diff --git a/core-java-8/pom.xml b/core-java-8/pom.xml
index 0e589ebf47..f99d85f564 100644
--- a/core-java-8/pom.xml
+++ b/core-java-8/pom.xml
@@ -41,6 +41,12 @@
             <version>3.3.2</version>
         </dependency>
 
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-api</artifactId>
+            <version>${org.slf4j.version}</version>
+        </dependency>
+
         <!-- test scoped -->
 
         <dependency>
diff --git a/core-java-8/src/test/java/com/baeldung/java8/Java8StreamApiTest.java b/core-java-8/src/test/java/com/baeldung/java8/Java8StreamApiTest.java
index a436b3e93f..37326c6d26 100644
--- a/core-java-8/src/test/java/com/baeldung/java8/Java8StreamApiTest.java
+++ b/core-java-8/src/test/java/com/baeldung/java8/Java8StreamApiTest.java
@@ -2,44 +2,35 @@ package com.baeldung.java8;
 
 import com.baeldung.streamApi.Product;
 import org.junit.Before;
-import org.junit.BeforeClass;
 import org.junit.Test;
-import org.mockito.Mock;
-import org.mockito.Mockito;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.BufferedWriter;
-import java.io.File;
 import java.io.IOException;
 import java.nio.charset.Charset;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.nio.file.Paths;
 import java.util.*;
-import java.util.logging.Logger;
 import java.util.regex.Pattern;
 import java.util.stream.*;
 
 import static org.junit.Assert.*;
-import static org.mockito.Matchers.anyString;
-import static org.mockito.Mockito.mock;
 
-/**
- * Created by Alex Vengr
- */
 public class Java8StreamApiTest {
 
     private long counter;
 
-    private static Logger log = Logger.getAnonymousLogger();
+    private static Logger log = LoggerFactory.getLogger(Java8StreamApiTest.class);
 
     private List<Product> productList;
 
-
     @Before
     public void init() {
-        productList = Arrays.asList(new Product(23, "potatoes"),
-          new Product(14, "orange"), new Product(13, "lemon"),
-            new Product(23, "bread"), new Product(13, "sugar"));
+        productList = Arrays.asList(
+                new Product(23, "potatoes"), new Product(14, "orange"),
+                new Product(13, "lemon"), new Product(23, "bread"),
+                new Product(13, "sugar"));
     }
 
     @Test
@@ -47,7 +38,7 @@ public class Java8StreamApiTest {
 
         List<String> list = Arrays.asList("abc1", "abc2", "abc3");
         long size = list.stream().skip(1)
-          .map(element -> element.substring(0, 3)).count();
+                .map(element -> element.substring(0, 3)).count();
         assertEquals(list.size() - 1, size);
     }
 
@@ -58,18 +49,18 @@ public class Java8StreamApiTest {
 
         counter = 0;
         long sizeFirst = list.stream()
-          .skip(2).map(element -> {
-              wasCalled();
-              return element.substring(0, 3);
-          }).count();
-        assertEquals( 1, counter);
+                .skip(2).map(element -> {
+                    wasCalled();
+                    return element.substring(0, 3);
+                }).count();
+        assertEquals(1, counter);
 
         counter = 0;
         long sizeSecond = list.stream().map(element -> {
             wasCalled();
             return element.substring(0, 3);
         }).skip(2).count();
-        assertEquals( 3, counter);
+        assertEquals(3, counter);
     }
 
     @Test
@@ -117,7 +108,7 @@ public class Java8StreamApiTest {
         try {
             streamOfStrings = Files.lines(path, Charset.forName("UTF-8"));
         } catch (IOException e) {
-            e.printStackTrace();
+            log.error("Error creating streams from paths {}", path, e.getMessage(), e);
         }
         assertEquals("a", streamOfStrings.findFirst().get());
 
@@ -136,13 +127,13 @@ public class Java8StreamApiTest {
 
         List<String> list = Arrays.asList("abc1", "abc2", "abc3");
         Optional<String> stream = list.stream()
-          .filter(element -> {
-              log.info("filter() was called");
-              return element.contains("2");
-          }).map(element -> {
-              log.info("map() was called");
-              return element.toUpperCase();
-          }).findFirst();
+                .filter(element -> {
+                    log.info("filter() was called");
+                    return element.contains("2");
+                }).map(element -> {
+                    log.info("map() was called");
+                    return element.toUpperCase();
+                }).findFirst();
     }
 
     @Test
@@ -155,17 +146,17 @@ public class Java8StreamApiTest {
         assertEquals(16, reducedTwoParams);
 
         int reducedThreeParams = Stream.of(1, 2, 3)
-          .reduce(10, (a, b) -> a + b, (a, b) -> {
-              log.info("combiner was called");
-              return a + b;
-          });
+                .reduce(10, (a, b) -> a + b, (a, b) -> {
+                    log.info("combiner was called");
+                    return a + b;
+                });
         assertEquals(16, reducedThreeParams);
 
         int reducedThreeParamsParallel = Arrays.asList(1, 2, 3).parallelStream()
-          .reduce(10, (a, b) -> a + b, (a, b) -> {
-              log.info("combiner was called");
-              return a + b;
-          });
+                .reduce(10, (a, b) -> a + b, (a, b) -> {
+                    log.info("combiner was called");
+                    return a + b;
+                });
         assertEquals(36, reducedThreeParamsParallel);
     }
 
@@ -173,13 +164,13 @@ public class Java8StreamApiTest {
     public void collecting_whenAsExpected_thenCorrect() {
 
         List<String> collectorCollection = productList.stream()
-          .map(Product::getName).collect(Collectors.toList());
+                .map(Product::getName).collect(Collectors.toList());
 
         assertTrue(collectorCollection instanceof List);
         assertEquals(5, collectorCollection.size());
 
         String listToString = productList.stream().map(Product::getName)
-          .collect(Collectors.joining(", ", "[", "]"));
+                .collect(Collectors.joining(", ", "[", "]"));
 
         assertTrue(listToString.contains(",") && listToString.contains("[") && listToString.contains("]"));
 
@@ -190,15 +181,15 @@ public class Java8StreamApiTest {
         assertEquals(86, summingPrice);
 
         IntSummaryStatistics statistics = productList.stream()
-          .collect(Collectors.summarizingInt(Product::getPrice));
+                .collect(Collectors.summarizingInt(Product::getPrice));
         assertEquals(23, statistics.getMax());
 
         Map<Integer, List<Product>> collectorMapOfLists = productList.stream()
-          .collect(Collectors.groupingBy(Product::getPrice));
+                .collect(Collectors.groupingBy(Product::getPrice));
         assertEquals(3, collectorMapOfLists.keySet().size());
 
         Map<Boolean, List<Product>> mapPartioned = productList.stream()
-          .collect(Collectors.partitioningBy(element -> element.getPrice() > 15));
+                .collect(Collectors.partitioningBy(element -> element.getPrice() > 15));
         assertEquals(2, mapPartioned.keySet().size());
 
     }
@@ -206,16 +197,19 @@ public class Java8StreamApiTest {
     @Test(expected = UnsupportedOperationException.class)
     public void collect_whenThrows_thenCorrect() {
         Set<Product> unmodifiableSet = productList.stream()
-          .collect(Collectors.collectingAndThen(Collectors.toSet(),
-            Collections::unmodifiableSet));
+                .collect(Collectors.collectingAndThen(Collectors.toSet(),
+                        Collections::unmodifiableSet));
         unmodifiableSet.add(new Product(4, "tea"));
     }
 
     @Test
     public void customCollector_whenResultContainsAllElementsFrSource_thenCorrect() {
         Collector<Product, ?, LinkedList<Product>> toLinkedList =
-          Collector.of(LinkedList::new, LinkedList::add,
-            (first, second) -> { first.addAll(second); return first; });
+                Collector.of(LinkedList::new, LinkedList::add,
+                        (first, second) -> {
+                            first.addAll(second);
+                            return first;
+                        });
 
         LinkedList<Product> linkedListOfPersons = productList.stream().collect(toLinkedList);
         assertTrue(linkedListOfPersons.containsAll(productList));
@@ -226,14 +220,14 @@ public class Java8StreamApiTest {
         Stream<Product> streamOfCollection = productList.parallelStream();
         boolean isParallel = streamOfCollection.isParallel();
         boolean haveBigPrice = streamOfCollection.map(product -> product.getPrice() * 12)
-          .anyMatch(price -> price > 200);
+                .anyMatch(price -> price > 200);
         assertTrue(isParallel && haveBigPrice);
     }
 
     @Test
     public void parallel_whenIsParallel_thenCorrect() {
         IntStream intStreamParallel =
-          IntStream.range(1, 150).parallel().map(element -> element * 34);
+                IntStream.range(1, 150).parallel().map(element -> element * 34);
         boolean isParallel = intStreamParallel.isParallel();
         assertTrue(isParallel);
     }
@@ -241,7 +235,7 @@ public class Java8StreamApiTest {
     @Test
     public void parallel_whenIsSequential_thenCorrect() {
         IntStream intStreamParallel =
-          IntStream.range(1, 150).parallel().map(element -> element * 34);
+                IntStream.range(1, 150).parallel().map(element -> element * 34);
         IntStream intStreamSequential = intStreamParallel.sequential();
         boolean isParallel = intStreamParallel.isParallel();
         assertFalse(isParallel);
@@ -252,13 +246,13 @@ public class Java8StreamApiTest {
         try {
             path = Files.createTempFile(null, ".txt");
         } catch (IOException e) {
-            e.printStackTrace();
+            log.error(e.getMessage());
         }
 
         try (BufferedWriter writer = Files.newBufferedWriter(path)) {
             writer.write("a\nb\nc");
         } catch (IOException e) {
-            e.printStackTrace();
+            log.error(e.getMessage());
         }
         return path;
     }