diff --git a/src/share/classes/javax/lang/model/type/MirroredTypeException.java b/src/share/classes/javax/lang/model/type/MirroredTypeException.java
index db729c59550ccf3c035f331050893534c3cf722c..543ef9d922c4c89d108a93c979baad368f90f96b 100644
--- a/src/share/classes/javax/lang/model/type/MirroredTypeException.java
+++ b/src/share/classes/javax/lang/model/type/MirroredTypeException.java
@@ -54,7 +54,7 @@ public class MirroredTypeException extends RuntimeException {
      * @param type  the type being accessed
      */
     public MirroredTypeException(TypeMirror type) {
-        super("Attempt to access Class object for TypeMirror " + type);
+        super("Attempt to access Class object for TypeMirror " + type.toString());
         this.type = type;
     }
 
diff --git a/test/tools/javac/processing/model/type/MirroredTypeEx/NpeTest.java b/test/tools/javac/processing/model/type/MirroredTypeEx/NpeTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..b675089dd2bc6e15791728454af5d1c6bdd9e772
--- /dev/null
+++ b/test/tools/javac/processing/model/type/MirroredTypeEx/NpeTest.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright 2009 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     6593082
+ * @summary MirroredTypeException constructor should not accept null
+ * @author  Joseph D. Darcy
+ */
+
+import javax.lang.model.type.*;
+
+public class NpeTest  {
+    public static void main(String... args) {
+        try {
+            MirroredTypeException mte = new MirroredTypeException(null);
+            throw new RuntimeException("Expected NPE not thrown.");
+        } catch (NullPointerException npe) {
+            ; // success
+        }
+    }
+}