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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 lookahead rule for a particular expansion or expansion sequence
 * (See Sequence.java). In case this describes the lookahead rule for a single
 * expansion unit, then a sequence is created with this node as the first
 * element, and the expansion unit as the second and last element.
 */

public class Lookahead extends Expansion
{

  /**
   * Contains the list of tokens that make up the semantic lookahead if any. If
   * this node represents a different kind of lookahead (other than semantic
   * lookahead), then this list contains nothing. If this list contains
   * something, then it is the boolean expression that forms the semantic
   * lookahead. In this case, the following fields "amount" and "la_expansion"
   * are ignored.
   */
  private final List action_tokens = new ArrayList ();

  /**
   * The lookahead amount. Its default value essentially gives us infinite
   * lookahead.
   */
  private int amount = Integer.MAX_VALUE;

  /**
   * The expansion used to determine whether or not to choose the corresponding
   * parse option. This expansion is parsed upto "amount" tokens of lookahead or
   * until a complete match for it is found. Usually, this is the same as the
   * expansion to be parsed.
   */
  private Expansion la_expansion;

  /**
   * Is set to true if this is an explicit lookahead specification.
   */
  private boolean isExplicit;

  @Override
  public StringBuffer dump (final int indent, final Set alreadyDumped)
  {
    final StringBuffer sb = super.dump (indent, alreadyDumped).append (isExplicit ? " explicit" : " implicit");
    if (alreadyDumped.contains (this))
      return sb;
    alreadyDumped.add (this);
    sb.append (eol).append (la_expansion.dump (indent + 1, alreadyDumped));
    return sb;
  }

  /**
   * @return the action_tokens
   */
  public List getActionTokens ()
  {
    return action_tokens;
  }

  /**
   * @param amount
   *        the amount to set
   */
  public void setAmount (final int amount)
  {
    this.amount = amount;
  }

  /**
   * @return the amount
   */
  public int getAmount ()
  {
    return amount;
  }

  /**
   * @param la_expansion
   *        the la_expansion to set
   */
  public void setLaExpansion (final Expansion la_expansion)
  {
    this.la_expansion = la_expansion;
  }

  /**
   * @return the la_expansion
   */
  public Expansion getLaExpansion ()
  {
    return la_expansion;
  }

  /**
   * @param isExplicit
   *        the isExplicit to set
   */
  public void setExplicit (final boolean isExplicit)
  {
    this.isExplicit = isExplicit;
  }

  /**
   * @return the isExplicit
   */
  public boolean isExplicit ()
  {
    return isExplicit;
  }
}