Add more tests and refactor

src/main/java/edu/uastw/App.java

@@ -1,5 +1,14 @@
 package edu.uastw;
 
+import edu.uastw.library.*;
+import edu.uastw.library.decorators.DecreaseBooksCapacityDecorator;
+import edu.uastw.library.decorators.IncreaseBooksCapacityDecorator;
+import edu.uastw.library.decorators.LibraryDecorator;
+import edu.uastw.library.items.Book;
+import edu.uastw.library.items.ItemType;
+import edu.uastw.library.items.LibraryItem;
+import edu.uastw.library.items.Magazine;
+
 import java.util.Iterator;
 
 public class App {

src/main/java/edu/uastw/library/Library.java

@@ -1,4 +1,7 @@
-package edu.uastw;
+package edu.uastw.library;
+
+import edu.uastw.library.items.ItemType;
+import edu.uastw.library.items.LibraryItem;
 
 import java.util.ArrayList;
 import java.util.Iterator;
@@ -46,21 +49,7 @@ public class Library implements Iterable<LibraryItem> {
 
     @Override
     public Iterator<LibraryItem> iterator() {
-        return new LibraryItemIterator();
-    }
-
-    private class LibraryItemIterator implements Iterator<LibraryItem> {
-        private int currentIndex = 0;
-
-        @Override
-        public boolean hasNext() {
-            return currentIndex < booksCapacity;
-        }
-
-        @Override
-        public LibraryItem next() {
-            return libraryItems.get(currentIndex++);
-        }
+        return libraryItems.stream().limit(booksCapacity).iterator();
     }
 
     public Iterator<LibraryItem> customTypeIterator(ItemType type) {

src/main/java/edu/uastw/library/LibraryBuilder.java

@@ -1,4 +1,6 @@
-package edu.uastw;
+package edu.uastw.library;
+
+import edu.uastw.library.items.LibraryItem;
 
 public class LibraryBuilder {
     private final Library library;

src/main/java/edu/uastw/library/decorators/DecreaseBooksCapacityDecorator.java

@@ -1,4 +1,6 @@
-package edu.uastw;
+package edu.uastw.library.decorators;
+
+import edu.uastw.library.Library;
 
 public class DecreaseBooksCapacityDecorator extends LibraryDecorator {
     private final int reducedCapacity;

src/main/java/edu/uastw/library/decorators/IncreaseBooksCapacityDecorator.java

@@ -1,4 +1,6 @@
-package edu.uastw;
+package edu.uastw.library.decorators;
+
+import edu.uastw.library.Library;
 
 public class IncreaseBooksCapacityDecorator extends LibraryDecorator {
     private final int additionalCapacity;

src/main/java/edu/uastw/library/decorators/LibraryDecorator.java

@@ -1,4 +1,6 @@
-package edu.uastw;
+package edu.uastw.library.decorators;
+
+import edu.uastw.library.Library;
 
 public abstract class LibraryDecorator {
     protected Library library;

src/main/java/edu/uastw/library/items/Book.java

@@ -1,4 +1,4 @@
-package edu.uastw;
+package edu.uastw.library.items;
 
 public class Book implements LibraryItem {
     private final String title;

src/main/java/edu/uastw/library/items/ItemType.java

@@ -1,4 +1,4 @@
-package edu.uastw;
+package edu.uastw.library.items;
 
 public enum ItemType {
     BOOK,

src/main/java/edu/uastw/library/items/LibraryItem.java

@@ -1,4 +1,4 @@
-package edu.uastw;
+package edu.uastw.library.items;
 
 public interface LibraryItem {
     String getTitle();

src/main/java/edu/uastw/library/items/Magazine.java

@@ -1,4 +1,4 @@
-package edu.uastw;
+package edu.uastw.library.items;
 
 public class Magazine implements LibraryItem {
     private final String title;

src/test/java/LibraryTest.java

@@ -1,21 +1,34 @@
-import edu.uastw.Book;
-import edu.uastw.Library;
-import edu.uastw.LibraryItem;
+import edu.uastw.library.LibraryBuilder;
+import edu.uastw.library.decorators.DecreaseBooksCapacityDecorator;
+import edu.uastw.library.decorators.IncreaseBooksCapacityDecorator;
+import edu.uastw.library.decorators.LibraryDecorator;
+import edu.uastw.library.items.Book;
+import edu.uastw.library.Library;
+import edu.uastw.library.items.ItemType;
+import edu.uastw.library.items.LibraryItem;
+import edu.uastw.library.items.Magazine;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
 import java.lang.reflect.Field;
+import java.util.Iterator;
 import java.util.List;
 
 import static org.junit.Assert.*;
 
 public class LibraryTest {
+    private final ByteArrayOutputStream outputStreamCaptor = new ByteArrayOutputStream();
+    private static int LIBRARY_CAPACITY = 3;
     private Library library;
 
     @Before
     public void setUp() {
         library = Library.getInstance();
+        System.setOut(new PrintStream(outputStreamCaptor));
+        library.setBooksCapacity(LIBRARY_CAPACITY);
     }
 
     @After
@@ -25,10 +38,12 @@ public class LibraryTest {
         List<LibraryItem> libraryItems = (List<LibraryItem>) libraryItemsField.get(library);
         libraryItems.clear();
     }
+
     @Test
     public void testAddItem() {
         LibraryItem book = new Book("Test Book", "Test Author");
         library.addLibraryItem(book);
+
         assertTrue(library.iterator().hasNext());
     }
 
@@ -36,6 +51,7 @@ public class LibraryTest {
     public void testIterator() {
         LibraryItem book = new Book("Test Book", "Test Author");
         library.addLibraryItem(book);
+
         assertTrue(library.iterator().hasNext());
         assertEquals(book, library.iterator().next());
     }
@@ -52,4 +68,98 @@ public class LibraryTest {
 
         assertEquals(3, library.getBooksCapacity());
     }
+
+    @Test
+    public void testCapacityReached() {
+        LibraryItem book1 = new Book("Book 1", "Author 1");
+        LibraryItem book2 = new Book("Book 2", "Author 2");
+        LibraryItem book3 = new Book("Book 3", "Author 3");
+        LibraryItem book4 = new Book("Book 4", "Author 4");
+
+        library.addLibraryItem(book1);
+        library.addLibraryItem(book2);
+        library.addLibraryItem(book3);
+
+        outputStreamCaptor.reset();
+
+        library.addLibraryItem(book4);
+
+        assertEquals("Library capacity reached. Cannot add more items.\n", outputStreamCaptor.toString());
+    }
+
+    @Test
+    public void testCustomIterator() {
+        LibraryItem book1 = new Book("Book 1", "Author 1");
+        LibraryItem book2 = new Book("Book 2", "Author 2");
+        LibraryItem magazine = new Magazine("Magazine 1", "Publisher 1");
+
+        library.addLibraryItem(book1);
+        library.addLibraryItem(book2);
+        library.addLibraryItem(magazine);
+
+        Iterator<LibraryItem> bookIterator = library.customTypeIterator(ItemType.BOOK);
+
+        assertTrue(bookIterator.hasNext());
+        assertEquals("Book 1", bookIterator.next().getTitle());
+        assertTrue(bookIterator.hasNext());
+        assertEquals("Author 2", bookIterator.next().getOwner());
+        assertFalse(bookIterator.hasNext());
+    }
+
+    @Test
+    public void testIncreaseBooksCapacityDecorator() {
+        LibraryDecorator decorator = new IncreaseBooksCapacityDecorator(library, 2);
+        decorator.extendedFunctionality();
+
+        assertEquals(5, library.getBooksCapacity());
+    }
+
+    @Test
+    public void testDecreaseBooksCapacityDecorator() {
+        LibraryDecorator decorator = new DecreaseBooksCapacityDecorator(library, 2);
+        decorator.extendedFunctionality();
+
+        assertEquals(1, library.getBooksCapacity());
+    }
+
+    @Test
+    public void testDecreaseBooksCapacityDecoratorMax() {
+        library.setBooksCapacity(1);
+        LibraryDecorator decorator = new DecreaseBooksCapacityDecorator(library, 2);
+        decorator.extendedFunctionality();
+
+        assertEquals(1, library.getBooksCapacity());
+    }
+
+    @Test
+    public void testDisplayLibraryItems() {
+        LibraryItem book1 = new Book("Book 1", "Author 1");
+        LibraryItem book2 = new Book("Book 2", "Author 2");
+
+        library.addLibraryItem(book1);
+        library.addLibraryItem(book2);
+
+        outputStreamCaptor.reset();
+
+        library.displayLibraryItems();
+        String expectedOutput = "Items available in the library:\nBook 1 by Author 1\nBook 2 by Author 2\n";
+
+        assertEquals(expectedOutput, outputStreamCaptor.toString());
+    }
+
+    @Test
+    public void testBuilder() {
+        LibraryItem book1 = new Book("Book 1", "Author 1");
+        LibraryItem book2 = new Book("Book 2", "Author 2");
+        LibraryItem book3 = new Book("Book 3", "Author 3");
+
+        Library library = new LibraryBuilder()
+                .setBooksCapacity(3)
+                .addLibraryItem(book1)
+                .addLibraryItem(book2)
+                .addLibraryItem(book3)
+                .build();
+
+        assertEquals(3, library.getBooksCapacity());
+    }
 }