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Maven 3 Plugin for processing JavaCC grammar files.
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/* Copyright (c) 2006, Sun Microsystems, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of the Sun Microsystems, Inc. nor the names of its
 *       contributors may be used to endorse or promote products derived from
 *       this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, 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.
 */
package org.javacc.parser;

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

/**
 * Describes regular expressions.
 */

public abstract class RegularExpression extends Expansion
{

  /**
   * The label of the regular expression (if any). If no label is present, this
   * is set to "".
   */
  public String label = "";

  /**
   * The ordinal value assigned to the regular expression. It is used for
   * internal processing and passing information between the parser and the
   * lexical analyzer.
   */
  int ordinal;

  /**
   * The LHS to which the token value of the regular expression is assigned. In
   * case there is no LHS, then the list remains empty.
   */
  public List lhsTokens = new ArrayList ();

  /**
   * We now allow qualified access to token members. Store it here.
   */
  public Token rhsToken;

  /**
   * This flag is set if the regular expression has a label prefixed with the #
   * symbol - this indicates that the purpose of the regular expression is
   * solely for defining other regular expressions.
   */
  public boolean private_rexp = false;

  /**
   * If this is a top-level regular expression (nested directly within a
   * TokenProduction), then this field point to that TokenProduction object.
   */
  public TokenProduction tpContext = null;

  public abstract Nfa GenerateNfa (boolean ignoreCase);

  public boolean CanMatchAnyChar ()
  {
    return false;
  }

  /**
   * The following variable is used to maintain state information for the loop
   * determination algorithm: It is initialized to 0, and set to -1 if this node
   * has been visited in a pre-order walk, and then it is set to 1 if the
   * pre-order walk of the whole graph from this node has been traversed. i.e.,
   * -1 indicates partially processed, and 1 indicates fully processed.
   */
  int walkStatus = 0;

  @Override
  public StringBuffer dump (final int indent, final Set alreadyDumped)
  {
    final StringBuffer sb = super.dump (indent, alreadyDumped);
    alreadyDumped.add (this);
    sb.append (' ').append (label);
    return sb;
  }
}