package com.sun.org.apache.regexp.internal;

/*
 * ====================================================================
 * 
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:  
 *       "This product includes software developed by the 
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Jakarta-Regexp", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
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 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */ 

/**
 * This is a class that contains utility helper methods for this package.
 *
 * @author <a href="mailto:jonl@muppetlabs.com">Jonathan Locke</a>
 * @version $Id: REUtil.java,v 1.2 2000/04/30 20:42:35 jon Exp $
 */
public class REUtil
{
    /** complex: */
    private static final String complexPrefix = "complex:";
    
    /**
     * Creates a regular expression, permitting simple or complex syntax 
     * @param expression The expression, beginning with a prefix if it's complex or 
     * having no prefix if it's simple
     * @param matchFlags Matching style flags
     * @return The regular expression object
     * @exception RESyntaxException thrown in case of error
     */
    public static RE createRE(String expression, int matchFlags) throws RESyntaxException
    {
        if (expression.startsWith(complexPrefix))
        {
            return new RE(expression.substring(complexPrefix.length()), matchFlags);
        }
        return new RE(RE.simplePatternToFullRegularExpression(expression), matchFlags);
    }

    /**
     * Creates a regular expression, permitting simple or complex syntax 
     * @param expression The expression, beginning with a prefix if it's complex or 
     * having no prefix if it's simple 
     * @return The regular expression object
     * @exception RESyntaxException thrown in case of error
     */
    public static RE createRE(String expression) throws RESyntaxException
    {
        return createRE(expression, RE.MATCH_NORMAL);
    }
}