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.ApplicationRuntimeException;
018    import org.apache.hivemind.HiveMind;
019    import org.apache.tapestry.AbstractComponent;
020    import org.apache.tapestry.IMarkupWriter;
021    import org.apache.tapestry.IRequestCycle;
022    import org.apache.tapestry.Tapestry;
023    
024    /**
025     * A deck contains a collection of cards. There is a variety of card types, each specifying a
026     * different mode of user interaction.
027     * 
028     * @author David Solis
029     * @since 3.0
030     */
031    
032    public abstract class Card extends AbstractComponent
033    {
034        private static final String ATTRIBUTE_NAME = "org.apache.tapestry.wml.Card";
035    
036        /**
037         * @see AbstractComponent#renderComponent(IMarkupWriter, IRequestCycle)
038         */
039    
040        protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle)
041        {
042            if (cycle.getAttribute(ATTRIBUTE_NAME) != null)
043                throw new ApplicationRuntimeException(Tapestry.getMessage("Card.cards-may-not-nest"),
044                        this, null, null);
045    
046            cycle.setAttribute(ATTRIBUTE_NAME, this);
047    
048            writer.begin("card");
049    
050            String title = getTitle();
051            if (HiveMind.isNonBlank(title))
052                writer.attribute("title", title);
053    
054            renderInformalParameters(writer, cycle);
055    
056            IMarkupWriter nestedWriter = writer.getNestedWriter();
057    
058            renderBody(nestedWriter, cycle);
059    
060            nestedWriter.close();
061    
062            writer.end();
063    
064            cycle.removeAttribute(ATTRIBUTE_NAME);
065        }
066    
067        public abstract String getTitle();
068    }