diff a/test/jdk/sun/security/ec/xec/XECKeyFormat.java b/test/jdk/sun/security/ec/xec/XECKeyFormat.java
--- a/test/jdk/sun/security/ec/xec/XECKeyFormat.java
+++ b/test/jdk/sun/security/ec/xec/XECKeyFormat.java
@@ -24,11 +24,10 @@
 /*
  * @test
  * @bug 8213363
  * @summary Check for correct formatting of X25519/X448 private keys
  * @library /test/lib
- * @build jdk.test.lib.Convert
  * @modules java.base/sun.security.util
  * @run main XECKeyFormat
  */
 
 import java.security.*;
@@ -37,11 +36,11 @@
 import java.io.*;
 import java.nio.file.*;
 import java.math.*;
 import java.util.*;
 
-import jdk.test.lib.Convert;
+import java.util.Hex;
 
 import sun.security.util.*;
 
 public class XECKeyFormat {
 
@@ -96,11 +95,11 @@
         }
     }
 
     private static void pubKeyTest(Provider p, String key) throws Exception {
         // ensure that a properly-formatted key can be read
-        byte[] encodedKey = Convert.hexStringToByteArray(key);
+        byte[] encodedKey = Hex.decoder().decode(key);
         X509EncodedKeySpec keySpec = new X509EncodedKeySpec(encodedKey);
         KeyFactory kf = KeyFactory.getInstance("XDH", p);
         kf.generatePublic(keySpec);
     }
 
@@ -123,11 +122,11 @@
         PKCS8EncodedKeySpec keySpec =
             kf.getKeySpec(priv, PKCS8EncodedKeySpec.class);
         checkPrivKeyFormat(keySpec.getEncoded());
 
         // ensure that a properly-formatted key can be read
-        byte[] encodedKey = Convert.hexStringToByteArray(privKeys.get(algName));
+        byte[] encodedKey = Hex.decoder().decode(privKeys.get(algName));
         keySpec = new PKCS8EncodedKeySpec(encodedKey);
         kf.generatePrivate(keySpec);
     }
 
     private static void checkPrivKeyFormat(byte[] key) throws IOException {