001    // Copyright 2004, 2005 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.tapestry.wml;
016    
017    import org.apache.hivemind.HiveMind;
018    import org.apache.tapestry.AbstractComponent;
019    import org.apache.tapestry.IMarkupWriter;
020    import org.apache.tapestry.IRequestCycle;
021    
022    /**
023     * The Timer element declares a card timer, which exposes a means of processing inactivity or idle
024     * time. The timer is initialised and started at card entry and is stopped when the card is exited.
025     * 
026     * @author David Solis
027     * @since 3.0
028     */
029    
030    public abstract class Timer extends AbstractComponent
031    {
032        /**
033         * @see AbstractComponent#renderComponent(IMarkupWriter, IRequestCycle)
034         */
035    
036        protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle)
037        {
038            boolean render = !cycle.isRewinding();
039    
040            if (render)
041            {
042                writer.beginEmpty("timer");
043    
044                writer.attribute("name", getName());
045    
046                String value = getValue();
047                if (HiveMind.isNonBlank(value))
048                    writer.attribute("value", value);
049                else
050                    writer.attribute("value", "0");
051    
052                renderInformalParameters(writer, cycle);
053    
054                writer.closeTag();
055            }
056        }
057    
058        public abstract String getName();
059    
060        /** @since 4.0 */
061    
062        public abstract String getValue();
063    }