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 * without modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain copyright statements and notices. Redistributions
 * must also contain a copy of this document.
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 * conditions and the following disclaimer in the documentation and/or other materials provided with
 * the distribution.
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 * without prior written permission of Intalio, Inc. For written permission, please contact
 * info@exolab.org.
 *
 * 4. Products derived from this Software may not be called "Exolab" nor may "Exolab" appear in
 * their names without prior written permission of Intalio, Inc. Exolab is a registered trademark of
 * Intalio, Inc.
 *
 * 5. Due credit should be given to the Exolab Project (http://www.exolab.org/).
 *
 * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Copyright 2000-2002 (C) Intalio, Inc. All Rights Reserved.
 *
 * $Id$
 */

package org.exolab.castor.util;

import org.apache.oro.text.regex.*;

/**
 * An implementation of the RegExpEvaluator that uses the Jakarta ORO Regular Expression library.
 * For more information about the Jakarta ORO library please visit:
 * <a href="http://jakarta.apache.org/oro/"> http://jakarta.apache.org/oro/</a>
 *
 * @author <a href="mailto:glenn@voyager.apg.more.net">Glenn Nielsen</a>
 * @author <a href="mailto:kvisco@intalio.com">Keith Visco</a>
 * @version $Revision$ $Date: 2003-03-03 00:05:44 -0700 (Mon, 03 Mar 2003) $
 **/
public class JakartaOroEvaluator implements RegExpEvaluator {

  private static final String BOL = "^";
  private static final String EOL = "$";

  /**
   * The Regular expression
   **/
  private Perl5Pattern _regexp = null;

  /**
   * Sets the regular expression to match against during a call to #matches
   *
   * @param rexpr the regular expression
   **/
  public void setExpression(String rexpr) {

    if (rexpr != null) {
      try {
        // -- patch and compile expression
        Perl5Compiler compiler = new Perl5Compiler();
        _regexp = (Perl5Pattern) compiler.compile(BOL + rexpr + EOL, Perl5Compiler.SINGLELINE_MASK);
      } catch (MalformedPatternException ex) {
        String err = "RegExp Syntax error: ";
        err += ex.getMessage();
        err += " ; error occured with the following " + "regular expression: " + rexpr;

        throw new IllegalArgumentException(err);
      }
    } else
      _regexp = null;
  } // -- setExpression

  /**
   * Returns true if the given String is matched by the regular expression of this RegExpEvaluator
   *
   * @param value the String to check the production of
   * @return true if the given string matches the regular expression of this RegExpEvaluator
   * @see #setExpression
   **/
  public boolean matches(String value) {
    // object to match compiled regular expressions
    Perl5Matcher matcher = new Perl5Matcher();
    // class for accessing results of pattern match
    return matcher.contains(value, _regexp);
  } // -- matches

} // -- JakartaOroEvaluator


