potter and the Philosopher's Stone")
                         .fromAuthor("J.K. Rowling")
@@ -89,7 +90,7 @@ public void showBooksAlphabeticallySorted() {
 
     @Test
     public void notShowCheckOutBooks() {
-        when(bookShelvesMock.listBooks()).thenReturn(Arrays.asList(
+        when(bookShelvesMock.listBooks()).thenReturn(Collections.singletonList(
                 new BookInfoBuilder()
                         .withTitle("Harry Potter and the Philosopher's Stone")
                         .fromAuthor("J.K. Rowling")
@@ -103,7 +104,7 @@ public void notShowCheckOutBooks() {
 
     @Test
     public void sayThankYouWhenCheckingOutABook() {
-        when(bookShelvesMock.listBooks()).thenReturn(Arrays.asList(
+        when(bookShelvesMock.listBooks()).thenReturn(Collections.singletonList(
                 new BookInfoBuilder()
                         .withTitle("Harry Potter and the Philosopher's Stone")
                         .fromAuthor("J.K. Rowling")
@@ -126,4 +127,31 @@ public void sayTheBookIsNotAvailableWhenTheBookIsNotInTheShelves() {
         presenter.checkOut("Harry Potter and the Philosopher's Stone");
         verify(outMock).println("That book is not available");
     }
+
+    @Test
+    public void sayThanksForReturningABook() {
+        when(bookShelvesMock.listBooks()).thenReturn(Collections.singletonList(
+                new BookInfoBuilder()
+                        .withTitle("Harry Potter and the Philosopher's Stone")
+                        .fromAuthor("J.K. Rowling")
+                        .publishedInYear(1997)
+                        .checkedOut()
+                        .build()));
+        presenter.returnBook("Harry Potter and the Philosopher's Stone");
+        verify(outMock).println("Thank you for returning the book");
+    }
+
+    @Test
+    public void sayTheBookIsNotValidToReturnWhenBookIsNotFound() {
+        doThrow(BookNotFound.class).when(bookShelvesMock).returnBook(anyString());
+        presenter.returnBook("Harry Potter and the Philosopher's Stone");
+        verify(outMock).println("That is not a valid book to return");
+    }
+
+    @Test
+    public void sayTheBookIsNotValidToReturnWhenBookIsYetAvailable() {
+        doThrow(NotAbleToReturnBook.class).when(bookShelvesMock).returnBook(anyString());
+        presenter.returnBook("Harry Potter and the Philosopher's Stone");
+        verify(outMock).println("That is not a valid book to return");
+    }
 }