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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.Set;

/**
 * Describes expansions - entities that may occur on the right hand sides of
 * productions. This is the base class of a bunch of other more specific
 * classes.
 */

public class Expansion
{

  /**
   * The line and column number of the construct that corresponds most closely
   * to this node.
   */
  private int line;

  private int column;

  /**
   * A reimplementing of Object.hashCode() to be deterministic. This uses the
   * line and column fields to generate an arbitrary number - we assume that
   * this method is called only after line and column are set to their actual
   * values.
   */
  @Override
  public int hashCode ()
  {
    return getLine () + getColumn ();
  }

  /**
   * An internal name for this expansion. This is used to generate parser
   * routines.
   */
  String internal_name = "";

  /**
   * The parser routines are generated in three phases. The generation of the
   * second and third phase are on demand only, and the third phase can be
   * recursive. This variable is used to keep track of the expansions for which
   * phase 3 generations have been already added to a list so that the recursion
   * can be terminated.
   */
  boolean phase3done = false;

  /**
   * The parent of this expansion node. In case this is the top level expansion
   * of the production it is a reference to the production node otherwise it is
   * a reference to another Expansion node. In case this is the top level of a
   * lookahead expansion,then the parent is null.
   */
  public Object parent;

  /**
   * The ordinal of this node with respect to its parent.
   */
  int ordinal;

  /**
   * To avoid right-recursive loops when calculating follow sets, we use a
   * generation number which indicates if this expansion was visited by
   * LookaheadWalk.genFollowSet in the same generation. New generations are
   * obtained by incrementing the static counter below, and the current
   * generation is stored in the non-static variable below.
   */
  public static long nextGenerationIndex = 1;
  public long myGeneration = 0;

  /**
   * This flag is used for bookkeeping by the minimumSize method in class
   * ParseEngine.
   */
  public boolean inMinimumSize = false;

  public static void reInit ()
  {
    nextGenerationIndex = 1;
  }

  private String getSimpleName ()
  {
    final String name = getClass ().getName ();
    return name.substring (name.lastIndexOf (".") + 1); // strip the package
                                                        // name
  }

  @Override
  public String toString ()
  {
    return "[" + getLine () + "," + getColumn () + " " + System.identityHashCode (this) + " " + getSimpleName () + "]";
  }

  protected static final String eol = System.getProperty ("line.separator", "\n");

  protected StringBuffer dumpPrefix (final int indent)
  {
    final StringBuffer sb = new StringBuffer (128);
    for (int i = 0; i < indent; i++)
      sb.append ("  ");
    return sb;
  }

  public StringBuffer dump (final int indent, final Set alreadyDumped)
  {
    final StringBuffer value = dumpPrefix (indent).append (System.identityHashCode (this))
                                                  .append (" ")
                                                  .append (getSimpleName ());
    return value;
  }

  /**
   * @param column
   *        the column to set
   */
  void setColumn (final int column)
  {
    this.column = column;
  }

  /**
   * @return the column
   */
  int getColumn ()
  {
    return column;
  }

  /**
   * @param line
   *        the line to set
   */
  void setLine (final int line)
  {
    this.line = line;
  }

  /**
   * @return the line
   */
  int getLine ()
  {
    return line;
  }
}