Remove unnecessary call to MessageDigest.reset

Author: jasontedor

core/src/main/java/org/elasticsearch/common/hash/MessageDigests.java

@@ -41,23 +41,20 @@ public class MessageDigests {
     }
 
     public static MessageDigest md5() {
-        return cloneAndReset(MD5_DIGEST);
+        return clone(MD5_DIGEST);
     }
 
-
     public static MessageDigest sha1() {
-        return cloneAndReset(SHA_1_DIGEST);
+        return clone(SHA_1_DIGEST);
     }
 
     public static MessageDigest sha256() {
-        return cloneAndReset(SHA_256_DIGEST);
+        return clone(SHA_256_DIGEST);
     }
 
-    private static MessageDigest cloneAndReset(MessageDigest messageDigest) {
+    private static MessageDigest clone(MessageDigest messageDigest) {
         try {
-            MessageDigest clone = (MessageDigest) messageDigest.clone();
-            clone.reset();
-            return clone;
+            return (MessageDigest) messageDigest.clone();
         } catch (CloneNotSupportedException e) {
             throw new ElasticsearchException("Unexpected exception cloning MessageDigest instance", e);
         }

core/src/test/java/org/elasticsearch/common/hash/MessageDigestsTests.java

@@ -70,7 +70,7 @@ public void testToHexString() throws Exception {
             BigInteger expected = BigInteger.probablePrime(256, random());
             byte[] bytes = expected.toByteArray();
             String hex = MessageDigests.toHexString(bytes);
-            String zeros = new String(new char[bytes.length * 2]).replace("\0", "0");
+            String zeros = new String(new char[2 * bytes.length]).replace("\0", "0");
             String expectedAsString = expected.toString(16);
             String expectedHex = zeros.substring(expectedAsString.length()) + expectedAsString;
             assertEquals(expectedHex, hex);