/*

 * Copyright 1999-2006 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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * 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.

 */

package javax.management;

import java.util.Arrays;

/**

 * <p>The <CODE>MBeanNotificationInfo</CODE> class is used to describe the

 * characteristics of the different notification instances

 * emitted by an MBean, for a given Java class of notification.

 * If an MBean emits notifications that can be instances of different Java classes,

 * then the metadata for that MBean should provide an <CODE>MBeanNotificationInfo</CODE>

 * object for each of these notification Java classes.</p>

 *

 * <p>Instances of this class are immutable.  Subclasses may be

 * mutable but this is not recommended.</p>

 *

 * <p>This class extends <CODE>javax.management.MBeanFeatureInfo</CODE>

 * and thus provides <CODE>name</CODE> and <CODE>description</CODE> fields.

 * The <CODE>name</CODE> field should be the fully qualified Java class name of

 * the notification objects described by this class.</p>

 *

 * <p>The <CODE>getNotifTypes</CODE> method returns an array of

 * strings containing the notification types that the MBean may

 * emit. The notification type is a dot-notation string which

 * describes what the emitted notification is about, not the Java

 * class of the notification.  A single generic notification class can

 * be used to send notifications of several types.  All of these types

 * are returned in the string array result of the

 * <CODE>getNotifTypes</CODE> method.

 *

 * @since 1.5

 */

public class MBeanNotificationInfo extends MBeanFeatureInfo implements Cloneable {

    /* Serial version */

    static final long serialVersionUID = -3888371564530107064L;

    private static final String[] NO_TYPES = new String[0];

    static final MBeanNotificationInfo[] NO_NOTIFICATIONS =

        new MBeanNotificationInfo[0];

    /**

     * @serial The different types of the notification.

     */

    private final String[] types;

    /** @see MBeanInfo#arrayGettersSafe */

    private final transient boolean arrayGettersSafe;

    /**

     * Constructs an <CODE>MBeanNotificationInfo</CODE> object.

     *

     * @param notifTypes The array of strings (in dot notation)

     * containing the notification types that the MBean may emit.

     * This may be null with the same effect as a zero-length array.

     * @param name The fully qualified Java class name of the

     * described notifications.

     * @param description A human readable description of the data.

     */

    public MBeanNotificationInfo(String[] notifTypes,

                                 String name,

                                 String description) {

        this(notifTypes, name, description, null);

    }

    /**

     * Constructs an <CODE>MBeanNotificationInfo</CODE> object.

     *

     * @param notifTypes The array of strings (in dot notation)

     * containing the notification types that the MBean may emit.

     * This may be null with the same effect as a zero-length array.

     * @param name The fully qualified Java class name of the

     * described notifications.

     * @param description A human readable description of the data.

     * @param descriptor The descriptor for the notifications.  This may be null

     * which is equivalent to an empty descriptor.

     *

     * @since 1.6

     */

    public MBeanNotificationInfo(String[] notifTypes,

                                 String name,

                                 String description,

                                 Descriptor descriptor) {

        super(name, description, descriptor);

        /* We do not validate the notifTypes, since the spec just says

           they are dot-separated, not that they must look like Java

           classes.  E.g. the spec doesn't forbid "sun.prob.25" as a

           notifType, though it doesn't explicitly allow it

           either.  */

        if (notifTypes == null)

            notifTypes = NO_TYPES;

        this.types = notifTypes;

        this.arrayGettersSafe =

            MBeanInfo.arrayGettersSafe(this.getClass(),

                                       MBeanNotificationInfo.class);

    }

    /**

     * Returns a shallow clone of this instance.

     * The clone is obtained by simply calling <tt>super.clone()</tt>,

     * thus calling the default native shallow cloning mechanism

     * implemented by <tt>Object.clone()</tt>.

     * No deeper cloning of any internal field is made.

     */

     public Object clone () {

         try {

             return super.clone() ;

         } catch (CloneNotSupportedException e) {

             // should not happen as this class is cloneable

             return null;

         }

     }

    /**

     * Returns the array of strings (in dot notation) containing the

     * notification types that the MBean may emit.

     *

     * @return the array of strings.  Changing the returned array has no

     * effect on this MBeanNotificationInfo.

     */

    public String[] getNotifTypes() {

        if (types.length == 0)

            return NO_TYPES;

        else

            return types.clone();

    }

    private String[] fastGetNotifTypes() {

        if (arrayGettersSafe)

            return types;

        else

            return getNotifTypes();

    }

    public String toString() {

        return

            getClass().getName() + "[" +

            "description=" + getDescription() + ", " +

            "name=" + getName() + ", " +

            "notifTypes=" + Arrays.asList(fastGetNotifTypes()) + ", " +

            "descriptor=" + getDescriptor() +

            "]";

    }

    /**

     * Compare this MBeanNotificationInfo to another.

     *

     * @param o the object to compare to.

     *

     * @return true if and only if <code>o</code> is an MBeanNotificationInfo

     * such that its {@link #getName()}, {@link #getDescription()},

     * {@link #getDescriptor()},

     * and {@link #getNotifTypes()} values are equal (not necessarily

     * identical) to those of this MBeanNotificationInfo.  Two

     * notification type arrays are equal if their corresponding

     * elements are equal.  They are not equal if they have the same

     * elements but in a different order.

     */

    public boolean equals(Object o) {

        if (o == this)

            return true;

        if (!(o instanceof MBeanNotificationInfo))

            return false;

        MBeanNotificationInfo p = (MBeanNotificationInfo) o;

        return (p.getName().equals(getName()) &&

                p.getDescription().equals(getDescription()) &&

                p.getDescriptor().equals(getDescriptor()) &&

                Arrays.equals(p.fastGetNotifTypes(), fastGetNotifTypes()));

    }

    public int hashCode() {

        int hash = getName().hashCode();

        for (int i = 0; i < types.length; i++)

            hash ^= types[i].hashCode();

        return hash;

    }

}