core java cleanup

core-java/src/main/java/org/baeldung/equalshashcode/entities/ComplexClass.java

@@ -1,7 +1,5 @@
 package org.baeldung.equalshashcode.entities;
 
-import java.util.ArrayList;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
@@ -10,7 +8,7 @@ public class ComplexClass {
     private List<?> genericList;
     private Set<Integer> integerSet;
 
-    public ComplexClass(ArrayList<?> genericArrayList, HashSet<Integer> integerHashSet) {
+    public ComplexClass(List<?> genericArrayList, Set<Integer> integerHashSet) {
         super();
         this.genericList = genericArrayList;
         this.integerSet = integerHashSet;

core-java/src/test/java/com/baeldung/CharToStringUnitTest.java

@@ -4,7 +4,7 @@ import org.junit.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class CharToStringTest {
+public class CharToStringUnitTest {
 
     @Test
     public void givenChar_whenCallingStringValueOf_shouldConvertToString() {

core-java/src/test/java/com/baeldung/collectors/Java8CollectorsUnitTest.java

@@ -36,7 +36,7 @@ import static java.util.stream.Collectors.toSet;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
-public class Java8CollectorsTest {
+public class Java8CollectorsUnitTest {
 
     private final List<String> givenList = Arrays.asList("a", "bb", "ccc", "dd");
 

core-java/src/test/java/com/baeldung/file/FileOperationsUnitTest.java

@@ -1,11 +1,5 @@
 package com.baeldung.file;
 
-import org.apache.commons.io.FileUtils;
-import org.hamcrest.CoreMatchers;
-import org.hamcrest.Matchers;
-import org.junit.Assert;
-import org.junit.Test;
-
 import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileInputStream;
@@ -20,7 +14,13 @@ import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.stream.Stream;
 
-public class FileOperationsTest {
+import org.apache.commons.io.FileUtils;
+import org.hamcrest.CoreMatchers;
+import org.hamcrest.Matchers;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class FileOperationsUnitTest {
 
     @Test
     public void givenFileName_whenUsingClassloader_thenFileData() throws IOException {
@@ -38,7 +38,7 @@ public class FileOperationsTest {
     public void givenFileNameAsAbsolutePath_whenUsingClasspath_thenFileData() throws IOException {
         String expectedData = "Hello World from fileTest.txt!!!";
 
-        Class clazz = FileOperationsTest.class;
+        Class clazz = FileOperationsUnitTest.class;
         InputStream inputStream = clazz.getResourceAsStream("/fileTest.txt");
         String data = readFromInputStream(inputStream);
 

core-java/src/test/java/com/baeldung/java/nio/selector/NioEchoIntegrationTest.java

@@ -6,7 +6,7 @@ import java.io.IOException;
 
 import org.junit.Test;
 
-public class EchoTest {
+public class NioEchoIntegrationTest {
 
     @Test
     public void givenClient_whenServerEchosMessage_thenCorrect() throws IOException, InterruptedException {

core-java/src/test/java/com/baeldung/java8/Java8DefaultStaticIntefaceMethodsUnitTest.java

@@ -6,7 +6,7 @@ import org.junit.Test;
 
 import static org.junit.Assert.assertEquals;
 
-public class Java8DefaultStaticIntefaceMethodsTest {
+public class Java8DefaultStaticIntefaceMethodsUnitTest {
 
     @Test
     public void callStaticInterfaceMethdosMethods_whenExpectedResults_thenCorrect() {

core-java/src/test/java/com/baeldung/java8/Java8ExecutorServiceIntegrationTest.java

@@ -1,17 +1,26 @@
 package com.baeldung.java8;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
 
 import org.junit.Before;
 import org.junit.Test;
 
-import java.util.ArrayList;
+public class Java8ExecutorServiceIntegrationTest {
-import java.util.List;
-import java.util.concurrent.*;
-
-import static org.junit.Assert.*;
-
-
-public class Java8ExecutorServiceTest {
 
     private Runnable runnableTask;
     private Callable<String> callableTask;
@@ -53,9 +62,7 @@ public class Java8ExecutorServiceTest {
     @Test
     public void creationSubmittingTasksShuttingDownNow_whenShutDownAfterAwating_thenCorrect() {
 
-        ExecutorService threadPoolExecutor =
+        ExecutorService threadPoolExecutor = new ThreadPoolExecutor(1, 1, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<>());
-                new ThreadPoolExecutor(1, 1, 0L, TimeUnit.MILLISECONDS,
-                        new LinkedBlockingQueue<>());
 
         for (int i = 0; i < 100; i++) {
             threadPoolExecutor.submit(callableTask);
@@ -138,8 +145,7 @@ public class Java8ExecutorServiceTest {
     @Test
     public void submittingTaskScheduling_whenExecuted_thenCorrect() {
 
-        ScheduledExecutorService executorService = Executors
+        ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
-                .newSingleThreadScheduledExecutor();
 
         Future<String> resultFuture = executorService.schedule(callableTask, 1, TimeUnit.SECONDS);
         String result = null;

core-java/src/test/java/com/baeldung/java8/Java8ForkJoinIntegrationTest.java

@@ -1,18 +1,20 @@
 package com.baeldung.java8;
 
-
+import static org.junit.Assert.assertEquals;
-import com.baeldung.forkjoin.CustomRecursiveAction;
+import static org.junit.Assert.assertNotNull;
-import com.baeldung.forkjoin.CustomRecursiveTask;
+import static org.junit.Assert.assertTrue;
-import com.baeldung.forkjoin.util.PoolUtil;
-import org.junit.Before;
-import org.junit.Test;
 
 import java.util.Random;
 import java.util.concurrent.ForkJoinPool;
 
-import static org.junit.Assert.*;
+import org.junit.Before;
+import org.junit.Test;
 
-public class Java8ForkJoinTest {
+import com.baeldung.forkjoin.CustomRecursiveAction;
+import com.baeldung.forkjoin.CustomRecursiveTask;
+import com.baeldung.forkjoin.util.PoolUtil;
+
+public class Java8ForkJoinIntegrationTest {
 
     private int[] arr;
     private CustomRecursiveTask customRecursiveTask;
@@ -27,28 +29,23 @@ public class Java8ForkJoinTest {
         customRecursiveTask = new CustomRecursiveTask(arr);
     }
 
-
     @Test
     public void callPoolUtil_whenExistsAndExpectedType_thenCorrect() {
-
         ForkJoinPool forkJoinPool = PoolUtil.forkJoinPool;
         ForkJoinPool forkJoinPoolTwo = PoolUtil.forkJoinPool;
 
         assertNotNull(forkJoinPool);
         assertEquals(2, forkJoinPool.getParallelism());
         assertEquals(forkJoinPool, forkJoinPoolTwo);
-
     }
 
     @Test
     public void callCommonPool_whenExistsAndExpectedType_thenCorrect() {
-
         ForkJoinPool commonPool = ForkJoinPool.commonPool();
         ForkJoinPool commonPoolTwo = ForkJoinPool.commonPool();
 
         assertNotNull(commonPool);
         assertEquals(commonPool, commonPoolTwo);
-
     }
 
     @Test
@@ -63,7 +60,6 @@ public class Java8ForkJoinTest {
 
     @Test
     public void executeRecursiveTask_whenExecuted_thenCorrect() {
-
         ForkJoinPool forkJoinPool = ForkJoinPool.commonPool();
 
         forkJoinPool.execute(customRecursiveTask);
@@ -73,12 +69,10 @@ public class Java8ForkJoinTest {
         forkJoinPool.submit(customRecursiveTask);
         int resultTwo = customRecursiveTask.join();
         assertTrue(customRecursiveTask.isDone());
-
     }
 
     @Test
     public void executeRecursiveTaskWithFJ_whenExecuted_thenCorrect() {
-
         CustomRecursiveTask customRecursiveTaskFirst = new CustomRecursiveTask(arr);
         CustomRecursiveTask customRecursiveTaskSecond = new CustomRecursiveTask(arr);
         CustomRecursiveTask customRecursiveTaskLast = new CustomRecursiveTask(arr);
@@ -95,6 +89,6 @@ public class Java8ForkJoinTest {
         assertTrue(customRecursiveTaskSecond.isDone());
         assertTrue(customRecursiveTaskLast.isDone());
         assertTrue(result != 0);
-
     }
+
 }

core-java/src/test/java/com/baeldung/java8/Java8FunctionalInteracesLambdasUnitTest.java

@@ -11,7 +11,7 @@ import java.util.function.Function;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotEquals;
 
-public class Java8FunctionalInteracesLambdasTest {
+public class Java8FunctionalInteracesLambdasUnitTest {
 
     private UseFoo useFoo;
 

core-java/src/test/java/com/baeldung/java8/Java8MethodReferenceUnitTest.java

@@ -12,7 +12,7 @@ import java.util.stream.Stream;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
-public class Java8MethodReferenceTest {
+public class Java8MethodReferenceUnitTest {
 
     private List<String> list;
 

core-java/src/test/java/com/baeldung/java8/Java8OptionalUnitTest.java

@@ -1,16 +1,23 @@
 package com.baeldung.java8;
 
-import com.baeldung.java_8_features.*;
+import static org.junit.Assert.assertEquals;
-import org.junit.Before;
+import static org.junit.Assert.assertFalse;
-import org.junit.Test;
+import static org.junit.Assert.assertTrue;
 
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 
-import static org.junit.Assert.*;
+import org.junit.Before;
+import org.junit.Test;
 
-public class Java8OptionalTest {
+import com.baeldung.java_8_features.Address;
+import com.baeldung.java_8_features.CustomException;
+import com.baeldung.java_8_features.OptionalAddress;
+import com.baeldung.java_8_features.OptionalUser;
+import com.baeldung.java_8_features.User;
+
+public class Java8OptionalUnitTest {
 
     private List<String> list;
 
@@ -32,7 +39,6 @@ public class Java8OptionalTest {
 
     @Test
     public void checkOptional_whenAsExpected_thenCorrect() {
-
         Optional<String> optionalEmpty = Optional.empty();
         assertFalse(optionalEmpty.isPresent());
 
@@ -52,27 +58,19 @@ public class Java8OptionalTest {
         assertTrue(listOptNull.isEmpty());
 
         Optional<User> user = Optional.ofNullable(getUser());
-        String result = user.map(User::getAddress)
+        String result = user.map(User::getAddress).map(Address::getStreet).orElse("not specified");
-                .map(Address::getStreet)
-                .orElse("not specified");
         assertEquals(result, "1st Avenue");
 
         Optional<OptionalUser> optionalUser = Optional.ofNullable(getOptionalUser());
-        String resultOpt = optionalUser.flatMap(OptionalUser::getAddress)
+        String resultOpt = optionalUser.flatMap(OptionalUser::getAddress).flatMap(OptionalAddress::getStreet).orElse("not specified");
-                .flatMap(OptionalAddress::getStreet)
-                .orElse("not specified");
         assertEquals(resultOpt, "1st Avenue");
 
         Optional<User> userNull = Optional.ofNullable(getUserNull());
-        String resultNull = userNull.map(User::getAddress)
+        String resultNull = userNull.map(User::getAddress).map(Address::getStreet).orElse("not specified");
-                .map(Address::getStreet)
-                .orElse("not specified");
         assertEquals(resultNull, "not specified");
 
         Optional<OptionalUser> optionalUserNull = Optional.ofNullable(getOptionalUserNull());
-        String resultOptNull = optionalUserNull.flatMap(OptionalUser::getAddress)
+        String resultOptNull = optionalUserNull.flatMap(OptionalUser::getAddress).flatMap(OptionalAddress::getStreet).orElse("not specified");
-                .flatMap(OptionalAddress::getStreet)
-                .orElse("not specified");
         assertEquals(resultOptNull, "not specified");
 
     }

core-java/src/test/java/com/baeldung/java8/base64/ApacheCommonsEncodeDecodeUnitTest.java

@@ -7,7 +7,7 @@ import java.io.UnsupportedEncodingException;
 
 import static org.junit.Assert.*;
 
-public class ApacheCommonsEncodeDecodeTest {
+public class ApacheCommonsEncodeDecodeUnitTest {
 
     // tests
 

core-java/src/test/java/com/baeldung/java8/base64/Java8EncodeDecodeUnitTest.java

@@ -8,7 +8,7 @@ import java.util.UUID;
 
 import static org.junit.Assert.*;
 
-public class Java8EncodeDecodeTest {
+public class Java8EncodeDecodeUnitTest {
 
     // tests
 

core-java/src/test/java/com/baeldung/socket/EchoIntegrationTest.java

@@ -1,15 +1,15 @@
 package com.baeldung.socket;
 
+import static org.junit.Assert.assertEquals;
+
+import java.util.concurrent.Executors;
+
 import org.junit.After;
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
-import java.util.concurrent.Executors;
+public class EchoIntegrationTest {
-
-import static org.junit.Assert.assertEquals;
-
-public class EchoTest {
     private static final Integer PORT = 4444;
 
     @BeforeClass
@@ -25,9 +25,15 @@ public class EchoTest {
         client.startConnection("127.0.0.1", PORT);
     }
 
+    @After
+    public void tearDown() {
+        client.stopConnection();
+    }
+
+    //
+
     @Test
     public void givenClient_whenServerEchosMessage_thenCorrect() {
-
         String resp1 = client.sendMessage("hello");
         String resp2 = client.sendMessage("world");
         String resp3 = client.sendMessage("!");
@@ -38,8 +44,4 @@ public class EchoTest {
         assertEquals("good bye", resp4);
     }
 
-    @After
-    public void tearDown() {
-        client.stopConnection();
-    }
 }

core-java/src/test/java/com/baeldung/socket/SocketEchoMultiIntegrationTest.java

@@ -7,7 +7,7 @@ import java.util.concurrent.Executors;
 
 import static org.junit.Assert.assertEquals;
 
-public class EchoMultiTest {
+public class SocketEchoMultiIntegrationTest {
 
     private static final Integer PORT = 5555;
 

core-java/src/test/java/com/baeldung/threadpool/CoreThreadPoolIntegrationTest.java

@@ -1,13 +1,23 @@
 package com.baeldung.threadpool;
 
-import java.util.concurrent.*;
+import static org.junit.Assert.assertEquals;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executor;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ForkJoinPool;
+import java.util.concurrent.Future;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import org.junit.Test;
 
-import static org.junit.Assert.assertEquals;
+public class CoreThreadPoolIntegrationTest {
-
-public class CoreThreadPoolTest {
 
     @Test(timeout = 1000)
     public void whenCallingExecuteWithRunnable_thenRunnableIsExecuted() throws InterruptedException {
@@ -132,9 +142,7 @@ public class CoreThreadPoolTest {
     @Test
     public void whenUsingForkJoinPool_thenSumOfTreeElementsIsCalculatedCorrectly() {
 
-        TreeNode tree = new TreeNode(5,
+        TreeNode tree = new TreeNode(5, new TreeNode(3), new TreeNode(2, new TreeNode(2), new TreeNode(8)));
-                new TreeNode(3), new TreeNode(2,
-                new TreeNode(2), new TreeNode(8)));
 
         ForkJoinPool forkJoinPool = ForkJoinPool.commonPool();
         int sum = forkJoinPool.invoke(new CountingTask(tree));
@@ -142,5 +150,4 @@ public class CoreThreadPoolTest {
         assertEquals(20, sum);
     }
 
-
 }

core-java/src/test/java/com/baeldung/threadpool/GuavaThreadPoolIntegrationTest.java

@@ -16,7 +16,7 @@ import org.junit.Test;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
-public class GuavaThreadPoolTest {
+public class GuavaThreadPoolIntegrationTest {
 
     @Test
     public void whenExecutingTaskWithDirectExecutor_thenTheTaskIsExecutedInTheCurrentThread() {

core-java/src/test/java/com/baeldung/util/CurrentDateTimeUnitTest.java

@@ -1,19 +1,22 @@
 package com.baeldung.util;
 
-import org.junit.Test;
-
-import java.time.*;
-import java.time.temporal.ChronoField;
-
 import static org.junit.Assert.assertEquals;
 
-public class CurrentDateTimeTest {
+import java.time.Clock;
+import java.time.Instant;
+import java.time.LocalDate;
+import java.time.LocalTime;
+import java.time.ZoneId;
+import java.time.temporal.ChronoField;
+
+import org.junit.Test;
+
+public class CurrentDateTimeUnitTest {
 
     private static final Clock clock = Clock.fixed(Instant.parse("2016-10-09T15:10:30.00Z"), ZoneId.of("UTC"));
 
     @Test
     public void shouldReturnCurrentDate() {
-
         final LocalDate now = LocalDate.now(clock);
 
         assertEquals(9, now.get(ChronoField.DAY_OF_MONTH));
@@ -23,7 +26,6 @@ public class CurrentDateTimeTest {
 
     @Test
     public void shouldReturnCurrentTime() {
-
         final LocalTime now = LocalTime.now(clock);
 
         assertEquals(15, now.get(ChronoField.HOUR_OF_DAY));
@@ -33,9 +35,9 @@ public class CurrentDateTimeTest {
 
     @Test
     public void shouldReturnCurrentTimestamp() {
-
         final Instant now = Instant.now(clock);
 
         assertEquals(clock.instant().getEpochSecond(), now.getEpochSecond());
     }
+
 }

core-java/src/test/java/org/baeldung/core/exceptions/FileNotFoundExceptionUnitTest.java

@@ -1,13 +1,17 @@
 package org.baeldung.core.exceptions;
 
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+
 import org.apache.log4j.Logger;
 import org.junit.Test;
 
-import java.io.*;
+public class FileNotFoundExceptionUnitTest {
 
-public class FileNotFoundExceptionTest {
+    private static final Logger LOG = Logger.getLogger(FileNotFoundExceptionUnitTest.class);
-
-    private static final Logger LOG = Logger.getLogger(FileNotFoundExceptionTest.class);
 
     private String fileName = Double.toString(Math.random());
 

core-java/src/test/java/org/baeldung/equalshashcode/entities/ComplexClassUnitTest.java

@@ -2,22 +2,22 @@ package org.baeldung.equalshashcode.entities;
 
 import java.util.ArrayList;
 import java.util.HashSet;
+import java.util.List;
 
 import org.junit.Assert;
 import org.junit.Test;
 
-public class ComplexClassTest {
+public class ComplexClassUnitTest {
 
     @Test
     public void testEqualsAndHashcodes() {
-
+        List<String> strArrayList = new ArrayList<String>();
-        ArrayList<String> strArrayList = new ArrayList<String>();
         strArrayList.add("abc");
         strArrayList.add("def");
         ComplexClass aObject = new ComplexClass(strArrayList, new HashSet<Integer>(45, 67));
         ComplexClass bObject = new ComplexClass(strArrayList, new HashSet<Integer>(45, 67));
 
-        ArrayList<String> strArrayListD = new ArrayList<String>();
+        List<String> strArrayListD = new ArrayList<String>();
         strArrayListD.add("lmn");
         strArrayListD.add("pqr");
         ComplexClass dObject = new ComplexClass(strArrayListD, new HashSet<Integer>(45, 67));

core-java/src/test/java/org/baeldung/java/collections/ArrayListUnitTest.java

@@ -12,7 +12,7 @@ import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.core.IsNot.not;
 import static org.junit.Assert.*;
 
-public class ArrayListTest {
+public class ArrayListUnitTest {
 
     private List<String> stringsToSearch;