lemon/error.h
author Peter Kovacs <kpeter@inf.elte.hu>
Thu, 12 Nov 2009 23:26:13 +0100
changeset 806 fa6f37d7a25b
parent 291 d901321d6555
permissions -rw-r--r--
Entirely rework CapacityScaling (#180)

- Use the new interface similarly to NetworkSimplex.
- Rework the implementation using an efficient internal structure
for handling the residual network. This improvement made the
code much faster (up to 2-5 times faster on large graphs).
- Handle GEQ supply type (LEQ is not supported).
- Handle negative costs for arcs of finite capacity.
(Note that this algorithm cannot handle arcs of negative cost
and infinite upper bound, thus it returns UNBOUNDED if such
an arc exists.)
- Extend the documentation.
     1 /* -*- mode: C++; indent-tabs-mode: nil; -*-
     2  *
     3  * This file is a part of LEMON, a generic C++ optimization library.
     4  *
     5  * Copyright (C) 2003-2009
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     8  *
     9  * Permission to use, modify and distribute this software is granted
    10  * provided that this copyright notice appears in all copies. For
    11  * precise terms see the accompanying LICENSE file.
    12  *
    13  * This software is provided "AS IS" with no warranty of any kind,
    14  * express or implied, and with no claim as to its suitability for any
    15  * purpose.
    16  *
    17  */
    18 
    19 #ifndef LEMON_ERROR_H
    20 #define LEMON_ERROR_H
    21 
    22 /// \ingroup exceptions
    23 /// \file
    24 /// \brief Basic exception classes and error handling.
    25 
    26 #include <exception>
    27 #include <string>
    28 #include <sstream>
    29 #include <iostream>
    30 #include <cstdlib>
    31 #include <memory>
    32 
    33 namespace lemon {
    34 
    35   /// \addtogroup exceptions
    36   /// @{
    37 
    38   /// \brief Generic exception class.
    39   ///
    40   /// Base class for exceptions used in LEMON.
    41   ///
    42   class Exception : public std::exception {
    43   public:
    44     ///Constructor
    45     Exception() throw() {}
    46     ///Virtual destructor
    47     virtual ~Exception() throw() {}
    48     ///A short description of the exception
    49     virtual const char* what() const throw() {
    50       return "lemon::Exception";
    51     }
    52   };
    53 
    54   /// \brief Input-Output error
    55   ///
    56   /// This exception is thrown when a file operation cannot be
    57   /// succeeded.
    58   class IoError : public Exception {
    59   protected:
    60     std::string _message;
    61     std::string _file;
    62 
    63     mutable std::string _what;
    64   public:
    65 
    66     /// Copy constructor
    67     IoError(const IoError &error) throw() : Exception() {
    68       message(error._message);
    69       file(error._file);
    70     }
    71 
    72     /// Constructor
    73     explicit IoError(const char *message) throw() {
    74       IoError::message(message);
    75     }
    76 
    77     /// Constructor
    78     explicit IoError(const std::string &message) throw() {
    79       IoError::message(message);
    80     }
    81 
    82     /// Constructor
    83     explicit IoError(const char *message,
    84                      const std::string &file) throw() {
    85       IoError::message(message);
    86       IoError::file(file);
    87     }
    88 
    89     /// Constructor
    90     explicit IoError(const std::string &message,
    91                      const std::string &file) throw() {
    92       IoError::message(message);
    93       IoError::file(file);
    94     }
    95 
    96     /// Virtual destructor
    97     virtual ~IoError() throw() {}
    98 
    99     /// Set the error message
   100     void message(const char *message) throw() {
   101       try {
   102         _message = message;
   103       } catch (...) {}
   104     }
   105 
   106     /// Set the error message
   107     void message(const std::string& message) throw() {
   108       try {
   109         _message = message;
   110       } catch (...) {}
   111     }
   112 
   113     /// Set the file name
   114     void file(const std::string &file) throw() {
   115       try {
   116         _file = file;
   117       } catch (...) {}
   118     }
   119 
   120     /// Returns the error message
   121     const std::string& message() const throw() {
   122       return _message;
   123     }
   124 
   125     /// \brief Returns the filename
   126     ///
   127     /// Returns the filename or an empty string if it was not specified.
   128     const std::string& file() const throw() {
   129       return _file;
   130     }
   131 
   132     /// \brief Returns a short error message
   133     ///
   134     /// Returns a short error message which contains the message and the
   135     /// file name.
   136     virtual const char* what() const throw() {
   137       try {
   138         _what.clear();
   139         std::ostringstream oss;
   140         oss << "lemon:IoError" << ": ";
   141         oss << _message;
   142         if (!_file.empty()) {
   143           oss << " ('" << _file << "')";
   144         }
   145         _what = oss.str();
   146       }
   147       catch (...) {}
   148       if (!_what.empty()) return _what.c_str();
   149       else return "lemon:IoError";
   150     }
   151 
   152   };
   153 
   154   /// \brief Format error
   155   ///
   156   /// This exception is thrown when an input file has wrong
   157   /// format or a data representation is not legal.
   158   class FormatError : public Exception {
   159   protected:
   160     std::string _message;
   161     std::string _file;
   162     int _line;
   163 
   164     mutable std::string _what;
   165   public:
   166 
   167     /// Copy constructor
   168     FormatError(const FormatError &error) throw() : Exception() {
   169       message(error._message);
   170       file(error._file);
   171       line(error._line);
   172     }
   173 
   174     /// Constructor
   175     explicit FormatError(const char *message) throw() {
   176       FormatError::message(message);
   177       _line = 0;
   178     }
   179 
   180     /// Constructor
   181     explicit FormatError(const std::string &message) throw() {
   182       FormatError::message(message);
   183       _line = 0;
   184     }
   185 
   186     /// Constructor
   187     explicit FormatError(const char *message,
   188                          const std::string &file, int line = 0) throw() {
   189       FormatError::message(message);
   190       FormatError::file(file);
   191       FormatError::line(line);
   192     }
   193 
   194     /// Constructor
   195     explicit FormatError(const std::string &message,
   196                          const std::string &file, int line = 0) throw() {
   197       FormatError::message(message);
   198       FormatError::file(file);
   199       FormatError::line(line);
   200     }
   201 
   202     /// Virtual destructor
   203     virtual ~FormatError() throw() {}
   204 
   205     /// Set the line number
   206     void line(int line) throw() { _line = line; }
   207 
   208     /// Set the error message
   209     void message(const char *message) throw() {
   210       try {
   211         _message = message;
   212       } catch (...) {}
   213     }
   214 
   215     /// Set the error message
   216     void message(const std::string& message) throw() {
   217       try {
   218         _message = message;
   219       } catch (...) {}
   220     }
   221 
   222     /// Set the file name
   223     void file(const std::string &file) throw() {
   224       try {
   225         _file = file;
   226       } catch (...) {}
   227     }
   228 
   229     /// \brief Returns the line number
   230     ///
   231     /// Returns the line number or zero if it was not specified.
   232     int line() const throw() { return _line; }
   233 
   234     /// Returns the error message
   235     const std::string& message() const throw() {
   236       return _message;
   237     }
   238 
   239     /// \brief Returns the filename
   240     ///
   241     /// Returns the filename or an empty string if it was not specified.
   242     const std::string& file() const throw() {
   243       return _file;
   244     }
   245 
   246     /// \brief Returns a short error message
   247     ///
   248     /// Returns a short error message which contains the message, the
   249     /// file name and the line number.
   250     virtual const char* what() const throw() {
   251       try {
   252         _what.clear();
   253         std::ostringstream oss;
   254         oss << "lemon:FormatError" << ": ";
   255         oss << _message;
   256         if (!_file.empty() || _line != 0) {
   257           oss << " (";
   258           if (!_file.empty()) oss << "in file '" << _file << "'";
   259           if (!_file.empty() && _line != 0) oss << " ";
   260           if (_line != 0) oss << "at line " << _line;
   261           oss << ")";
   262         }
   263         _what = oss.str();
   264       }
   265       catch (...) {}
   266       if (!_what.empty()) return _what.c_str();
   267       else return "lemon:FormatError";
   268     }
   269 
   270   };
   271 
   272   /// @}
   273 
   274 }
   275 
   276 #endif // LEMON_ERROR_H