BAEL-3927 : Encode a String to UTF-8 in Java (#8954)

* BAEL-3927 : Encode a String to UTF-8 in Java

* Update core-java-modules/core-java-string-operations-2/src/test/java/com/baeldung/encode/StringEncodeUnitTest.java

Co-Authored-By: KevinGilmore <kpg102@gmail.com>

* BAEL-3927 : Applying suggested adjustments

* BAEL-3927 : Simplifying the code snippets

* BAEL-3927 : Coding styles adjustements

* BAEL-3927 : Test adjustements to fit changes in article

Co-authored-by: KevinGilmore <kpg102@gmail.com>

core-java-modules/core-java-string-operations-2/src/test/java/com/baeldung/encodetoutf8/StringEncodeUnitTest.java

@@ -0,0 +1,73 @@
+package com.baeldung.encodetoutf8;
+
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
+
+import org.apache.commons.codec.binary.StringUtils;
+import org.junit.Test;
+
+public class StringEncodeUnitTest {
+
+    @Test
+    public void givenGermanAsciiString_whenComparing_thenCompareNotEquals() {
+        String germanString = "Entwickeln Sie mit Vergnügen";
+        byte[] germanBytes = germanString.getBytes();
+
+        String asciiEncodedString = new String(germanBytes, StandardCharsets.US_ASCII);
+
+        assertNotEquals(germanString, asciiEncodedString);
+    }
+
+    @Test
+    public void givenUsAsciiString_whenComparing_thenCompareNotEquals() {
+        String englishString = "Develop with pleasure";
+        byte[] englishBytes = englishString.getBytes();
+
+        String asciiEncondedEnglishString = new String(englishBytes, StandardCharsets.US_ASCII);
+
+        assertEquals(englishString, asciiEncondedEnglishString);
+    }
+
+    /*
+     * ApacheCommonsCodecEncode
+     */
+    @Test
+    public void givenSomeUnencodedString_whenApacheCommonsCodecEncode_thenCompareEquals() {
+        String rawString = "Entwickeln Sie mit Vergnügen";
+        byte[] bytes = StringUtils.getBytesUtf8(rawString);
+
+        String utf8EncodedString = StringUtils.newStringUtf8(bytes);
+
+        assertEquals(rawString, utf8EncodedString);
+    }
+
+    /*
+     * CoreJavaEncode
+     */
+    @Test
+    public void givenSomeUnencodedString_whenCoreJavaEncode_thenCompareEquals() {
+        String rawString = "Entwickeln Sie mit Vergnügen";
+        byte[] bytes = rawString.getBytes(StandardCharsets.UTF_8);
+
+        String utf8EncodedString = new String(bytes, StandardCharsets.UTF_8);
+
+        assertEquals(rawString, utf8EncodedString);
+    }
+
+    /*
+     * Java7StandardCharsetsEncode
+     */
+    @Test
+    public void givenSomeUnencodedString_whenJava7StandardCharsetsEncode_thenCompareEquals() {
+        String rawString = "Entwickeln Sie mit Vergnügen";
+        ByteBuffer buffer = StandardCharsets.UTF_8.encode(rawString);
+
+        String utf8EncodedString = StandardCharsets.UTF_8.decode(buffer)
+            .toString();
+
+        assertEquals(rawString, utf8EncodedString);
+    }
+}