001    // Copyright 2011 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry5.alerts;
016    
017    /**
018     * Controls how long an {@link Alert} is displayed to the end user.
019     *
020     * @since 5.3
021     */
022    public enum Duration
023    {
024        /**
025         * Transient alerts are displayed to the user, then automatically clear themselves after a few seconds. Transient alerts
026         * are not stored in the {@link AlertStorage}.
027         */
028        TRANSIENT(false),
029    
030        /**
031         * The default duration; displayed to the user a single time; once the page updates, the alert will not be presented to the
032         * user. Single duration alerts are not stored in {@link AlertStorage}.
033         */
034        SINGLE(false),
035    
036        /**
037         * For most important alerts; the alert will continue to be presented to the user until it is dismissed by the user
038         * (either by clicking on the individual alert to dismiss it, or by clicking the UI control for dismissing all alerts).
039         * Such alerts are stored persistently in {@link AlertStorage}.
040         */
041        UNTIL_DISMISSED(true);
042    
043        /**
044         * True if the alert type should persist between requests. This is only true for {@link #UNTIL_DISMISSED}.
045         */
046        public final boolean persistent;
047    
048        private Duration(boolean persistent)
049        {
050            this.persistent = persistent;
051        }
052    }