Minor refactorings and code style changes. 1) Removed several use of …

…raw types 2) Removed unnecessary throws clauses 3) Used lambda expressions wherever applicable 4) Used apt assertion methods for readability 5) Use of try with resources wherever applicable 6) Corrected incorrect order of assertXXX arguments

fluentinterface/src/main/java/com/iluwatar/fluentinterface/fluentiterable/simple/SimpleFluentIterable.java

@@ -171,11 +171,11 @@ public List<E> asList() {
   /**
    * @return a FluentIterable from a given iterable. Calls the SimpleFluentIterable constructor.
    */
-  public static final <E> FluentIterable<E> from(Iterable<E> iterable) {
+  public static <E> FluentIterable<E> from(Iterable<E> iterable) {
     return new SimpleFluentIterable<>(iterable);
   }
 
-  public static final <E> FluentIterable<E> fromCopyOf(Iterable<E> iterable) {
+  public static <E> FluentIterable<E> fromCopyOf(Iterable<E> iterable) {
     List<E> copy = FluentIterable.copyToList(iterable);
     return new SimpleFluentIterable<>(copy);
   }

front-controller/src/main/java/com/iluwatar/front/controller/FrontController.java

@@ -36,16 +36,16 @@ public void handleRequest(String request) {
   }
 
   private Command getCommand(String request) {
-    Class commandClass = getCommandClass(request);
+    Class<?> commandClass = getCommandClass(request);
     try {
       return (Command) commandClass.newInstance();
     } catch (Exception e) {
       throw new ApplicationException(e);
     }
   }
 
-  private static Class getCommandClass(String request) {
-    Class result;
+  private static Class<?> getCommandClass(String request) {
+    Class<?> result;
     try {
       result = Class.forName("com.iluwatar.front.controller." + request + "Command");
     } catch (ClassNotFoundException e) {

front-controller/src/test/java/com/iluwatar/front/controller/ApplicationExceptionTest.java

@@ -34,7 +34,7 @@
 public class ApplicationExceptionTest {
 
   @Test
-  public void testCause() throws Exception {
+  public void testCause() {
     final Exception cause = new Exception();
     assertSame(cause, new ApplicationException(cause).getCause());
   }

guarded-suspension/src/test/java/com/iluwatar/guarded/suspension/GuardedQueueTest.java

@@ -41,7 +41,7 @@ public void testGet() {
     GuardedQueue g = new GuardedQueue();
     ExecutorService executorService = Executors.newFixedThreadPool(2);
     executorService.submit(() -> value = g.get());
-    executorService.submit(() -> g.put(Integer.valueOf(10)));
+    executorService.submit(() -> g.put(10));
     executorService.shutdown();
     try {
       executorService.awaitTermination(30, TimeUnit.SECONDS);

half-sync-half-async/src/test/java/com/iluwatar/halfsynchalfasync/AppTest.java

@@ -34,7 +34,7 @@
 public class AppTest {
 
   @Test
-  public void test() throws InterruptedException, ExecutionException {
+  public void test() {
     App.main(null);
   }
 }

half-sync-half-async/src/test/java/com/iluwatar/halfsynchalfasync/AsynchronousServiceTest.java

@@ -22,6 +22,7 @@
  */
 package com.iluwatar.halfsynchalfasync;
 
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.InOrder;
 
@@ -44,11 +45,17 @@
  * @author Jeroen Meulemeester
  */
 public class AsynchronousServiceTest {
+  private AsynchronousService service;
+  private AsyncTask<Object> task;
+
+  @BeforeEach
+  public void setUp() {
+    service = new AsynchronousService(new LinkedBlockingQueue<>());
+    task = mock(AsyncTask.class);
+  }
 
   @Test
   public void testPerfectExecution() throws Exception {
-    final AsynchronousService service = new AsynchronousService(new LinkedBlockingQueue<>());
-    final AsyncTask<Object> task = mock(AsyncTask.class);
     final Object result = new Object();
     when(task.call()).thenReturn(result);
     service.execute(task);
@@ -65,8 +72,6 @@ public void testPerfectExecution() throws Exception {
 
   @Test
   public void testCallException() throws Exception {
-    final AsynchronousService service = new AsynchronousService(new LinkedBlockingQueue<>());
-    final AsyncTask<Object> task = mock(AsyncTask.class);
     final IOException exception = new IOException();
     when(task.call()).thenThrow(exception);
     service.execute(task);
@@ -82,9 +87,7 @@ public void testCallException() throws Exception {
   }
 
   @Test
-  public void testPreCallException() throws Exception {
-    final AsynchronousService service = new AsynchronousService(new LinkedBlockingQueue<>());
-    final AsyncTask<Object> task = mock(AsyncTask.class);
+  public void testPreCallException() {
     final IllegalStateException exception = new IllegalStateException();
     doThrow(exception).when(task).onPreCall();
     service.execute(task);

intercepting-filter/src/main/java/com/iluwatar/intercepting/filter/Client.java

@@ -22,9 +22,6 @@
  */
 package com.iluwatar.intercepting.filter;
 
-import java.awt.BorderLayout;
-import java.awt.GridLayout;
-
 import javax.swing.JButton;
 import javax.swing.JFrame;
 import javax.swing.JLabel;
@@ -33,6 +30,9 @@
 import javax.swing.JTextArea;
 import javax.swing.JTextField;
 import javax.swing.SwingUtilities;
+import javax.swing.WindowConstants;
+import java.awt.BorderLayout;
+import java.awt.GridLayout;
 
 /**
  * The Client class is responsible for handling the input and running them through filters inside the
@@ -60,7 +60,7 @@ public class Client extends JFrame { // NOSONAR
    */
   public Client() {
     super("Client System");
-    setDefaultCloseOperation(EXIT_ON_CLOSE);
+    setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
     setSize(300, 300);
     jl = new JLabel("RUNNING...");
     jtFields = new JTextField[3];

intercepting-filter/src/main/java/com/iluwatar/intercepting/filter/Target.java

@@ -22,19 +22,19 @@
  */
 package com.iluwatar.intercepting.filter;
 
-import java.awt.BorderLayout;
-import java.awt.Dimension;
-import java.awt.event.ActionEvent;
-import java.awt.event.ActionListener;
-
 import javax.swing.JButton;
 import javax.swing.JFrame;
 import javax.swing.JPanel;
 import javax.swing.JRootPane;
 import javax.swing.JScrollPane;
 import javax.swing.JTable;
 import javax.swing.SwingUtilities;
+import javax.swing.WindowConstants;
 import javax.swing.table.DefaultTableModel;
+import java.awt.BorderLayout;
+import java.awt.Dimension;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
 
 /**
  * This is where the requests are displayed after being validated by filters.
@@ -47,7 +47,6 @@ public class Target extends JFrame { //NOSONAR
   private static final long serialVersionUID = 1L;
 
   private JTable jt;
-  private JScrollPane jsp;
   private DefaultTableModel dtm;
   private JButton del;
 
@@ -56,7 +55,7 @@ public class Target extends JFrame { //NOSONAR
    */
   public Target() {
     super("Order System");
-    setDefaultCloseOperation(EXIT_ON_CLOSE);
+    setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
     setSize(640, 480);
     dtm =
         new DefaultTableModel(new Object[] {"Name", "Contact Number", "Address", "Deposit Number",
@@ -73,7 +72,7 @@ private void setup() {
     bot.setLayout(new BorderLayout());
     bot.add(del, BorderLayout.EAST);
     add(bot, BorderLayout.SOUTH);
-    jsp = new JScrollPane(jt);
+    JScrollPane jsp = new JScrollPane(jt);
     jsp.setPreferredSize(new Dimension(500, 250));
     add(jsp, BorderLayout.CENTER);
 

intercepting-filter/src/test/java/com/iluwatar/intercepting/filter/FilterManagerTest.java

@@ -40,15 +40,15 @@
 public class FilterManagerTest {
 
   @Test
-  public void testFilterRequest() throws Exception {
+  public void testFilterRequest() {
     final Target target = mock(Target.class);
     final FilterManager filterManager = new FilterManager();
     assertEquals("RUNNING...", filterManager.filterRequest(mock(Order.class)));
     verifyZeroInteractions(target);
   }
 
   @Test
-  public void testAddFilter() throws Exception {
+  public void testAddFilter() {
     final Target target = mock(Target.class);
     final FilterManager filterManager = new FilterManager();
 

intercepting-filter/src/test/java/com/iluwatar/intercepting/filter/FilterTest.java

@@ -89,15 +89,15 @@ static List<Object[]> getTestData() {
 
   @ParameterizedTest
   @MethodSource("getTestData")
-  public void testExecute(Filter filter, Order order, String expectedResult) throws Exception {
+  public void testExecute(Filter filter, Order order, String expectedResult) {
     final String result = filter.execute(order);
     assertNotNull(result);
     assertEquals(expectedResult, result.trim());
   }
 
   @ParameterizedTest
   @MethodSource("getTestData")
-  public void testNext(Filter filter) throws Exception {
+  public void testNext(Filter filter) {
     assertNull(filter.getNext());
     assertSame(filter, filter.getLast());
   }

intercepting-filter/src/test/java/com/iluwatar/intercepting/filter/OrderTest.java

@@ -36,35 +36,35 @@ public class OrderTest {
   private static final String EXPECTED_VALUE = "test";
 
   @Test
-  public void testSetName() throws Exception {
+  public void testSetName() {
     final Order order = new Order();
     order.setName(EXPECTED_VALUE);
     assertEquals(EXPECTED_VALUE, order.getName());
   }
 
   @Test
-  public void testSetContactNumber() throws Exception {
+  public void testSetContactNumber() {
     final Order order = new Order();
     order.setContactNumber(EXPECTED_VALUE);
     assertEquals(EXPECTED_VALUE, order.getContactNumber());
   }
 
   @Test
-  public void testSetAddress() throws Exception {
+  public void testSetAddress() {
     final Order order = new Order();
     order.setAddress(EXPECTED_VALUE);
     assertEquals(EXPECTED_VALUE, order.getAddress());
   }
 
   @Test
-  public void testSetDepositNumber() throws Exception {
+  public void testSetDepositNumber() {
     final Order order = new Order();
     order.setDepositNumber(EXPECTED_VALUE);
     assertEquals(EXPECTED_VALUE, order.getDepositNumber());
   }
 
   @Test
-  public void testSetOrder() throws Exception {
+  public void testSetOrder() {
     final Order order = new Order();
     order.setOrderItem(EXPECTED_VALUE);
     assertEquals(EXPECTED_VALUE, order.getOrderItem());

iterator/src/test/java/com/iluwatar/iterator/bst/BstIteratorTest.java

@@ -50,49 +50,49 @@ void createTrees() {
 
   @Test
   void nextForEmptyTree() {
-    BstIterator iter = new BstIterator<>(emptyRoot);
+    BstIterator<Integer> iter = new BstIterator<>(emptyRoot);
     assertThrows(NoSuchElementException.class, iter::next,
         "next() should throw an IllegalStateException if hasNext() is false.");
   }
 
   @Test
   void nextOverEntirePopulatedTree() {
-    BstIterator iter = new BstIterator<>(nonEmptyRoot);
-    assertEquals(1, iter.next().getVal(), "First Node is 1.");
-    assertEquals(3, iter.next().getVal(), "Second Node is 3.");
-    assertEquals(4, iter.next().getVal(), "Third Node is 4.");
-    assertEquals(5, iter.next().getVal(), "Fourth Node is 5.");
-    assertEquals(6, iter.next().getVal(), "Fifth Node is 6.");
-    assertEquals(7, iter.next().getVal(), "Sixth Node is 7.");
+    BstIterator<Integer> iter = new BstIterator<>(nonEmptyRoot);
+    assertEquals(Integer.valueOf(1), iter.next().getVal(), "First Node is 1.");
+    assertEquals(Integer.valueOf(3), iter.next().getVal(), "Second Node is 3.");
+    assertEquals(Integer.valueOf(4), iter.next().getVal(), "Third Node is 4.");
+    assertEquals(Integer.valueOf(5), iter.next().getVal(), "Fourth Node is 5.");
+    assertEquals(Integer.valueOf(6), iter.next().getVal(), "Fifth Node is 6.");
+    assertEquals(Integer.valueOf(7), iter.next().getVal(), "Sixth Node is 7.");
   }
 
   @Test
   void hasNextForEmptyTree() {
-    BstIterator iter = new BstIterator<>(emptyRoot);
+    BstIterator<Integer> iter = new BstIterator<>(emptyRoot);
     assertFalse(iter.hasNext(), "hasNext() should return false for empty tree.");
   }
 
   @Test
   void hasNextForPopulatedTree() {
-    BstIterator iter = new BstIterator<>(nonEmptyRoot);
+    BstIterator<Integer> iter = new BstIterator<>(nonEmptyRoot);
     assertTrue(iter.hasNext(), "hasNext() should return true for populated tree.");
   }
 
   @Test
   void nextAndHasNextOverEntirePopulatedTree() {
-    BstIterator iter = new BstIterator<>(nonEmptyRoot);
+    BstIterator<Integer> iter = new BstIterator<>(nonEmptyRoot);
     assertTrue(iter.hasNext(), "Iterator hasNext() should be true.");
-    assertEquals(1, iter.next().getVal(), "First Node is 1.");
+    assertEquals(Integer.valueOf(1), iter.next().getVal(), "First Node is 1.");
     assertTrue(iter.hasNext(), "Iterator hasNext() should be true.");
-    assertEquals(3, iter.next().getVal(), "Second Node is 3.");
+    assertEquals(Integer.valueOf(3), iter.next().getVal(), "Second Node is 3.");
     assertTrue(iter.hasNext(), "Iterator hasNext() should be true.");
-    assertEquals(4, iter.next().getVal(), "Third Node is 4.");
+    assertEquals(Integer.valueOf(4), iter.next().getVal(), "Third Node is 4.");
     assertTrue(iter.hasNext(), "Iterator hasNext() should be true.");
-    assertEquals(5, iter.next().getVal(), "Fourth Node is 5.");
+    assertEquals(Integer.valueOf(5), iter.next().getVal(), "Fourth Node is 5.");
     assertTrue(iter.hasNext(), "Iterator hasNext() should be true.");
-    assertEquals(6, iter.next().getVal(), "Fifth Node is 6.");
+    assertEquals(Integer.valueOf(6), iter.next().getVal(), "Fifth Node is 6.");
     assertTrue(iter.hasNext(), "Iterator hasNext() should be true.");
-    assertEquals(7, iter.next().getVal(), "Sixth Node is 7.");
+    assertEquals(Integer.valueOf(7), iter.next().getVal(), "Sixth Node is 7.");
     assertFalse(iter.hasNext(), "Iterator hasNext() should be false, end of tree.");
   }
 

layers/src/main/java/com/iluwatar/layers/CakeViewImpl.java

@@ -41,6 +41,6 @@ public CakeViewImpl(CakeBakingService cakeBakingService) {
   }
 
   public void render() {
-    cakeBakingService.getAllCakes().stream().forEach(cake -> LOGGER.info(cake.toString()));
+    cakeBakingService.getAllCakes().forEach(cake -> LOGGER.info(cake.toString()));
   }
 }

layers/src/test/java/com/iluwatar/layers/CakeBakingExceptionTest.java

@@ -35,14 +35,14 @@
 public class CakeBakingExceptionTest {
 
   @Test
-  public void testConstructor() throws Exception {
+  public void testConstructor() {
     final CakeBakingException exception = new CakeBakingException();
     assertNull(exception.getMessage());
     assertNull(exception.getCause());
   }
 
   @Test
-  public void testConstructorWithMessage() throws Exception {
+  public void testConstructorWithMessage() {
     final String expectedMessage = "message";
     final CakeBakingException exception = new CakeBakingException(expectedMessage);
     assertEquals(expectedMessage, exception.getMessage());

layers/src/test/java/com/iluwatar/layers/CakeBakingServiceImplTest.java

@@ -42,7 +42,7 @@
 public class CakeBakingServiceImplTest {
 
   @Test
-  public void testLayers() throws CakeBakingException {
+  public void testLayers() {
     final CakeBakingServiceImpl service = new CakeBakingServiceImpl();
 
     final List<CakeLayerInfo> initialLayers = service.getAvailableLayers();
@@ -65,7 +65,7 @@ public void testLayers() throws CakeBakingException {
   }
 
   @Test
-  public void testToppings() throws CakeBakingException {
+  public void testToppings() {
     final CakeBakingServiceImpl service = new CakeBakingServiceImpl();
 
     final List<CakeToppingInfo> initialToppings = service.getAvailableToppings();
@@ -125,7 +125,7 @@ public void testBakeCakes() throws CakeBakingException {
   }
 
   @Test
-  public void testBakeCakeMissingTopping() throws CakeBakingException {
+  public void testBakeCakeMissingTopping() {
     final CakeBakingServiceImpl service = new CakeBakingServiceImpl();
 
     final CakeLayerInfo layer1 = new CakeLayerInfo("Layer1", 1000);
@@ -140,7 +140,7 @@ public void testBakeCakeMissingTopping() throws CakeBakingException {
   }
 
   @Test
-  public void testBakeCakeMissingLayer() throws CakeBakingException {
+  public void testBakeCakeMissingLayer() {
     final CakeBakingServiceImpl service = new CakeBakingServiceImpl();
 
     final List<CakeInfo> initialCakes = service.getAllCakes();