/**
* This file is part of Jahia, next-generation open source CMS:
* Jahia's next-generation, open source CMS stems from a widely acknowledged vision
* of enterprise application convergence - web, search, document, social and portal -
* unified by the simplicity of web content management.
*
* For more information, please visit http://www.jahia.com.
*
* Copyright (C) 2002-2011 Jahia Solutions Group SA. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* As a special exception to the terms and conditions of version 2.0 of
* the GPL (or any later version), you may redistribute this Program in connection
* with Free/Libre and Open Source Software ("FLOSS") applications as described
* in Jahia's FLOSS exception. You should have received a copy of the text
* describing the FLOSS exception, and it is also available here:
* http://www.jahia.com/license
*
* Commercial and Supported Versions of the program (dual licensing):
* alternatively, commercial and supported versions of the program may be used
* in accordance with the terms and conditions contained in a separate
* written agreement between you and Jahia Solutions Group SA.
*
* If you are unsure which license is appropriate for your use,
* please contact the sales department at sales@jahia.com.
*/
package org.jahia.services.render.filter;
import java.util.List;
import java.util.Map;
import java.util.Set;
import net.htmlparser.jericho.Attribute;
import net.htmlparser.jericho.Attributes;
import net.htmlparser.jericho.OutputDocument;
import net.htmlparser.jericho.Source;
import net.htmlparser.jericho.StartTag;
import org.jahia.services.render.RenderContext;
import org.jahia.services.render.Resource;
/**
* Traverses the configured HTML tag attributes of the provided document and
* executes visitors to modify attribute values.
*
* @author Sergiy Shyrkov
*/
public class HtmlTagAttributeTraverser {
/**
* Defines visitor for modifying an HTML tag attribute, found in the
* content.
*
* @author Sergiy Shyrkov
*/
public static interface HtmlTagAttributeVisitor {
/**
* Applies the required modifications to the specified attribute if
* needed.
*
* @param value the attribute value to be modified
* @param context current rendering context
* @param resource current resource
* @returns the modified attribute value
*/
String visit(String value, RenderContext context, Resource resource);
}
private Map<String, Set<String>> attributesToVisit;
/**
* Initializes an instance of this class.
*
* @param attributesToVisit a map of tags and attributes to visit
*/
public HtmlTagAttributeTraverser(Map<String, Set<String>> attributesToVisit) {
super();
this.attributesToVisit = attributesToVisit;
}
/**
* Parses the provided HTML content and calls specified visitors to modify
* the value of matching tag attributes. Returns modified content as a
* result.
*
* @param htmlContent the source content to be modified
* @param visitors visitors to be called for matching attributes
* @return modified content as a result
*/
public String traverse(String htmlContent, HtmlTagAttributeVisitor... visitors) {
return traverse(htmlContent, null, null, visitors);
}
/**
* Parses the provided HTML content and calls specified visitors to modify
* the value of matching tag attributes. Returns modified content as a
* result.
*
* @param htmlContent the source content to be modified
* @param context current rendering context
* @param resource current resource
* @param visitors visitors to be called for matching attributes
* @return modified content as a result
*/
public String traverse(String htmlContent, RenderContext context, Resource resource,
HtmlTagAttributeVisitor... visitors) {
if (attributesToVisit == null || attributesToVisit.isEmpty() || visitors == null || visitors.length == 0) {
return htmlContent;
}
Source source = new Source(htmlContent);
OutputDocument document = new OutputDocument(source);
for (Map.Entry<String, Set<String>> tag : attributesToVisit.entrySet()) {
List<StartTag> tags = source.getAllStartTags(tag.getKey());
for (StartTag startTag : tags) {
final Attributes attributes = startTag.getAttributes();
for (String attrName : tag.getValue()) {
Attribute attribute = attributes.get(attrName);
if (attribute != null) {
String originalValue = attribute.getValue();
String value = originalValue;
for (HtmlTagAttributeVisitor visitor : visitors) {
value = visitor.visit(value, context, resource);
}
if (originalValue != value && originalValue != null && !originalValue.equals(value)) {
document.replace(attribute.getValueSegment(), value);
}
}
}
}
}
return document.toString();
}
}