diff --git a/smack-core/src/main/java/org/jivesoftware/smack/sasl/SASLMechanism.java b/smack-core/src/main/java/org/jivesoftware/smack/sasl/SASLMechanism.java
index 52fcdf30d..7efb2b03c 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/sasl/SASLMechanism.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/sasl/SASLMechanism.java
@@ -303,7 +303,7 @@ public abstract class SASLMechanism implements Comparable<SASLMechanism> {
     protected abstract SASLMechanism newInstance();
 
     protected static byte[] toBytes(String string) {
-        return StringUtils.toBytes(string);
+        return StringUtils.toUtf8Bytes(string);
     }
 
     /**
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/util/MD5.java b/smack-core/src/main/java/org/jivesoftware/smack/util/MD5.java
index 6de0441ee..26c0547fd 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/util/MD5.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/util/MD5.java
@@ -42,7 +42,7 @@ public class MD5 {
     }
 
     public static byte[] bytes(String string) {
-        return bytes(StringUtils.toBytes(string));
+        return bytes(StringUtils.toUtf8Bytes(string));
     }
 
     public static String hex(byte[] bytes) {
@@ -50,7 +50,7 @@ public class MD5 {
     }
 
     public static String hex(String string) {
-        return hex(StringUtils.toBytes(string));
+        return hex(StringUtils.toUtf8Bytes(string));
     }
 
 }
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/util/SHA1.java b/smack-core/src/main/java/org/jivesoftware/smack/util/SHA1.java
index 1dff5f104..89144530b 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/util/SHA1.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/util/SHA1.java
@@ -43,7 +43,7 @@ public class SHA1 {
     }
 
     public static byte[] bytes(String string) {
-        return bytes(StringUtils.toBytes(string));
+        return bytes(StringUtils.toUtf8Bytes(string));
     }
 
     public static String hex(byte[] bytes) {
@@ -51,7 +51,7 @@ public class SHA1 {
     }
 
     public static String hex(String string) {
-        return hex(StringUtils.toBytes(string));
+        return hex(StringUtils.toUtf8Bytes(string));
     }
 
 }
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java b/smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java
index 77dd81141..ecba3ea7d 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java
@@ -244,7 +244,7 @@ public class StringUtils {
         return new String(hexChars);
     }
 
-    public static byte[] toBytes(String string) {
+    public static byte[] toUtf8Bytes(String string) {
         try {
             return string.getBytes(StringUtils.UTF8);
         }
diff --git a/smack-core/src/test/java/org/jivesoftware/smack/sasl/DigestMd5SaslTest.java b/smack-core/src/test/java/org/jivesoftware/smack/sasl/DigestMd5SaslTest.java
index 04a0cbf3a..05f3b1469 100644
--- a/smack-core/src/test/java/org/jivesoftware/smack/sasl/DigestMd5SaslTest.java
+++ b/smack-core/src/test/java/org/jivesoftware/smack/sasl/DigestMd5SaslTest.java
@@ -34,7 +34,7 @@ import org.jxmpp.stringprep.XmppStringprepException;
 public class DigestMd5SaslTest extends AbstractSaslTest {
 
     protected static final String challenge = "realm=\"xmpp.org\",nonce=\"jgGgnz+cQcmyVaAs2n88kQ==\",qop=\"auth\",charset=utf-8,algorithm=md5-sess";
-    protected static final byte[] challengeBytes = StringUtils.toBytes(challenge);
+    protected static final byte[] challengeBytes = StringUtils.toUtf8Bytes(challenge);
 
     public DigestMd5SaslTest(SASLMechanism saslMechanism) {
         super(saslMechanism);
diff --git a/smack-experimental/src/main/java/org/jivesoftware/smackx/hashes/HashManager.java b/smack-experimental/src/main/java/org/jivesoftware/smackx/hashes/HashManager.java
index 4101231b3..e4607ad4d 100644
--- a/smack-experimental/src/main/java/org/jivesoftware/smackx/hashes/HashManager.java
+++ b/smack-experimental/src/main/java/org/jivesoftware/smackx/hashes/HashManager.java
@@ -16,6 +16,8 @@
  */
 package org.jivesoftware.smackx.hashes;
 
+import static org.jivesoftware.smack.util.StringUtils.encodeHex;
+import static org.jivesoftware.smack.util.StringUtils.toUtf8Bytes;
 import static org.jivesoftware.smackx.hashes.HashManager.ALGORITHM.BLAKE2B160;
 import static org.jivesoftware.smackx.hashes.HashManager.ALGORITHM.BLAKE2B256;
 import static org.jivesoftware.smackx.hashes.HashManager.ALGORITHM.BLAKE2B384;
@@ -31,8 +33,6 @@ import static org.jivesoftware.smackx.hashes.HashManager.ALGORITHM.SHA_256;
 import static org.jivesoftware.smackx.hashes.HashManager.ALGORITHM.SHA_384;
 import static org.jivesoftware.smackx.hashes.HashManager.ALGORITHM.SHA_512;
 
-import java.io.UnsupportedEncodingException;
-import java.math.BigInteger;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
@@ -44,7 +44,6 @@ import java.util.WeakHashMap;
 
 import org.jivesoftware.smack.Manager;
 import org.jivesoftware.smack.XMPPConnection;
-import org.jivesoftware.smack.util.StringUtils;
 
 import org.jivesoftware.smackx.disco.ServiceDiscoveryManager;
 import org.jivesoftware.smackx.hashes.element.HashElement;
@@ -190,8 +189,10 @@ public final class HashManager extends Manager {
 
         /**
          * Compensational method for static 'valueOf' function.
+         *
          * @param s
-         * @return
+         * @return the algorithm for the given string.
+         * @throws IllegalArgumentException if no algorithm for the given string is known.
          */
         public static ALGORITHM valueOfName(String s) {
             for (ALGORITHM a : ALGORITHM.values()) {
@@ -205,16 +206,17 @@ public final class HashManager extends Manager {
 
     /**
      * Calculate the hash sum of data using algorithm.
-     * @param algorithm
-     * @param data
-     * @return
+     *
+     * @param algorithm the algorithm to use.
+     * @param data the data to calculate the hash for.
+     * @return the hash value produced by the given algorithm for the given data.
      */
     public static byte[] hash(ALGORITHM algorithm, byte[] data) {
         return getMessageDigest(algorithm).digest(data);
     }
 
     public static byte[] hash(ALGORITHM algorithm, String data) {
-        return hash(algorithm, utf8(data));
+        return hash(algorithm, toUtf8Bytes(data));
     }
 
     public static MessageDigest getMessageDigest(ALGORITHM algorithm) {
@@ -264,7 +266,7 @@ public final class HashManager extends Manager {
                     md = MessageDigest.getInstance("BLAKE2b-512", PROVIDER);
                     break;
                 default:
-                    throw new AssertionError("Invalid enum value.");
+                    throw new AssertionError("Invalid enum value: " + algorithm);
             }
             return md;
         } catch (NoSuchAlgorithmException | NoSuchProviderException e) {
@@ -277,15 +279,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] md5(String data) {
-        return md5(utf8(data));
+        return md5(toUtf8Bytes(data));
     }
 
     public static String md5HexString(byte[] data) {
-        return hex(md5(data));
+        return encodeHex(md5(data));
     }
 
     public static String md5HexString(String data) {
-        return hex(md5(data));
+        return encodeHex(md5(data));
     }
 
     public static byte[] sha_1(byte[] data) {
@@ -293,15 +295,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha_1(String data) {
-        return sha_1(utf8(data));
+        return sha_1(toUtf8Bytes(data));
     }
 
     public static String sha_1HexString(byte[] data) {
-        return hex(sha_1(data));
+        return encodeHex(sha_1(data));
     }
 
     public static String sha_1HexString(String data) {
-        return hex(sha_1(data));
+        return encodeHex(sha_1(data));
     }
 
     public static byte[] sha_224(byte[] data) {
@@ -309,15 +311,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha_224(String data) {
-        return sha_224(utf8(data));
+        return sha_224(toUtf8Bytes(data));
     }
 
     public static String sha_224HexString(byte[] data) {
-        return hex(sha_224(data));
+        return encodeHex(sha_224(data));
     }
 
     public static String sha_224HexString(String data) {
-        return hex(sha_224(data));
+        return encodeHex(sha_224(data));
     }
 
     public static byte[] sha_256(byte[] data) {
@@ -325,15 +327,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha_256(String data) {
-        return sha_256(utf8(data));
+        return sha_256(toUtf8Bytes(data));
     }
 
     public static String sha_256HexString(byte[] data) {
-        return hex(sha_256(data));
+        return encodeHex(sha_256(data));
     }
 
     public static String sha_256HexString(String data) {
-        return hex(sha_256(data));
+        return encodeHex(sha_256(data));
     }
 
     public static byte[] sha_384(byte[] data) {
@@ -341,15 +343,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha_384(String data) {
-        return sha_384(utf8(data));
+        return sha_384(toUtf8Bytes(data));
     }
 
     public static String sha_384HexString(byte[] data) {
-        return hex(sha_384(data));
+        return encodeHex(sha_384(data));
     }
 
     public static String sha_384HexString(String data) {
-        return hex(sha_384(data));
+        return encodeHex(sha_384(data));
     }
 
     public static byte[] sha_512(byte[] data) {
@@ -357,15 +359,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha_512(String data) {
-        return sha_512(utf8(data));
+        return sha_512(toUtf8Bytes(data));
     }
 
     public static String sha_512HexString(byte[] data) {
-        return hex(sha_512(data));
+        return encodeHex(sha_512(data));
     }
 
     public static String sha_512HexString(String data) {
-        return hex(sha_512(data));
+        return encodeHex(sha_512(data));
     }
 
     public static byte[] sha3_224(byte[] data) {
@@ -373,15 +375,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha3_224(String data) {
-        return sha3_224(utf8(data));
+        return sha3_224(toUtf8Bytes(data));
     }
 
     public static String sha3_224HexString(byte[] data) {
-        return hex(sha3_224(data));
+        return encodeHex(sha3_224(data));
     }
 
     public static String sha3_224HexString(String data) {
-        return hex(sha3_224(data));
+        return encodeHex(sha3_224(data));
     }
 
     public static byte[] sha3_256(byte[] data) {
@@ -389,15 +391,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha3_256(String data) {
-        return sha3_256(utf8(data));
+        return sha3_256(toUtf8Bytes(data));
     }
 
     public static String sha3_256HexString(byte[] data) {
-        return hex(sha3_256(data));
+        return encodeHex(sha3_256(data));
     }
 
     public static String sha3_256HexString(String data) {
-        return hex(sha3_256(data));
+        return encodeHex(sha3_256(data));
     }
 
     public static byte[] sha3_384(byte[] data) {
@@ -405,15 +407,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha3_384(String data) {
-        return sha3_384(utf8(data));
+        return sha3_384(toUtf8Bytes(data));
     }
 
     public static String sha3_384HexString(byte[] data) {
-        return hex(sha3_384(data));
+        return encodeHex(sha3_384(data));
     }
 
     public static String sha3_384HexString(String data) {
-        return hex(sha3_384(data));
+        return encodeHex(sha3_384(data));
     }
 
     public static byte[] sha3_512(byte[] data) {
@@ -421,15 +423,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] sha3_512(String data) {
-        return sha3_512(utf8(data));
+        return sha3_512(toUtf8Bytes(data));
     }
 
     public static String sha3_512HexString(byte[] data) {
-        return hex(sha3_512(data));
+        return encodeHex(sha3_512(data));
     }
 
     public static String sha3_512HexString(String data) {
-        return hex(sha3_512(data));
+        return encodeHex(sha3_512(data));
     }
 
     public static byte[] blake2b160(byte[] data) {
@@ -437,15 +439,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] blake2b160(String data) {
-        return blake2b160(utf8(data));
+        return blake2b160(toUtf8Bytes(data));
     }
 
     public static String blake2b160HexString(byte[] data) {
-        return hex(blake2b160(data));
+        return encodeHex(blake2b160(data));
     }
 
     public static String blake2b160HexString(String data) {
-        return hex(blake2b160(data));
+        return encodeHex(blake2b160(data));
     }
 
     public static byte[] blake2b256(byte[] data) {
@@ -453,15 +455,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] blake2b256(String data) {
-        return blake2b256(utf8(data));
+        return blake2b256(toUtf8Bytes(data));
     }
 
     public static String blake2b256HexString(byte[] data) {
-        return hex(blake2b256(data));
+        return encodeHex(blake2b256(data));
     }
 
     public static String blake2b256HexString(String data) {
-        return hex(blake2b256(data));
+        return encodeHex(blake2b256(data));
     }
 
     public static byte[] blake2b384(byte[] data) {
@@ -469,15 +471,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] blake2b384(String data) {
-        return blake2b384(utf8(data));
+        return blake2b384(toUtf8Bytes(data));
     }
 
     public static String blake2b384HexString(byte[] data) {
-        return hex(blake2b384(data));
+        return encodeHex(blake2b384(data));
     }
 
     public static  String blake2b384HexString(String data) {
-        return hex(blake2b384(data));
+        return encodeHex(blake2b384(data));
     }
 
     public static byte[] blake2b512(byte[] data) {
@@ -485,32 +487,15 @@ public final class HashManager extends Manager {
     }
 
     public static byte[] blake2b512(String data) {
-        return blake2b512(utf8(data));
+        return blake2b512(toUtf8Bytes(data));
     }
 
     public static String blake2b512HexString(byte[] data) {
-        return hex(blake2b512(data));
+        return encodeHex(blake2b512(data));
     }
 
     public static String blake2b512HexString(String data) {
-        return hex(blake2b512(data));
-    }
-
-    /**
-     * Encode a byte array in HEX.
-     * @param hash
-     * @return
-     */
-    public static String hex(byte[] hash) {
-        return new BigInteger(1, hash).toString(16);
-    }
-
-    public static byte[] utf8(String data) {
-        try {
-            return data.getBytes(StringUtils.UTF8);
-        } catch (UnsupportedEncodingException e) {
-            throw new AssertionError(e);
-        }
+        return encodeHex(blake2b512(data));
     }
 
 }
diff --git a/smack-experimental/src/test/java/org/jivesoftware/smackx/hashes/HashElementTest.java b/smack-experimental/src/test/java/org/jivesoftware/smackx/hashes/HashElementTest.java
index 2121d588d..26de91839 100644
--- a/smack-experimental/src/test/java/org/jivesoftware/smackx/hashes/HashElementTest.java
+++ b/smack-experimental/src/test/java/org/jivesoftware/smackx/hashes/HashElementTest.java
@@ -39,7 +39,7 @@ public class HashElementTest extends SmackTestSuite {
     @Test
     public void stanzaTest() throws Exception {
         String message = "Hello World!";
-        HashElement element = HashManager.calculateHashElement(SHA_256, HashManager.utf8(message));
+        HashElement element = HashManager.calculateHashElement(SHA_256, StringUtils.toUtf8Bytes(message));
         String expected = "<hash xmlns='urn:xmpp:hashes:2' algo='sha-256'>f4OxZX/x/FO5LcGBSKHWXfwtSx+j1ncoSt3SABJtkGk=</hash>";
         assertEquals(expected, element.toXML().toString());
 
diff --git a/smack-experimental/src/test/java/org/jivesoftware/smackx/hashes/HashTest.java b/smack-experimental/src/test/java/org/jivesoftware/smackx/hashes/HashTest.java
index 82d30b882..44ae4fdc5 100644
--- a/smack-experimental/src/test/java/org/jivesoftware/smackx/hashes/HashTest.java
+++ b/smack-experimental/src/test/java/org/jivesoftware/smackx/hashes/HashTest.java
@@ -19,6 +19,7 @@ package org.jivesoftware.smackx.hashes;
 import static junit.framework.TestCase.assertEquals;
 
 import org.jivesoftware.smack.test.util.SmackTestSuite;
+import org.jivesoftware.smack.util.StringUtils;
 
 import org.junit.Test;
 
@@ -47,7 +48,7 @@ public class HashTest extends SmackTestSuite {
 
     private byte[] array() {
         if (testArray == null) {
-            testArray = HashManager.utf8(testString);
+            testArray = StringUtils.toUtf8Bytes(testString);
         }
         return testArray;
     }
@@ -56,103 +57,103 @@ public class HashTest extends SmackTestSuite {
 
     @Test
     public void hashTest() {
-        assertEquals(md5sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.MD5, array())));
-        assertEquals(sha1sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA_1, array())));
-        assertEquals(sha224sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA_224, array())));
-        assertEquals(sha256sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA_256, array())));
-        assertEquals(sha384sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA_384, array())));
-        assertEquals(sha512sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA_512, array())));
-        assertEquals(sha3_224sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA3_224, array())));
-        assertEquals(sha3_256sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA3_256, array())));
-        assertEquals(sha3_384sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA3_384, array())));
-        assertEquals(sha3_512sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.SHA3_512, array())));
-        assertEquals(b2_160sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.BLAKE2B160, array())));
-        assertEquals(b2_256sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.BLAKE2B256, array())));
-        assertEquals(b2_384sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.BLAKE2B384, array())));
-        assertEquals(b2_512sum, HashManager.hex(HashManager.hash(HashManager.ALGORITHM.BLAKE2B512, array())));
+        assertEquals(md5sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.MD5, array())));
+        assertEquals(sha1sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA_1, array())));
+        assertEquals(sha224sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA_224, array())));
+        assertEquals(sha256sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA_256, array())));
+        assertEquals(sha384sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA_384, array())));
+        assertEquals(sha512sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA_512, array())));
+        assertEquals(sha3_224sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA3_224, array())));
+        assertEquals(sha3_256sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA3_256, array())));
+        assertEquals(sha3_384sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA3_384, array())));
+        assertEquals(sha3_512sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.SHA3_512, array())));
+        assertEquals(b2_160sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.BLAKE2B160, array())));
+        assertEquals(b2_256sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.BLAKE2B256, array())));
+        assertEquals(b2_384sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.BLAKE2B384, array())));
+        assertEquals(b2_512sum, StringUtils.encodeHex(HashManager.hash(HashManager.ALGORITHM.BLAKE2B512, array())));
     }
 
     @Test
     public void md5Test() {
-        String actual = HashManager.hex(HashManager.md5(array()));
+        String actual = StringUtils.encodeHex(HashManager.md5(array()));
         assertEquals(md5sum, actual);
     }
 
     @Test
     public void sha1Test() {
-        String actual = HashManager.hex(HashManager.sha_1(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha_1(array()));
         assertEquals(sha1sum, actual);
     }
 
     @Test
     public void sha224Test() {
-        String actual = HashManager.hex(HashManager.sha_224(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha_224(array()));
         assertEquals(sha224sum, actual);
     }
 
     @Test
     public void sha256Test() {
-        String actual = HashManager.hex(HashManager.sha_256(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha_256(array()));
         assertEquals(sha256sum, actual);
     }
 
     @Test
     public void sha384Test() {
-        String actual = HashManager.hex(HashManager.sha_384(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha_384(array()));
         assertEquals(sha384sum, actual);
     }
 
     @Test
     public void sha512Test() {
-        String actual = HashManager.hex(HashManager.sha_512(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha_512(array()));
         assertEquals(sha512sum, actual);
     }
 
     @Test
     public void sha3_224Test() {
-        String actual = HashManager.hex(HashManager.sha3_224(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha3_224(array()));
         assertEquals(sha3_224sum, actual);
     }
 
     @Test
     public void sha3_256Test() {
-        String actual = HashManager.hex(HashManager.sha3_256(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha3_256(array()));
         assertEquals(sha3_256sum, actual);
     }
 
     @Test
     public void sha3_384Test() {
-        String actual = HashManager.hex(HashManager.sha3_384(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha3_384(array()));
         assertEquals(sha3_384sum, actual);
     }
 
     @Test
     public void sha3_512Test() {
-        String actual = HashManager.hex(HashManager.sha3_512(array()));
+        String actual = StringUtils.encodeHex(HashManager.sha3_512(array()));
         assertEquals(sha3_512sum, actual);
     }
 
     @Test
     public void blake2b160Test() {
-        String actual = HashManager.hex(HashManager.blake2b160(array()));
+        String actual = StringUtils.encodeHex(HashManager.blake2b160(array()));
         assertEquals(b2_160sum, actual);
     }
 
     @Test
     public void blake2b256Test() {
-        String actual = HashManager.hex(HashManager.blake2b256(array()));
+        String actual = StringUtils.encodeHex(HashManager.blake2b256(array()));
         assertEquals(b2_256sum, actual);
     }
 
     @Test
     public void blake2b384Test() {
-        String actual = HashManager.hex(HashManager.blake2b384(array()));
+        String actual = StringUtils.encodeHex(HashManager.blake2b384(array()));
         assertEquals(b2_384sum, actual);
     }
 
     @Test
     public void blake2b512Test() {
-        String actual = HashManager.hex(HashManager.blake2b512(array()));
+        String actual = StringUtils.encodeHex(HashManager.blake2b512(array()));
         assertEquals(b2_512sum, actual);
     }