--- a/src/share/classes/javax/management/MBeanAttributeInfo.java	Wed Sep 11 17:07:35 2013 -0700
+++ b/src/share/classes/javax/management/MBeanAttributeInfo.java	Fri Sep 13 10:48:12 2013 +0200
@@ -30,6 +30,7 @@
 
 import com.sun.jmx.mbeanserver.GetPropertyAction;
 import com.sun.jmx.mbeanserver.Introspector;
+import java.util.Objects;
 
 
 /**
@@ -301,7 +302,7 @@
        right and we needlessly hashed in the description and parameter
        array.  */
     public int hashCode() {
-        return getName().hashCode() ^ getType().hashCode();
+        return Objects.hash(getName(), getType());
     }
 
     private static boolean isIs(Method getter) {

--- a/src/share/classes/javax/management/MBeanConstructorInfo.java	Wed Sep 11 17:07:35 2013 -0700
+++ b/src/share/classes/javax/management/MBeanConstructorInfo.java	Fri Sep 13 10:48:12 2013 +0200
@@ -29,6 +29,7 @@
 import java.lang.annotation.Annotation;
 import java.lang.reflect.Constructor;
 import java.util.Arrays;
+import java.util.Objects;
 
 /**
  * Describes a constructor exposed by an MBean.  Instances of this
@@ -203,11 +204,7 @@
        quite long and yet the same between constructors.  Likewise for
        the descriptor.  */
     public int hashCode() {
-        int hash = getName().hashCode();
-        MBeanParameterInfo[] sig = fastGetSignature();
-        for (int i = 0; i < sig.length; i++)
-            hash ^= sig[i].hashCode();
-        return hash;
+        return Objects.hash(getName()) ^ Arrays.hashCode(fastGetSignature());
     }
 
     private static MBeanParameterInfo[] constructorSignature(Constructor<?> cn) {

--- a/src/share/classes/javax/management/MBeanInfo.java	Wed Sep 11 17:07:35 2013 -0700
+++ b/src/share/classes/javax/management/MBeanInfo.java	Fri Sep 13 10:48:12 2013 +0200
@@ -36,6 +36,7 @@
 import java.util.WeakHashMap;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
+import java.util.Objects;
 
 import static javax.management.ImmutableDescriptor.nonNullDescriptor;
 
@@ -515,24 +516,15 @@
         if (hashCode != 0)
             return hashCode;
 
-        hashCode =
-            getClassName().hashCode() ^
-            getDescriptor().hashCode() ^
-            arrayHashCode(fastGetAttributes()) ^
-            arrayHashCode(fastGetOperations()) ^
-            arrayHashCode(fastGetConstructors()) ^
-            arrayHashCode(fastGetNotifications());
+        hashCode = Objects.hash(getClassName(), getDescriptor())
+                ^ Arrays.hashCode(fastGetAttributes())
+                ^ Arrays.hashCode(fastGetOperations())
+                ^ Arrays.hashCode(fastGetConstructors())
+                ^ Arrays.hashCode(fastGetNotifications());
 
         return hashCode;
     }
 
-    private static int arrayHashCode(Object[] array) {
-        int hash = 0;
-        for (int i = 0; i < array.length; i++)
-            hash ^= array[i].hashCode();
-        return hash;
-    }
-
     /**
      * Cached results of previous calls to arrayGettersSafe.  This is
      * a WeakHashMap so that we don't prevent a class from being

--- a/src/share/classes/javax/management/MBeanOperationInfo.java	Wed Sep 11 17:07:35 2013 -0700
+++ b/src/share/classes/javax/management/MBeanOperationInfo.java	Fri Sep 13 10:48:12 2013 +0200
@@ -29,6 +29,7 @@
 import java.lang.annotation.Annotation;
 import java.lang.reflect.Method;
 import java.util.Arrays;
+import java.util.Objects;
 
 /**
  * Describes a management operation exposed by an MBean.  Instances of
@@ -309,7 +310,7 @@
        parameter array.  */
     @Override
     public int hashCode() {
-        return getName().hashCode() ^ getReturnType().hashCode();
+        return Objects.hash(getName(), getReturnType());
     }
 
     private static MBeanParameterInfo[] methodSignature(Method method) {

--- a/src/share/classes/javax/management/MBeanParameterInfo.java	Wed Sep 11 17:07:35 2013 -0700
+++ b/src/share/classes/javax/management/MBeanParameterInfo.java	Fri Sep 13 10:48:12 2013 +0200
@@ -25,6 +25,7 @@
 
 package javax.management;
 
+import java.util.Objects;
 
 /**
  * Describes an argument of an operation exposed by an MBean.
@@ -143,6 +144,6 @@
     }
 
     public int hashCode() {
-        return getName().hashCode() ^ getType().hashCode();
+        return Objects.hash(getName(), getType());
     }
 }

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/javax/management/MBeanInfo/MBeanInfoHashCodeNPETest.java	Fri Sep 13 10:48:12 2013 +0200
@@ -0,0 +1,176 @@
+/*
+ * Copyright (c) 2013, 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.
+ */
+
+import javax.management.MBeanAttributeInfo;
+import javax.management.MBeanConstructorInfo;
+import javax.management.MBeanInfo;
+import javax.management.MBeanNotificationInfo;
+import javax.management.MBeanOperationInfo;
+import javax.management.MBeanParameterInfo;
+import javax.management.modelmbean.DescriptorSupport;
+import javax.management.openmbean.SimpleType;
+
+/*
+ * @test
+ * @bug 8023669
+ * @summary Test that hashCode()throws NullPointerException
+ * @author Shanliang JIANG
+ * @run clean MBeanInfoHashCodeNPETest
+ * @run build MBeanInfoHashCodeNPETest
+ * @run main MBeanInfoHashCodeNPETest
+ */
+public class MBeanInfoHashCodeNPETest {
+    private static int failed = 0;
+
+    public static void main(String[] args) throws Exception {
+        System.out.println("---MBeanInfoHashCodeNPETest-main ...");
+
+        // ----
+        System.out.println("\n---Testing on MBeanAttributeInfo...");
+        MBeanAttributeInfo mbeanAttributeInfo = new MBeanAttributeInfo(
+                null, SimpleType.INTEGER.getClassName(), "description", true, true, false);
+        test(mbeanAttributeInfo, "class name");
+
+        mbeanAttributeInfo = new MBeanAttributeInfo(
+                "name", null, "description", true, true, false);
+        test(mbeanAttributeInfo, "type");
+
+        mbeanAttributeInfo = new MBeanAttributeInfo(
+                "name", SimpleType.INTEGER.getClassName(), null, true, true, false);
+        test(mbeanAttributeInfo, "description");
+
+        // ----
+        System.out.println("\n---Testing on MBeanConstructorInfo...");
+        MBeanConstructorInfo mbeanConstructorInfo = new MBeanConstructorInfo(
+                null, "", new MBeanParameterInfo[]{}, new DescriptorSupport());
+        test(mbeanConstructorInfo, "name");
+
+        mbeanConstructorInfo = new MBeanConstructorInfo(
+                "", null, new MBeanParameterInfo[]{}, new DescriptorSupport());
+        test(mbeanConstructorInfo, "description");
+
+        mbeanConstructorInfo = new MBeanConstructorInfo(
+                "", "", null, new DescriptorSupport());
+        test(mbeanConstructorInfo, "MBeanParameterInfo");
+
+        mbeanConstructorInfo = new MBeanConstructorInfo(
+                "", "", new MBeanParameterInfo[]{}, null);
+        test(mbeanConstructorInfo, "descriptor");
+
+        // ----
+        System.out.println("\n---Testing on MBeanOperationInfo...");
+        MBeanOperationInfo mbeanOperationInfo = new MBeanOperationInfo(
+                null, "description", new MBeanParameterInfo[]{}, "type", 1, new DescriptorSupport());
+        test(mbeanOperationInfo, "name");
+
+        mbeanOperationInfo = new MBeanOperationInfo(
+                "name", null, new MBeanParameterInfo[]{}, "type", 1, new DescriptorSupport());
+        test(mbeanOperationInfo, "description");
+
+        mbeanOperationInfo = new MBeanOperationInfo(
+                "name", "description", null, "type", 1, new DescriptorSupport());
+        test(mbeanOperationInfo, "MBeanParameterInfo");
+
+        mbeanOperationInfo = new MBeanOperationInfo(
+                "name", "description", new MBeanParameterInfo[]{}, null, 1, new DescriptorSupport());
+        test(mbeanOperationInfo, "type");
+
+        mbeanOperationInfo = new MBeanOperationInfo(
+                "name", "description", new MBeanParameterInfo[]{}, "type", -1, new DescriptorSupport());
+        test(mbeanOperationInfo, "native impact");
+
+        mbeanOperationInfo = new MBeanOperationInfo(
+                "name", "description", new MBeanParameterInfo[]{}, "type", 1, null);
+        test(mbeanOperationInfo, "Descriptor");
+
+        // ----
+        System.out.println("\n---Testing on MBeanParameterInfo...");
+        MBeanParameterInfo mbeanParameterInfo = new MBeanParameterInfo(
+                null, "type", "description", new DescriptorSupport());
+        test(mbeanParameterInfo, "name");
+
+        mbeanParameterInfo = new MBeanParameterInfo(
+                "name", null, "description", new DescriptorSupport());
+        test(mbeanParameterInfo, "description");
+
+        mbeanParameterInfo = new MBeanParameterInfo(
+                "name", "type", null, new DescriptorSupport());
+        test(mbeanParameterInfo, "description");
+
+        mbeanParameterInfo = new MBeanParameterInfo(
+                "name", "type", "description", null);
+        test(mbeanParameterInfo, "Descriptor");
+
+        // ----
+        System.out.println("\n---Testing on MBeanInfo...");
+        String className = "toto";
+        String description = "titi";
+        MBeanAttributeInfo[] attrInfos = new MBeanAttributeInfo[]{};
+        MBeanConstructorInfo[] constrInfos = new MBeanConstructorInfo[]{};
+        MBeanOperationInfo[] operaInfos = new MBeanOperationInfo[]{};
+        MBeanNotificationInfo[] notifInfos = new MBeanNotificationInfo[]{};
+
+        MBeanInfo minfo = new MBeanInfo(null, description, attrInfos, constrInfos, operaInfos, notifInfos);
+        test(minfo, "class name");
+
+        minfo = new MBeanInfo(className, description, attrInfos, constrInfos, operaInfos, notifInfos);
+        test(minfo, "name");
+
+        minfo = new MBeanInfo(className, null, attrInfos, constrInfos, operaInfos, notifInfos);
+        test(minfo, "description");
+
+        minfo = new MBeanInfo(className, description, null, constrInfos, operaInfos, notifInfos);
+        test(minfo, "attrInfos");
+
+        minfo = new MBeanInfo(className, description, attrInfos, constrInfos, null, notifInfos);
+        test(minfo, "operaInfos");
+
+        minfo = new MBeanInfo(className, description, attrInfos, constrInfos, operaInfos, null);
+        test(minfo, "notifInfos");
+
+        Thread.sleep(100);
+        if (failed > 0) {
+            throw new RuntimeException("Test failed: "+failed);
+        } else {
+            System.out.println("---Test: PASSED");
+        }
+    }
+
+    private static void test(Object obj, String param) {
+        try {
+            obj.hashCode();
+            System.out.println("OK: "+obj.getClass().getSimpleName()+".hashCode worked with a null "+param);
+        } catch (NullPointerException npe) {
+            System.out.println("--->KO!!! "+obj.getClass().getSimpleName()+".hashCode got NPE with a null "+param);
+            failed++;
+        }
+
+        try {
+            obj.toString();
+            System.out.println("OK: "+obj.getClass().getSimpleName()+".toString worked with a null "+param);
+        } catch (NullPointerException npe) {
+            System.out.println("--->KO!!! "+obj.getClass().getSimpleName()+".toString got NPE.");
+            failed++;
+        }
+    }
+}