/interpreter/tags/at2-build190607/src/edu/vub/util/PatternSyntaxException.java

  1/* PatternSyntaxException - Indicates illegal pattern for regular expression.
  2Copyright (C) 2002 Free Software Foundation, Inc.
  3
  4This file is part of GNU Classpath.
  5
  6GNU Classpath is free software; you can redistribute it and/or modify
  7it under the terms of the GNU General Public License as published by
  8the Free Software Foundation; either version 2, or (at your option)
  9any later version.
 10
 11GNU Classpath is distributed in the hope that it will be useful, but
 12WITHOUT ANY WARRANTY; without even the implied warranty of
 13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 14General Public License for more details.
 15
 16You should have received a copy of the GNU General Public License
 17along with GNU Classpath; see the file COPYING.  If not, write to the
 18Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 1902111-1307 USA.
 20
 21Linking this library statically or dynamically with other modules is
 22making a combined work based on this library.  Thus, the terms and
 23conditions of the GNU General Public License cover the whole
 24combination.
 25
 26As a special exception, the copyright holders of this library give you
 27permission to link this library with independent modules to produce an
 28executable, regardless of the license terms of these independent
 29modules, and to copy and distribute the resulting executable under
 30terms of your choice, provided that you also meet, for each linked
 31independent module, the terms and conditions of the license of that
 32module.  An independent module is a module which is not derived from
 33or based on this library.  If you modify this library, you may extend
 34this exception to your version of the library, but you are not
 35obligated to do so.  If you do not wish to do so, delete this
 36exception statement from your version. */
 37
 38package edu.vub.util;
 39
 40/**
 41 * Indicates illegal pattern for regular expression.
 42 * Includes state to inspect the pattern and what and where the expression
 43 * was not valid regular expression.
 44 */
 45public class PatternSyntaxException extends IllegalArgumentException
 46{
 47  private static final long serialVersionUID = -3864639126226059218L;
 48
 49  /**
 50   * Human readable escription of the syntax error.
 51   */
 52  private final String desc;
 53
 54  /**
 55   * The original pattern that contained the syntax error.
 56   */
 57  private final String pattern;
 58
 59  /**
 60   * Index of the first character in the String that was probably invalid,
 61   * or -1 when unknown.
 62   */
 63  private final int index;
 64
 65  /**
 66   * Creates a new PatternSyntaxException.
 67   *
 68   * @param description Human readable escription of the syntax error.
 69   * @param pattern The original pattern that contained the syntax error.
 70   * @param index Index of the first character in the String that was
 71   *        probably invalid, or -1 when unknown.
 72   */
 73  public PatternSyntaxException(String description,
 74      String pattern,
 75      int index)
 76  {
 77    super(description);
 78    this.desc = description;
 79    this.pattern = pattern;
 80    this.index = index;
 81  }
 82
 83  /**
 84   * Returns a human readable escription of the syntax error.
 85   */
 86  public String getDescription()
 87  {
 88    return desc;
 89  }
 90
 91  /**
 92   * Returns the original pattern that contained the syntax error.
 93   */
 94  public String getPattern()
 95  {
 96    return pattern;
 97  }
 98
 99  /**
100   * Returns the index of the first character in the String that was probably
101   * invalid, or -1 when unknown.
102   */
103  public int getIndex()
104  {
105    return index;
106  }
107
108  /**
109   * Returns a string containing a line with the description, a line with
110   * the original pattern and a line indicating with a ^ which character is
111   * probably the first invalid character in the pattern if the index is not
112   * negative.
113   */
114  public String getMessage()
115  {
116    String lineSep = System.getProperty("line.separator");
117    StringBuffer sb = new StringBuffer(desc);
118    sb.append(lineSep);
119    sb.append('\t');
120    sb.append(pattern);
121    if (index != -1)
122    {
123      sb.append(lineSep);
124      sb.append('\t');
125      for (int i=0; i<index; i++)
126        sb.append(' ');
127      sb.append('^');
128    }
129    return sb.toString();
130  }
131
132}