RegexFilter.java

/*
 * This file is part of "SnipSnap Radeox Rendering Engine".
 *
 * Copyright (c) 2002 Stephan J. Schmidt, Matthias L. Jugel
 * All Rights Reserved.
 *
 * Please visit http://radeox.org/ for updates and contact.
 *
 * --LICENSE NOTICE--
 * Licensed 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.
 * --LICENSE NOTICE--
 */

package org.radeox.filter.regex;

import java.util.ArrayList;
import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.radeox.filter.FilterSupport;
import org.radeox.filter.context.FilterContext;

/*
 * Class that stores regular expressions, can be subclassed for special Filters
 * @author stephan @team sonicteam
 * 
 * @version $Id: RegexFilter.java 7756 2006-04-13 12:25:49Z ian@caret.cam.ac.uk $
 */

public abstract class RegexFilter extends FilterSupport
{
	private static Log log = LogFactory.getLog(RegexFilter.class);

	protected List pattern = new ArrayList();

	protected List substitute = new ArrayList();

	public final static boolean SINGLELINE = false;

	public final static boolean MULTILINE = true;

	// TODO future use
	// private RegexService regexService;

	public RegexFilter()
	{
		super();
	}

	/**
	 * create a new regular expression that takes input as multiple lines
	 */
	public RegexFilter(String regex, String substitute)
	{
		this();
		addRegex(regex, substitute);
	}

	/**
	 * create a new regular expression and set
	 */
	public RegexFilter(String regex, String substitute, boolean multiline)
	{
		addRegex(regex, substitute, multiline);
	}

	public void clearRegex()
	{
		pattern.clear();
		substitute.clear();
	}

	public void addRegex(String regex, String substitute)
	{
		addRegex(regex, substitute, MULTILINE);
	}

	public void addRegex(String regex, String substitute, boolean multiline)
	{
		// compiler.compile(regex, (multiline ? Perl5Compiler.MULTILINE_MASK :
		// Perl5Compiler.SINGLELINE_MASK) | Perl5Compiler.READ_ONLY_MASK));
		try
		{
			org.radeox.regex.Compiler compiler = org.radeox.regex.Compiler
					.create();
			compiler.setMultiline(multiline);
			this.pattern.add(compiler.compile(regex));
			// Pattern.DOTALL
			this.substitute.add(substitute);
		}
		catch (Exception e)
		{
			log.warn("bad pattern: " + regex + " -> " + substitute + " " + e);
		}
	}

	public abstract String filter(String input, FilterContext context);
}