6917791: KeyTabEntry, when the byte value smaller then 16, the string drop '0'

Reviewed-by: xuelei

jdk/src/share/classes/sun/security/krb5/internal/ktab/KeyTabEntry.java

@@ -75,7 +75,7 @@ public class KeyTabEntry implements KeyTabConstants {
     public String getKeyString() {
         StringBuffer sb = new StringBuffer("0x");
         for (int i = 0; i < keyblock.length; i++) {
-            sb.append(Integer.toHexString(keyblock[i]&0xff));
+            sb.append(String.format("%02x", keyblock[i]&0xff));
         }
         return sb.toString();
     }

jdk/test/sun/security/krb5/ktab/KeyString.java

+/*
+ * Copyright 2010 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+/*
+ * @test
+ * @bug 6917791
+ * @summary KeyTabEntry, when the byte value smaller then 16, the string drop '0'
+ */
+
+import sun.security.krb5.internal.ktab.KeyTabEntry;
+
+public class KeyString {
+    public static void main(String[] args) throws Exception {
+        KeyTabEntry e = new KeyTabEntry(null, null, null, 1, 1, new byte[8]);
+        // "0x" plus eight "00"
+        if (e.getKeyString().length() != 18) {
+            throw new Exception("key bytes length not correct");
+        }
+    }
+}