/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.wicket.markup.parser;
import java.text.ParseException;
import org.apache.wicket.markup.Markup;
import org.apache.wicket.markup.MarkupElement;
/**
* Wicket uses a streaming XML parser to read the markup. A chain of IMarkupFilters is used e.g. to
* remove comments, allow for html typical markup (some tags don't need to be closed explicitly),
* etc.
*
* @see org.apache.wicket.markup.MarkupParser
* @see org.apache.wicket.markup.MarkupFactory
*
* @author Juergen Donnerstag
*/
public interface IMarkupFilter
{
/**
* IMarkupFilters are usually chained with the last filter retrieving the elements from the XML
* parser.
*
* @return The next filter in the chain, or null if the last one.
*/
IMarkupFilter getNextFilter();
/**
* Set parent filter.
*
* @param parent
* The next element in the chain
*/
void setNextFilter(final IMarkupFilter parent);
/**
* Get the next MarkupElement from the parent MarkupFilter and handle it if the specific filter
* criteria are met. Depending on the filter, it may return the MarkupElement unchanged,
* modified or remove it by asking the parent handler for the next tag.
*
* @return Return the next eligible MarkupElement. Null, if no more found.
* @throws ParseException
*/
MarkupElement nextElement() throws ParseException;
/**
* Called after all filters have been processed.
*
* @param markup
*/
void postProcess(final Markup markup);
}