EscapeXmlColumnDecorator.java

/**
 * Licensed under the Artistic License; you may not use this file
 * except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://displaytag.sourceforge.net/license.html
 *
 * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */
package org.displaytag.decorator;

import javax.servlet.jsp.PageContext;

import org.apache.commons.lang.StringEscapeUtils;
import org.displaytag.properties.MediaTypeEnum;


/**
 * This takes the string that is passed in, and escapes html tags and entities. Only operates on "html" or "xml" media.
 * @author Fabrizio Giustina
 * @version $Revision$ ($Author$)
 */
public class EscapeXmlColumnDecorator implements DisplaytagColumnDecorator
{

    /**
     * Instance used for the "escapeXml" tag attribute.
     */
    public static final DisplaytagColumnDecorator INSTANCE = new EscapeXmlColumnDecorator();

    /**
     * @see org.displaytag.decorator.DisplaytagColumnDecorator#decorate(Object, PageContext, MediaTypeEnum)
     */
    public Object decorate(Object columnValue, PageContext pageContext, MediaTypeEnum media)
    {

        if (columnValue == null || (!media.equals(MediaTypeEnum.HTML) && !media.equals(MediaTypeEnum.XML)))
        {
            return columnValue;
        }

        return StringEscapeUtils.escapeXml(columnValue.toString());
    }

}