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.components;
016    
017    import java.text.Format;
018    
019    import org.apache.hivemind.ApplicationRuntimeException;
020    import org.apache.tapestry.AbstractComponent;
021    import org.apache.tapestry.IMarkupWriter;
022    import org.apache.tapestry.IRequestCycle;
023    
024    /**
025     * Used to insert some text (from a parameter) into the HTML. [ <a
026     * href="../../../../../ComponentReference/Insert.html">Component Reference </a>]
027     * 
028     * @author Howard Lewis Ship
029     */
030    
031    public abstract class Insert extends AbstractComponent
032    {
033        /**
034         * Prints its value parameter, possibly formatted by its format parameter.
035         */
036    
037        protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle)
038        {
039            if (cycle.isRewinding())
040                return;
041    
042            Object value = getValue();
043    
044            if (value == null)
045                return;
046    
047            String insert = null;
048    
049            Format format = getFormat();
050    
051            if (format == null)
052            {
053                insert = value.toString();
054            }
055            else
056            {
057                try
058                {
059                    insert = format.format(value);
060                }
061                catch (Exception ex)
062                {
063                    throw new ApplicationRuntimeException(ComponentMessages.unableToFormat(
064                            this,
065                            value,
066                            ex), this, getBinding("format").getLocation(), ex);
067                }
068            }
069    
070            String styleClass = getStyleClass();
071    
072            if (styleClass != null)
073            {
074                writer.begin("span");
075                writer.attribute("class", styleClass);
076    
077                renderInformalParameters(writer, cycle);
078            }
079    
080            writer.print(insert, getRaw());
081            
082            if (styleClass != null)
083                writer.end(); // <span>
084        }
085    
086        public abstract Object getValue();
087    
088        public abstract Format getFormat();
089    
090        public abstract String getStyleClass();
091    
092        public abstract boolean getRaw();
093    
094    }