diff --git a/core-java-modules/core-java-io-apis-2/pom.xml b/core-java-modules/core-java-io-apis-2/pom.xml
index 579fa4a589..976cbd62e4 100644
--- a/core-java-modules/core-java-io-apis-2/pom.xml
+++ b/core-java-modules/core-java-io-apis-2/pom.xml
@@ -81,6 +81,12 @@
             <version>7.1.0</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>3.4.1</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
     <build>
         <finalName>core-java-io-apis-2</finalName>
@@ -94,4 +100,5 @@
     <properties>
         <junit-jupiter-version>5.9.3</junit-jupiter-version>
     </properties>
-</project>
\ No newline at end of file
+
+</project>
diff --git a/core-java-modules/core-java-io-apis-2/src/test/java/com/baeldung/inputstream/InputStreamUnitTest.java b/core-java-modules/core-java-io-apis-2/src/test/java/com/baeldung/inputstream/InputStreamUnitTest.java
index a1b0ef251c..e253690762 100644
--- a/core-java-modules/core-java-io-apis-2/src/test/java/com/baeldung/inputstream/InputStreamUnitTest.java
+++ b/core-java-modules/core-java-io-apis-2/src/test/java/com/baeldung/inputstream/InputStreamUnitTest.java
@@ -1,6 +1,6 @@
 package com.baeldung.inputstream;
 
-import static org.junit.jupiter.api.io.CleanupMode.ALWAYS;
+import static org.assertj.core.api.Assertions.assertThat;
 
 import java.io.ByteArrayInputStream;
 import java.io.File;
@@ -20,21 +20,20 @@ import java.util.Map;
 import org.junit.Assert;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
-
 public class InputStreamUnitTest {
-    @Test
-    public void givenAString_whenWrittenToFileInputStream_thenShouldMatchWhenRead(@TempDir Path tempDir) throws IOException {
+    @Test //givenAStringWrittenToAFile_whenReadByX_thenY
+    public void givenAStringWrittenToFile_whenReadWithFileInputStream_thenItShouldExitsInTheInputStream(@TempDir Path tempDir) throws IOException {
         Path sampleOut = tempDir.resolve("sample-out.txt");
         List<String> lines = Arrays.asList("Hello. This is just a test. Good bye.");
         Files.write(sampleOut, lines);
         File sampleOutFile = sampleOut.toFile();
         try (InputStream inputStream = new FileInputStream(sampleOutFile)) {
-            Assert.assertTrue(readString(inputStream).contains(lines.get(0)));
+            assertThat(readString(inputStream)).contains(lines.get(0));
         }
     }
 
     @Test
-    public void givenAString_whenWrittenToFileInputStreamWithStringConstructor_thenShouldMatchWhenRead(@TempDir Path tempDir) throws IOException {
+    public void givenAStringWrittenToFile_whenReadWithFileInputStreamWithStringConstructor_thenItShouldExitsInTheInputStream(@TempDir Path tempDir) throws IOException {
         Path sampleOut = tempDir.resolve("sample-out.txt");
         String expectedText = "Hello. Hi.";
         List<String> lines = Arrays.asList(expectedText);
@@ -43,23 +42,40 @@ public class InputStreamUnitTest {
             .getAbsolutePath();
         try (FileInputStream fis = new FileInputStream(fileAbsolutePath)) {
             int content;
-            int availabeBytes = fis.available();
-            Assert.assertTrue(availabeBytes > 0);
+            int availableBytes = fis.available();
+            Assert.assertTrue(availableBytes > 0);
             StringBuilder actualReadText = new StringBuilder();
             while ((content = fis.read()) != -1) {
                 actualReadText.append((char) content);
             }
-            Assert.assertTrue(actualReadText.toString()
-                .contains(expectedText));
+            assertThat(actualReadText.toString()).contains(expectedText);
         }
     }
 
     @Test
-    public void givenAString_whenWrittenToByteArrayInputStream_thenShouldMatchWhenRead() throws IOException {
+    public void givenAByteArray_whenReadWithByteArrayInputStream_thenTheStringValueOfTheByteArrayShouldMatchTheExpectedString() throws IOException {
         byte[] byteArray = { 104, 101, 108, 108, 111 };
         try (ByteArrayInputStream bais = new ByteArrayInputStream(byteArray)) {
-            String expected = readString(bais);
-            Assert.assertEquals("hello", expected);
+            assertThat(readString(bais)).isEqualTo("hello");
+        }
+    }
+    @Test
+    public void givenKeyValuePairsWrittenInAFile_whenPassedInOutputStreams_thenThePairsShouldExistsInObjectInputStreams(
+          @TempDir Path tempDir) throws IOException, ClassNotFoundException {
+        Path sampleOut = tempDir.resolve("sample-out.txt");
+        File fileText = sampleOut.toFile();
+        //Serialize a Hashmap then write it into a file.
+        Map<String, String> kv = new HashMap<>();
+        try (ObjectOutputStream objectOutStream = new ObjectOutputStream(new FileOutputStream(fileText))) {
+                kv.put("baseURL", "baeldung.com");
+                kv.put("apiKey", "this_is_a_test_key");
+                objectOutStream.writeObject(kv);
+        }
+        //Deserialize the contents of a file then transform it back into a Hashmap
+        try (ObjectInputStream input = new ObjectInputStream(new FileInputStream(fileText))) {
+                HashMap<String, String> inputKv = (HashMap<String, String>) input.readObject();
+                assertThat(kv.get("baseURL")).isEqualTo( inputKv.get("baseURL"));
+                assertThat(kv.get("apiKey")).isEqualTo( inputKv.get("apiKey"));
         }
     }
 
@@ -72,27 +88,4 @@ public class InputStreamUnitTest {
         return sb.toString();
     }
 
-    @Test
-    public void givenKeyValuePairs_whenWrittenInATextFile_thenSuccessWhenParsedWithObjectInputStream(
-          @TempDir(cleanup = ALWAYS) Path tempDir) throws IOException, ClassNotFoundException {
-        Path sampleOut = tempDir.resolve("sample-out.txt");
-        File fileText = sampleOut.toFile();
-        //Serialize a Hashmap then write it into a file.
-        Map<String, String> kv = new HashMap<>();
-        try (FileOutputStream fileOutStream = new FileOutputStream(fileText)) {
-            try (ObjectOutputStream objectOutStream = new ObjectOutputStream(fileOutStream)) {
-                kv.put("baseURL", "baeldung.com");
-                kv.put("apiKey", "this_is_a_test_key");
-                objectOutStream.writeObject(kv);
-            }
-        }
-        //Deserialize the contents of a file then transform it back into a Hashmap
-        try (FileInputStream fileStream = new FileInputStream(fileText)) {
-            try (ObjectInputStream input = new ObjectInputStream(fileStream)) {
-                HashMap<String, String> inputKv = (HashMap<String, String>) input.readObject();
-                Assert.assertEquals(kv.get("baseURL"), inputKv.get("baseURL"));
-                Assert.assertEquals(kv.get("apiKey"), inputKv.get("apiKey"));
-            }
-        }
-    }
 }
diff --git a/core-java-modules/core-java-io-apis-2/src/test/java/com/baeldung/inputstreamreader/InputStreamReaderUnitTest.java b/core-java-modules/core-java-io-apis-2/src/test/java/com/baeldung/inputstreamreader/InputStreamReaderUnitTest.java
index ea4572fa5f..2dfcc4f9e7 100644
--- a/core-java-modules/core-java-io-apis-2/src/test/java/com/baeldung/inputstreamreader/InputStreamReaderUnitTest.java
+++ b/core-java-modules/core-java-io-apis-2/src/test/java/com/baeldung/inputstreamreader/InputStreamReaderUnitTest.java
@@ -1,5 +1,7 @@
 package com.baeldung.inputstreamreader;
 
+import static org.assertj.core.api.Assertions.assertThat;
+
 import java.io.BufferedReader;
 import java.io.FileInputStream;
 import java.io.IOException;
@@ -10,10 +12,8 @@ import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.List;
 
-import org.junit.Assert;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
-
 public class InputStreamReaderUnitTest {
     @Test
     public void givenAStringWrittenToAFile_whenReadByInputStreamReader_thenShouldMatchWhenRead(@TempDir Path tempDir) throws IOException {
@@ -21,9 +21,9 @@ public class InputStreamReaderUnitTest {
         String sampleTxt = "Good day. This is just a test. Good bye.";
         Path sampleOut = tempDir.resolve("sample-out.txt");
         List<String> lines = Arrays.asList(sampleTxt);
-        //create and write file
         Files.write(sampleOut, lines);
-        try (FileInputStream fis = new FileInputStream(String.valueOf(sampleOut.toAbsolutePath())); BufferedReader br = new BufferedReader(new InputStreamReader(fis, StandardCharsets.UTF_8))) {
+        String absolutePath = String.valueOf(sampleOut.toAbsolutePath());
+        try (BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(absolutePath), StandardCharsets.UTF_8))) {
             String ln;
             while ((ln = br.readLine()) != null) {
                 if (ln.contains(sampleTxt)) {
@@ -31,7 +31,7 @@ public class InputStreamReaderUnitTest {
                     break;
                 }
             }
-            Assert.assertTrue(isMatched);
+            assertThat(isMatched).isTrue();
         }
     }
 }