--- /dev/null	2020-01-02 04:43:18.583999853 +0000
+++ new/test/lib/jdk/test/lib/Convert.java	2020-01-30 06:38:08.803704871 +0000
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.test.lib;
+
+import java.math.BigInteger;
+
+/**
+ * Utility class containing conversions between strings, arrays, and numeric
+ * values.
+ */
+
+public class Convert {
+
+    // Convert from a byte array to a hexadecimal representation as a string.
+    public static String byteArrayToHexString(byte[] arr) {
+        StringBuilder result = new StringBuilder();
+        for (int i = 0; i < arr.length; ++i) {
+            byte curVal = arr[i];
+            result.append(Character.forDigit(curVal >> 4 & 0xF, 16));
+            result.append(Character.forDigit(curVal & 0xF, 16));
+        }
+        return result.toString();
+    }
+
+    // Expand a single byte to a byte array
+    public static byte[] byteToByteArray(byte v, int length) {
+        byte[] result = new byte[length];
+        result[0] = v;
+        return result;
+    }
+
+    // Convert a hexadecimal string to a byte array
+    public static byte[] hexStringToByteArray(String str) {
+        byte[] result = new byte[str.length() / 2];
+        for (int i = 0; i < result.length; i++) {
+            result[i] = (byte) Character.digit(str.charAt(2 * i), 16);
+            result[i] <<= 4;
+            result[i] += Character.digit(str.charAt(2 * i + 1), 16);
+        }
+        return result;
+    }
+
+    /*
+     * Convert a hexadecimal string to the corresponding little-ending number
+     * as a BigInteger. The clearHighBit argument determines whether the most
+     * significant bit of the highest byte should be set to 0 in the result.
+     */
+    public static
+    BigInteger hexStringToBigInteger(boolean clearHighBit, String str) {
+        BigInteger result = BigInteger.ZERO;
+        for (int i = 0; i < str.length() / 2; i++) {
+            int curVal = Character.digit(str.charAt(2 * i), 16);
+            curVal <<= 4;
+            curVal += Character.digit(str.charAt(2 * i + 1), 16);
+            if (clearHighBit && i == str.length() / 2 - 1) {
+                curVal &= 0x7F;
+            }
+            result = result.add(BigInteger.valueOf(curVal).shiftLeft(8 * i));
+        }
+        return result;
+    }
+}
+
+