Renamed the randomBooks() method to generate() & added some javadocs for the public methods.

.idea/runConfigurations/All_Unit_Tests.xml

@@ -15,7 +15,7 @@
     <option name="TEST_OBJECT" value="directory" />
     <option name="VM_PARAMETERS" value="-ea" />
     <option name="PARAMETERS" value="" />
-    <option name="WORKING_DIRECTORY" value="file://$MODULE_DIR$" />
+    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/app" />
     <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">

app/build.gradle

@@ -34,7 +34,7 @@ dependencies {
     testCompile 'junit:junit:4.12'
     testCompile 'info.cukes:cucumber-java:1.2.4'
     testCompile 'info.cukes:cucumber-junit:1.2.4'
-    testCompile 'org.mockito:mockito-core:1.+'
+    testCompile 'org.mockito:mockito-core:2.5.5'
 
     compile 'com.android.support:appcompat-v7:25.0.1'
     compile 'com.android.support:recyclerview-v7:25.0.1'

app/src/main/java/com/codemate/booklibrary/data/RandomBookGenerator.java

@@ -35,7 +35,12 @@ public class RandomBookGenerator {
             "Johnson", "Springsteen", "Kauffman", "Schmidt", "Jokinen"
     };
 
-    public static List<Book> randomBooks(int howMany) {
+    /**
+     * Generates multiple random books.
+     * @param howMany how many random books should the generator generate.
+     * @return a list that has as many books as the parameter howMany specifies.
+     */
+    public static List<Book> generate(int howMany) {
         List<Book> books = new ArrayList<>();
 
         for (int i = 0; i < howMany; i++) {
@@ -45,6 +50,9 @@ public class RandomBookGenerator {
         return books;
     }
 
+    /**
+     * Generates a random book.
+     */
     public static Book randomBook() {
         String title = randomTitle();
         String author = randomAuthor();
@@ -57,14 +65,14 @@ public class RandomBookGenerator {
         String subject = RandomUtils.randomFromArray(SUBJECTS);
         String secondWord = RandomUtils.randomFromArray(SECOND_WORDS);
 
-        return subject + " " + secondWord;
+        return String.format("%s %s", subject, secondWord);
     }
 
     private static String randomAuthor() {
         String firstName = RandomUtils.randomFromArray(FIRST_NAMES);
         String lastName = RandomUtils.randomFromArray(LAST_NAMES);
 
-        return firstName + " " + lastName;
+        return String.format("%s %s", firstName, lastName);
     }
 
     private static Date randomDate() {

app/src/main/java/com/codemate/booklibrary/ui/MainActivity.java

@@ -13,7 +13,6 @@ import com.codemate.booklibrary.R;
 import java.util.List;
 
 public class MainActivity extends AppCompatActivity implements MainView, SearchView.OnQueryTextListener {
-
     private MainPresenter presenter;
     private BookAdapter bookAdapter;
 

app/src/main/java/com/codemate/booklibrary/ui/MainPresenter.java

@@ -27,7 +27,7 @@ public class MainPresenter {
         // Populate the library with fake dummy data. In a real app
         // we would have an interactor that would fetch the books from
         // a real API.
-        List<Book> books = RandomBookGenerator.randomBooks(45);
+        List<Book> books = RandomBookGenerator.generate(45);
         library.addBooks(books);
 
         loadBooks(library.getAllBooks());

app/src/test/java/com/codemate/booklibrary/data/LibraryTest.java

@@ -11,7 +11,7 @@ import java.util.List;
 public class LibraryTest {
     @Test
     public void addMultipleBooks_PersistsThemInLibrary() {
-        List<Book> books = RandomBookGenerator.randomBooks(3);
+        List<Book> books = RandomBookGenerator.generate(3);
         Library library = new Library();
         library.addBooks(books);
 

app/src/test/java/com/codemate/booklibrary/data/RandomBookGeneratorTest.java

@@ -14,7 +14,7 @@ import static org.junit.Assert.assertNotNull;
 public class RandomBookGeneratorTest {
     @Test
     public void generatingRandomBooks_ReturnsNonEmptyBookList() {
-        List<Book> books = RandomBookGenerator.randomBooks(15);
+        List<Book> books = RandomBookGenerator.generate(15);
 
         assertEquals(15, books.size());
 

app/src/test/java/com/codemate/booklibrary/ui/MainPresenterTest.java

@@ -19,7 +19,6 @@ import static org.mockito.Mockito.when;
  * Created by ironman on 02/09/16.
  */
 public class MainPresenterTest {
-
     @Mock
     private MainView mainView;
 
@@ -32,14 +31,14 @@ public class MainPresenterTest {
     @Before
     public void setUp() {
         MockitoAnnotations.initMocks(this);
+
         presenter = new MainPresenter(mainView, library);
-        randomBooks = RandomBookGenerator.randomBooks(5);
+        randomBooks = RandomBookGenerator.generate(5);
     }
 
     @Test
     public void searchForBooks_ShowsThemInUI() {
-        when(library.search(anyString()))
+        when(library.search(anyString())).thenReturn(randomBooks);
-                .thenReturn(randomBooks);
         presenter.searchForBooks("test_search");
 
         verify(mainView).showBooks(randomBooks);
@@ -47,8 +46,7 @@ public class MainPresenterTest {
 
     @Test
     public void loadAllBooks_ShowsThemInUI() {
-        when(library.getAllBooks())
+        when(library.getAllBooks()).thenReturn(randomBooks);
-                .thenReturn(randomBooks);
         presenter.loadAllBooks();
 
         verify(mainView).showBooks(randomBooks);