/*
 * $Source: /usr/cvsroot/melati/maven-dsd-plugin/src/main/java/org/melati/poem/prepro/ParsingDSDException.java,v $
 * $Revision: 1.14 $
 *
 * Copyright (C) 2000 William Chesters
 *
 * Part of Melati (http://melati.org), a framework for the rapid
 * development of clean, maintainable web applications.
 *
 * Melati is free software; Permission is granted to copy, distribute
 * and/or modify this software under the terms either:
 *
 * a) 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,
 *
 *    or
 *
 * b) any version of the Melati Software License, as published
 *    at http://melati.org
 *
 * You should have received a copy of the GNU General Public License and
 * the Melati Software License along with this program;
 * if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA to obtain the
 * GNU General Public License and visit http://melati.org to obtain the
 * Melati Software License.
 *
 * Feel free to contact the Developers of Melati (http://melati.org),
 * if you would like to work out a different arrangement than the options
 * outlined here.  It is our intention to allow Melati to be used by as
 * wide an audience as possible.
 *
 * 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.
 *
 * Contact details for copyright holder:
 *
 *     William Chesters <williamc At paneris.org>
 *     http://paneris.org/~williamc
 *     Obrechtstraat 114, 2517VX Den Haag, The Netherlands
 */

package org.melati.poem.prepro;

import java.io.StreamTokenizer;


/**
 * Thrown when an unexpected token is encountered during parsing.
 * Accommodates following  types of error. 
 * Syntactic assertion failures where the tokens found do not match 
 * those expected.
 * Vocabulary failures where values are outside the token set.
 * Model violations where legal expressions cannot actually be 
 * implemented, such as String troid columns.
 * Limitations on tables which must be either abstract or populated 
 * and must not hide a table in this or an imported DSD.     
 */
class ParsingDSDException extends RuntimeException {

  String expected, got;
  int lineNumber;
  String message;
  FieldDef field = null;

  /**
   * Constructor.
   */
  ParsingDSDException() {
    super();
  }

  ParsingDSDException(String expected, String got) {
    this.expected = expected;
    this.got = "\"" + got + "\"";
  }

  ParsingDSDException(String expected, StreamTokenizer got) {
    this.expected = expected;
    this.got = "\"" + got.toString() + "\"";
    this.lineNumber = got.lineno();
  }

  ParsingDSDException(String expected, 
                      String got, StreamTokenizer context) {
    this.expected = expected;
    this.got = "\"" + got + "\" near " + context.toString();
    this.lineNumber = context.lineno();
  }

  ParsingDSDException(int lineNo, String error) {
    this.message = error;
    this.lineNumber = lineNo;
  }

  /** @return the message */
  public String getMessage() {
    String returnString = "";
    if (lineNumber != 0)
      returnString = "Definition ending on line " + lineNumber + ": ";
    if (expected != null)
      returnString = returnString + "Expected \"" + expected + 
         "\" but got " + got + "\n";
    if (message != null)
      returnString = returnString + message;
    return returnString;
  }
}
