📍Use lombok, reformat, and optimize the code (#1560)

* Use lombok, reformat, and optimize the code

* Fix merge conflicts and some sonar issues

Co-authored-by: va1m <va1m@email.com>

fluentinterface/src/main/java/com/iluwatar/fluentinterface/app/App.java

@@ -30,8 +30,7 @@ import java.util.List;
 import java.util.StringJoiner;
 import java.util.function.Function;
 import java.util.function.Predicate;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import lombok.extern.slf4j.Slf4j;
 
 /**
  * The Fluent Interface pattern is useful when you want to provide an easy readable, flowing API.
@@ -44,10 +43,9 @@ import org.slf4j.LoggerFactory;
  * demonstrated with a simple number list that is filtered, transformed and collected. The result is
  * printed afterwards.
  */
+@Slf4j
 public class App {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
-
   /**
    * Program entry point.
    */

fluentinterface/src/main/java/com/iluwatar/fluentinterface/fluentiterable/lazy/LazyFluentIterable.java

@@ -30,6 +30,7 @@ import java.util.List;
 import java.util.Optional;
 import java.util.function.Function;
 import java.util.function.Predicate;
+import lombok.RequiredArgsConstructor;
 
 /**
  * This is a lazy implementation of the FluentIterable interface. It evaluates all chained
@@ -37,19 +38,11 @@ import java.util.function.Predicate;
  *
  * @param <E> the type of the objects the iteration is about
  */
+@RequiredArgsConstructor
 public class LazyFluentIterable<E> implements FluentIterable<E> {
 
   private final Iterable<E> iterable;
 
-  /**
-   * This constructor creates a new LazyFluentIterable. It wraps the given iterable.
-   *
-   * @param iterable the iterable this FluentIterable works on.
-   */
-  protected LazyFluentIterable(Iterable<E> iterable) {
-    this.iterable = iterable;
-  }
-
   /**
    * This constructor can be used to implement anonymous subclasses of the LazyFluentIterable.
    */

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

@@ -32,6 +32,7 @@ import java.util.Spliterator;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Predicate;
+import lombok.RequiredArgsConstructor;
 
 /**
  * This is a simple implementation of the FluentIterable interface. It evaluates all chained
@@ -39,19 +40,11 @@ import java.util.function.Predicate;
  *
  * @param <E> the type of the objects the iteration is about
  */
+@RequiredArgsConstructor
 public class SimpleFluentIterable<E> implements FluentIterable<E> {
 
   private final Iterable<E> iterable;
 
-  /**
-   * This constructor creates a copy of a given iterable's contents.
-   *
-   * @param iterable the iterable this interface copies to work on.
-   */
-  protected SimpleFluentIterable(Iterable<E> iterable) {
-    this.iterable = iterable;
-  }
-
   /**
    * Filters the contents of Iterable using the given predicate, leaving only the ones which satisfy
    * the predicate.

fluentinterface/src/test/java/com/iluwatar/fluentinterface/fluentiterable/FluentIterableTest.java

@@ -53,7 +53,7 @@ public abstract class FluentIterableTest {
   protected abstract FluentIterable<Integer> createFluentIterable(final Iterable<Integer> integers);
 
   @Test
-  public void testFirst() {
+  void testFirst() {
     final var integers = List.of(1, 2, 3, 10, 9, 8);
     final var first = createFluentIterable(integers).first();
     assertNotNull(first);
@@ -62,7 +62,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testFirstEmptyCollection() {
+  void testFirstEmptyCollection() {
     final var integers = Collections.<Integer>emptyList();
     final var first = createFluentIterable(integers).first();
     assertNotNull(first);
@@ -70,7 +70,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testFirstCount() {
+  void testFirstCount() {
     final var integers = List.of(1, 2, 3, 10, 9, 8);
     final var first4 = createFluentIterable(integers)
         .first(4)
@@ -86,7 +86,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testFirstCountLessItems() {
+  void testFirstCountLessItems() {
     final var integers = List.of(1, 2, 3);
     final var first4 = createFluentIterable(integers)
         .first(4)
@@ -101,7 +101,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testLast() {
+  void testLast() {
     final var integers = List.of(1, 2, 3, 10, 9, 8);
     final var last = createFluentIterable(integers).last();
     assertNotNull(last);
@@ -110,7 +110,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testLastEmptyCollection() {
+  void testLastEmptyCollection() {
     final var integers = Collections.<Integer>emptyList();
     final var last = createFluentIterable(integers).last();
     assertNotNull(last);
@@ -118,7 +118,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testLastCount() {
+  void testLastCount() {
     final var integers = List.of(1, 2, 3, 10, 9, 8);
     final var last4 = createFluentIterable(integers)
         .last(4)
@@ -133,7 +133,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testLastCountLessItems() {
+  void testLastCountLessItems() {
     final var integers = List.of(1, 2, 3);
     final var last4 = createFluentIterable(integers)
         .last(4)
@@ -148,7 +148,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testFilter() {
+  void testFilter() {
     final var integers = List.of(1, 2, 3, 10, 9, 8);
     final var evenItems = createFluentIterable(integers)
         .filter(i -> i % 2 == 0)
@@ -162,7 +162,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testMap() {
+  void testMap() {
     final var integers = List.of(1, 2, 3);
     final var longs = createFluentIterable(integers)
         .map(Integer::longValue)
@@ -176,7 +176,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testForEach() {
+  void testForEach() {
     final var integers = List.of(1, 2, 3);
 
     final Consumer<Integer> consumer = mock(Consumer.class);
@@ -190,7 +190,7 @@ public abstract class FluentIterableTest {
   }
 
   @Test
-  public void testSpliterator() throws Exception {
+  void testSpliterator() throws Exception {
     final var integers = List.of(1, 2, 3);
     final var split = createFluentIterable(integers).spliterator();
     assertNotNull(split);

fluentinterface/src/test/java/com/iluwatar/fluentinterface/fluentiterable/lazy/LazyFluentIterableTest.java

@@ -31,7 +31,7 @@ import com.iluwatar.fluentinterface.fluentiterable.FluentIterableTest;
  *
  * @author Jeroen Meulemeester
  */
-public class LazyFluentIterableTest extends FluentIterableTest {
+class LazyFluentIterableTest extends FluentIterableTest {
 
   @Override
   protected FluentIterable<Integer> createFluentIterable(Iterable<Integer> integers) {

fluentinterface/src/test/java/com/iluwatar/fluentinterface/fluentiterable/simple/SimpleFluentIterableTest.java

@@ -31,7 +31,7 @@ import com.iluwatar.fluentinterface.fluentiterable.FluentIterableTest;
  *
  * @author Jeroen Meulemeester
  */
-public class SimpleFluentIterableTest extends FluentIterableTest {
+class SimpleFluentIterableTest extends FluentIterableTest {
 
   @Override
   protected FluentIterable<Integer> createFluentIterable(Iterable<Integer> integers) {