GroupEventDispatcher.java 6.48 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189
/**
 * $RCSfile$
 * $Revision: 1705 $
 * $Date: 2005-07-26 14:10:33 -0300 (Tue, 26 Jul 2005) $
 *
 * Copyright (C) 2004-2005 Jive Software. All rights reserved.
 *
 * This software is published under the terms of the GNU Public License (GPL),
 * a copy of which is included in this distribution.
 */

package org.jivesoftware.wildfire.event;

import org.jivesoftware.util.Log;
import org.jivesoftware.wildfire.group.Group;

import java.util.List;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArrayList;

/**
 * Dispatches group events. Each event has a {@link EventType type}
 * and optional parameters, as follows:<p>
 *
 * <table border="1">
 * <tr><th>Event Type</th><th>Extra Params</th></tr>
 * <tr><td>{@link EventType#group_created group_created}</td><td><i>None</i></td></tr>
 * <tr><td>{@link EventType#group_deleting group_deleting}</td><td><i>None</i></td></tr>
 * <tr><td>{@link EventType#member_added member_added}</td><td>A param named <tt>member</tt> with a String username as a
 *      payload</td></tr>
 * <tr><td>{@link EventType#member_removed member_removed}</td><td>A param named <tt>member</tt> with a String username as a
 *      payload</td></tr>
 * <tr><td>{@link EventType#admin_added admin_added}</td><td>A param named <tt>admin</tt> with a String username
 *      as a payload</td></tr>
 * <tr><td>{@link EventType#admin_removed admin_removed}</td><td>A param named <tt>admin</tt> with a String username
 *      as a payload</td></tr>
 * <tr valign="top"><td>{@link EventType#group_modified group_modified}</td><td>
 * <table><tr><td><b>Reason</b></td><td><b>Key</b></td><td><b>Value</b></td></tr>
 *      <tr><td colspan="3">Name modified</td></tr>
 *      <tr><td>&nbsp;</td><td>type</td><td>nameModified</td></tr>
 *      <tr><td>&nbsp;</td><td>originalValue</td><td><i>(Name before it was modified)</i>
 * </td></tr>
 *      <tr><td colspan="3"><hr></td></tr>
 *      <tr><td colspan="3">Description modified</td></tr>
 *      <tr><td>&nbsp;</td><td>type</td><td>descriptionModified</td></tr>
 *      <tr><td>&nbsp;</td><td>originalValue</td><td><i>(Description before it was
 * modified)</i></td></tr>
 *      <tr><td colspan="3"><hr></td></tr>
 *      <tr><td colspan="3">Property modified</td></tr>
 *      <tr><td>&nbsp;</td><td>type</td><td>propertyModified</td></tr>
 *      <tr><td>&nbsp;</td><td>propertyKey</td><td><i>(Name of the property)</i></td>
 * </tr>
 *      <tr><td>&nbsp;</td><td>originalValue</td><td><i>(Property value before it was
 * modified)</i></td></tr>
 *      <tr><td colspan="3"><hr></td></tr>
 *      <tr><td colspan="3">Property added</td></tr>
 *      <tr><td>&nbsp;</td><td>type</td><td>propertyAdded</td></tr>
 *      <tr><td>&nbsp;</td><td>propertyKey</td><td><i>(Name of the new property)</i></td>
 * </tr>
 *      <tr><td colspan="3"><hr></td></tr>
 *      <tr><td colspan="3">Property deleted</td></tr>
 *      <tr><td>&nbsp;</td><td>type</td><td>propertyDeleted</td></tr>
 *      <tr><td>&nbsp;</td><td>propertyKey</td><td><i>(Name of the property deleted)</i></td></tr></table></td></tr>
 * </table>
 *
 * @author Matt Tucker
 */
public class GroupEventDispatcher {

    private static List<GroupEventListener> listeners =
            new CopyOnWriteArrayList<GroupEventListener>();

    private GroupEventDispatcher() {
        // Not instantiable.
    }

    /**
     * Registers a listener to receive events.
     *
     * @param listener the listener.
     */
    public static void addListener(GroupEventListener listener) {
        if (listener == null) {
            throw new NullPointerException();
        }
        listeners.add(listener);
    }

    /**
     * Unregisters a listener to receive events.
     *
     * @param listener the listener.
     */
    public static void removeListener(GroupEventListener listener) {
        listeners.remove(listener);
    }

    /**
     * Dispatches an event to all listeners.
     *
     * @param group the group.
     * @param eventType the event type.
     * @param params event parameters.
     */
    public static void dispatchEvent(Group group, EventType eventType, Map params) {
        for (GroupEventListener listener : listeners) {
            try {
                switch (eventType) {
                    case group_created: {
                        listener.groupCreated(group, params);
                        break;
                    }
                    case group_deleting: {
                        listener.groupDeleting(group, params);
                        break;
                    }
                    case member_added: {
                        listener.memberAdded(group, params);
                        break;
                    }
                    case member_removed: {
                        listener.memberRemoved(group, params);
                        break;
                    }
                    case admin_added: {
                        listener.adminAdded(group, params);
                        break;
                    }
                    case admin_removed: {
                        listener.adminRemoved(group, params);
                        break;
                    }
                    case group_modified: {
                        listener.groupModified(group, params);
                        break;
                    }
                    default:
                        break;
                }
            }
            catch (Exception e) {
                Log.error(e);
            }
        }
    }

    /**
     * Represents valid event types.
     */
    public enum EventType {

        /**
         * A new group was created.
         */
        group_created,

        /**
         * A group is about to be deleted. Note that this event is fired before
         * a group is actually deleted. This allows for referential cleanup
         * before the group is gone.
         */
        group_deleting,

        /**
         * The name, description, or extended property of a group was changed.
         */
        group_modified,

        /**
         * A member was added to a group.
         */
        member_added,

        /**
         * A member was removed from a group.
         */
        member_removed,

        /**
         * An administrator was added to a group.
         */
        admin_added,

        /**
         * An administrator was removed from a group.
         */
        admin_removed;
    }
}