ScriptHandler.java

/*
 * This file is part of "JTA - Telnet/SSH for the JAVA(tm) platform".
 *
 * (c) Matthias L. Jugel, Marcus Meißner 1996-2005. All Rights Reserved.
 *
 * Please visit http://javatelnet.org/ for updates and contact.
 *
 * --LICENSE NOTICE--
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 * --LICENSE NOTICE--
 *
 */

package de.mud.telnet;

import java.util.Vector;

/**
 * A script handler, that tries to match strings and returns true when
 * it found the string it searched for.
 * <P>
 * <B>Maintainer:</B> Matthias L. Jugel
 *
 * @version $Id: ScriptHandler.java 499 2005-09-29 08:24:54Z leo $
 * @author Matthias L. Jugel, Marcus Mei�ner
 */
public class ScriptHandler {

  /** debugging level */
  private final static int debug = 0;

  private int matchPos;		// current position in the match
  private byte[] match;		// the current bytes to look for
  private boolean done = true;	// nothing to look for!

  /**
   * Setup the parser using the passed string. 
   * @param match the string to look for
   */
  public void setup(String match) {
    if(match == null) return;
    this.match = match.getBytes();
    matchPos = 0;
    done = false;
  }

  /**
   * Try to match the byte array s against the match string.
   * @param s the array of bytes to match against
   * @param length the amount of bytes in the array
   * @return true if the string was found, else false
   */
  public boolean match(byte[] s, int length) {
    if(done) return true;
    for(int i = 0; !done && i < length; i++) {
      if(s[i] == match[matchPos]) {
        // the whole thing matched so, return the match answer 
        // and reset to use the next match
        if(++matchPos >= match.length) {
          done = true;
          return true;
        }
      } else
        matchPos = 0; // get back to the beginning
    }
    return false;
  }
}