Merge origin/BAEL-2565 into BAEL-2565

core-java-8/README.md

@@ -15,7 +15,6 @@
 - [Guide to Java 8 Comparator.comparing()](http://www.baeldung.com/java-8-comparator-comparing)
 - [Guide To Java 8 Optional](http://www.baeldung.com/java-optional)
 - [Guide to the Java 8 forEach](http://www.baeldung.com/foreach-java)
-- [Java Base64 Encoding and Decoding](http://www.baeldung.com/java-base64-encode-and-decode)
 - [The Difference Between map() and flatMap()](http://www.baeldung.com/java-difference-map-and-flatmap)
 - [Static and Default Methods in Interfaces in Java](http://www.baeldung.com/java-static-default-methods)
 - [Efficient Word Frequency Calculator in Java](http://www.baeldung.com/java-word-frequency)
@@ -34,3 +33,8 @@
 - [Java Primitives versus Objects](https://www.baeldung.com/java-primitives-vs-objects)
 - [How to Use if/else Logic in Java 8 Streams](https://www.baeldung.com/java-8-streams-if-else-logic)
 - [How to Replace Many if Statements in Java](https://www.baeldung.com/java-replace-if-statements)
+- [Java @Override Annotation](https://www.baeldung.com/java-override)
+- [Java @SuppressWarnings Annotation](https://www.baeldung.com/java-suppresswarnings)
+- [Java @SafeVarargs Annotation](https://www.baeldung.com/java-safevarargs)
+- [Java @Deprecated Annotation](https://www.baeldung.com/java-deprecated)
+- [Java 8 Predicate Chain](https://www.baeldung.com/java-predicate-chain)

core-java-8/pom.xml

@@ -1,5 +1,5 @@
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-8</artifactId>
@@ -104,6 +104,24 @@
             <artifactId>aspectjweaver</artifactId>
             <version>${asspectj.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.powermock</groupId>
+            <artifactId>powermock-module-junit4</artifactId>
+            <version>${powermock.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.powermock</groupId>
+            <artifactId>powermock-api-mockito2</artifactId>
+            <version>${powermock.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.jmockit</groupId>
+            <artifactId>jmockit</artifactId>
+            <version>${jmockit.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
@@ -119,7 +137,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.1</version>
+                <version>${maven-compiler-plugin.version}</version>
                 <configuration>
                     <source>1.8</source>
                     <target>1.8</target>
@@ -142,6 +160,16 @@
                     </execution>
                 </executions>
             </plugin>
+            <plugin>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <version>${maven-surefire-plugin.version}</version>
+                <configuration>
+                    <argLine>
+                        -javaagent:${settings.localRepository}/org/jmockit/jmockit/${jmockit.version}/jmockit-${jmockit.version}.jar
+                    </argLine>
+                    <disableXmlReport>true</disableXmlReport>
+                </configuration>
+            </plugin>
         </plugins>
     </build>
 
@@ -159,9 +187,14 @@
         <!-- testing -->
         <assertj.version>3.6.1</assertj.version>
         <asspectj.version>1.8.9</asspectj.version>
+        <powermock.version>2.0.0-RC.4</powermock.version>
+        <jmockit.version>1.44</jmockit.version>
         <avaitility.version>1.7.0</avaitility.version>
         <jmh-core.version>1.19</jmh-core.version>
         <jmh-generator.version>1.19</jmh-generator.version>
         <spring-boot-maven-plugin.version>2.0.4.RELEASE</spring-boot-maven-plugin.version>
+        <!-- plugins -->
+        <maven-compiler-plugin.version>3.8.0</maven-compiler-plugin.version>
+        <maven-surefire-plugin.version>2.22.1</maven-surefire-plugin.version>
     </properties>
 </project>

core-java-8/src/main/java/com/baeldung/list/Flower.java

@@ -1,28 +0,0 @@
-package com.baeldung.list;
-
-public class Flower {
-
-    private String name;
-    private int petals;
-
-    public Flower(String name, int petals) {
-        this.name = name;
-        this.petals = petals;
-    }
-
-    public String getName() {
-        return name;
-    }
-
-    public void setName(String name) {
-        this.name = name;
-    }
-
-    public int getPetals() {
-        return petals;
-    }
-
-    public void setPetals(int petals) {
-        this.petals = petals;
-    }
-}

core-java-8/src/test/java/com/baeldung/java8/Java8CollectionCleanupUnitTest.java

@@ -1,49 +0,0 @@
-package com.baeldung.java8;
-
-import com.google.common.collect.Lists;
-import org.junit.Test;
-
-import java.util.List;
-import java.util.Objects;
-import java.util.stream.Collectors;
-
-import static org.hamcrest.Matchers.hasSize;
-import static org.junit.Assert.assertThat;
-
-public class Java8CollectionCleanupUnitTest {
-
-    // tests -
-
-    @Test
-    public void givenListContainsNulls_whenFilteringParallel_thenCorrect() {
-        final List<Integer> list = Lists.newArrayList(null, 1, 2, null, 3, null);
-        final List<Integer> listWithoutNulls = list.parallelStream().filter(Objects::nonNull).collect(Collectors.toList());
-
-        assertThat(listWithoutNulls, hasSize(3));
-    }
-
-    @Test
-    public void givenListContainsNulls_whenFilteringSerial_thenCorrect() {
-        final List<Integer> list = Lists.newArrayList(null, 1, 2, null, 3, null);
-        final List<Integer> listWithoutNulls = list.stream().filter(Objects::nonNull).collect(Collectors.toList());
-
-        assertThat(listWithoutNulls, hasSize(3));
-    }
-
-    @Test
-    public void givenListContainsNulls_whenRemovingNullsWithRemoveIf_thenCorrect() {
-        final List<Integer> listWithoutNulls = Lists.newArrayList(null, 1, 2, null, 3, null);
-        listWithoutNulls.removeIf(Objects::isNull);
-
-        assertThat(listWithoutNulls, hasSize(3));
-    }
-
-    @Test
-    public void givenListContainsDuplicates_whenRemovingDuplicatesWithJava8_thenCorrect() {
-        final List<Integer> listWithDuplicates = Lists.newArrayList(1, 1, 2, 2, 3, 3);
-        final List<Integer> listWithoutDuplicates = listWithDuplicates.parallelStream().distinct().collect(Collectors.toList());
-
-        assertThat(listWithoutDuplicates, hasSize(3));
-    }
-
-}

core-java-8/src/test/java/com/baeldung/java8/Java8PredicateChainUnitTest.java

@@ -0,0 +1,131 @@
+package com.baeldung.java8;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.contains;
+import static org.junit.Assert.assertEquals;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.Predicate;
+import java.util.stream.Collectors;
+
+import org.junit.Test;
+
+public class Java8PredicateChainUnitTest {
+    
+    private List<String> names = Arrays.asList("Adam", "Alexander", "John", "Tom");
+
+    @Test
+    public void whenFilterList_thenSuccess() {
+        List<String> result = names.stream()
+            .filter(name -> name.startsWith("A"))
+            .collect(Collectors.toList());
+
+        assertEquals(2, result.size());
+        assertThat(result, contains("Adam", "Alexander"));
+    }
+
+    @Test
+    public void whenFilterListWithMultipleFilters_thenSuccess() {
+        List<String> result = names.stream()
+            .filter(name -> name.startsWith("A"))
+            .filter(name -> name.length() < 5)
+            .collect(Collectors.toList());
+        
+        assertEquals(1, result.size());
+        assertThat(result, contains("Adam"));
+    }
+
+    @Test
+    public void whenFilterListWithComplexPredicate_thenSuccess() {
+        List<String> result = names.stream()
+            .filter(name -> name.startsWith("A") && name.length() < 5)
+            .collect(Collectors.toList());
+        
+        assertEquals(1, result.size());
+        assertThat(result, contains("Adam"));
+    }
+
+    @Test
+    public void whenFilterListWithCombinedPredicatesInline_thenSuccess() {
+        List<String> result = names.stream()
+            .filter(((Predicate<String>) name -> name.startsWith("A")).and(name -> name.length() < 5))
+            .collect(Collectors.toList());
+        
+        assertEquals(1, result.size());
+        assertThat(result, contains("Adam"));
+    }
+
+    @Test
+    public void whenFilterListWithCombinedPredicatesUsingAnd_thenSuccess() {
+        Predicate<String> predicate1 = str -> str.startsWith("A");
+        Predicate<String> predicate2 = str -> str.length() < 5;
+
+        List<String> result = names.stream()
+            .filter(predicate1.and(predicate2))
+            .collect(Collectors.toList());
+
+        assertEquals(1, result.size());
+        assertThat(result, contains("Adam"));
+    }
+
+    @Test
+    public void whenFilterListWithCombinedPredicatesUsingOr_thenSuccess() {
+        Predicate<String> predicate1 = str -> str.startsWith("J");
+        Predicate<String> predicate2 = str -> str.length() < 4;
+
+        List<String> result = names.stream()
+            .filter(predicate1.or(predicate2))
+            .collect(Collectors.toList());
+
+        assertEquals(2, result.size());
+        assertThat(result, contains("John", "Tom"));
+    }
+
+    @Test
+    public void whenFilterListWithCombinedPredicatesUsingOrAndNegate_thenSuccess() {
+        Predicate<String> predicate1 = str -> str.startsWith("J");
+        Predicate<String> predicate2 = str -> str.length() < 4;
+
+        List<String> result = names.stream()
+            .filter(predicate1.or(predicate2.negate()))
+            .collect(Collectors.toList());
+
+        assertEquals(3, result.size());
+        assertThat(result, contains("Adam", "Alexander", "John"));
+    }
+
+    @Test
+    public void whenFilterListWithCollectionOfPredicatesUsingAnd_thenSuccess() {
+        List<Predicate<String>> allPredicates = new ArrayList<Predicate<String>>();
+        allPredicates.add(str -> str.startsWith("A"));
+        allPredicates.add(str -> str.contains("d"));
+        allPredicates.add(str -> str.length() > 4);
+
+        List<String> result = names.stream()
+            .filter(allPredicates.stream()
+                .reduce(x -> true, Predicate::and))
+            .collect(Collectors.toList());
+
+        assertEquals(1, result.size());
+        assertThat(result, contains("Alexander"));
+    }
+
+    @Test
+    public void whenFilterListWithCollectionOfPredicatesUsingOr_thenSuccess() {
+        List<Predicate<String>> allPredicates = new ArrayList<Predicate<String>>();
+        allPredicates.add(str -> str.startsWith("A"));
+        allPredicates.add(str -> str.contains("d"));
+        allPredicates.add(str -> str.length() > 4);
+
+        List<String> result = names.stream()
+            .filter(allPredicates.stream()
+                .reduce(x -> false, Predicate::or))
+            .collect(Collectors.toList());
+
+        assertEquals(2, result.size());
+        assertThat(result, contains("Adam", "Alexander"));
+    }
+
+}

core-java-8/src/test/java/com/baeldung/list/AddElementsUnitTest.java

@@ -1,87 +0,0 @@
-package com.baeldung.list;
-
-import org.junit.Assert;
-import org.junit.Before;
-import org.junit.Test;
-
-import java.util.*;
-
-import static org.junit.Assert.*;
-
-public class AddElementsUnitTest {
-
-    List<Flower> flowers;
-
-    @Before
-    public void init() {
-        this.flowers = new ArrayList<>(Arrays.asList(
-                new Flower("Poppy", 12),
-                new Flower("Anemone", 8),
-                new Flower("Catmint", 12)));
-    }
-
-    @Test
-    public void givenAList_whenTargetListIsEmpty_thenReturnTargetListWithNewItems() {
-        List<Flower> anotherList = new ArrayList<>();
-        anotherList.addAll(flowers);
-
-        assertEquals(anotherList.size(), flowers.size());
-        Assert.assertTrue(anotherList.containsAll(flowers));
-    }
-
-    @Test
-    public void givenAList_whenTargetListIsEmpty_thenReturnTargetListWithOneModifiedElementByConstructor() {
-        List<Flower> anotherList = new ArrayList<>();
-        anotherList.addAll(flowers);
-
-        Flower flower = anotherList.get(0);
-        flower.setPetals(flowers.get(0).getPetals() * 3);
-
-        assertEquals(anotherList.size(), flowers.size());
-        Assert.assertTrue(anotherList.containsAll(flowers));
-    }
-
-    @Test
-    public void givenAListAndElements_whenUseCollectionsAddAll_thenAddElementsToTargetList() {
-        List<Flower> target = new ArrayList<>();
-
-        Collections.addAll(target, flowers.get(0), flowers.get(1), flowers.get(2), flowers.get(0));
-
-        assertEquals(target.size(), 4);
-    }
-
-    @Test
-    public void givenTwoList_whenSourceListDoesNotHaveNullElements_thenAddElementsToTargetListSkipFirstElementByStreamProcess() {
-        List<Flower> flowerVase = new ArrayList<>();
-
-        flowers.stream()
-                .skip(1)
-                .forEachOrdered(flowerVase::add);
-
-        assertEquals(flowerVase.size() + 1, flowers.size());
-        assertFalse(flowerVase.containsAll(flowers));
-    }
-
-    @Test
-    public void givenTwoList_whenSourceListDoesNotHaveNullElements_thenAddElementsToTargetListFilteringElementsByStreamProcess() {
-        List<Flower> flowerVase = new ArrayList<>();
-
-        flowers.stream()
-                .filter(f -> f.getPetals() > 10)
-                .forEachOrdered(flowerVase::add);
-
-        assertEquals(flowerVase.size() + 1, flowers.size());
-        assertFalse(flowerVase.containsAll(flowers));
-    }
-
-    @Test
-    public void givenAList_whenListIsNotNull_thenAddElementsToListByStreamProcessWihtOptional() {
-        List<Flower> target = new ArrayList<>();
-
-        Optional.ofNullable(flowers)
-                .ifPresent(target::addAll);
-
-        assertNotNull(target);
-        assertEquals(target.size(), 3);
-    }
-}

core-java-8/src/test/java/com/baeldung/time/LocalDateTimeUnitTest.java

@@ -0,0 +1,43 @@
+package com.baeldung.time;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.powermock.modules.junit4.PowerMockRunner;
+
+import java.time.Clock;
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.when;
+import static org.powermock.api.mockito.PowerMockito.mockStatic;
+
+@RunWith(PowerMockRunner.class)
+@PrepareForTest({ LocalDateTime.class })
+public class LocalDateTimeUnitTest {
+
+    @Test
+    public void givenLocalDateTimeMock_whenNow_thenGetFixedLocalDateTime() {
+        Clock clock = Clock.fixed(Instant.parse("2014-12-22T10:15:30.00Z"), ZoneId.of("UTC"));
+        LocalDateTime dateTime = LocalDateTime.now(clock);
+        mockStatic(LocalDateTime.class);
+        when(LocalDateTime.now()).thenReturn(dateTime);
+        String dateTimeExpected = "2014-12-22T10:15:30";
+
+        LocalDateTime now = LocalDateTime.now();
+
+        assertThat(now).isEqualTo(dateTimeExpected);
+    }
+
+    @Test
+    public void givenFixedClock_whenNow_thenGetFixedLocalDateTime() {
+        Clock clock = Clock.fixed(Instant.parse("2014-12-22T10:15:30.00Z"), ZoneId.of("UTC"));
+        String dateTimeExpected = "2014-12-22T10:15:30";
+
+        LocalDateTime dateTime = LocalDateTime.now(clock);
+
+        assertThat(dateTime).isEqualTo(dateTimeExpected);
+    }
+}

core-java-8/src/test/java/com/baeldung/time/LocalDateTimeWithJMockUnitTest.java

@@ -0,0 +1,48 @@
+package com.baeldung.time;
+
+import mockit.Expectations;
+import mockit.Mock;
+import mockit.MockUp;
+import org.junit.jupiter.api.Test;
+
+import java.time.Clock;
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class LocalDateTimeWithJMockUnitTest {
+
+    @Test
+    public void givenLocalDateTimeWithJMock_whenNow_thenGetFixedLocalDateTime() {
+        Clock clock = Clock.fixed(Instant.parse("2014-12-21T10:15:30.00Z"), ZoneId.of("UTC"));
+        new MockUp<LocalDateTime>() {
+            @Mock
+            public LocalDateTime now() {
+                return LocalDateTime.now(clock);
+            }
+        };
+        String dateTimeExpected = "2014-12-21T10:15:30";
+
+        LocalDateTime now = LocalDateTime.now();
+
+        assertThat(now).isEqualTo(dateTimeExpected);
+    }
+
+    @Test
+    public void givenLocalDateTimeWithExpectations_whenNow_thenGetFixedLocalDateTime() {
+        Clock clock = Clock.fixed(Instant.parse("2014-12-23T10:15:30.00Z"), ZoneId.of("UTC"));
+        LocalDateTime dateTimeExpected = LocalDateTime.now(clock);
+        new Expectations(LocalDateTime.class) {
+            {
+                LocalDateTime.now();
+                result = dateTimeExpected;
+            }
+        };
+
+        LocalDateTime now = LocalDateTime.now();
+
+        assertThat(now).isEqualTo(dateTimeExpected);
+    }
+}