Exception.h

00001 // -*- mode:c++; tab-width:2; indent-tabs-mode:nil; c-basic-offset:2 -*-
00002 #ifndef __EXCEPTION_H__
00003 #define __EXCEPTION_H__
00004 
00005 /*
00006  *  Exception.h
00007  *  ZXing
00008  *
00009  *  Copyright 2010 ZXing authors All rights reserved.
00010  *
00011  * Licensed under the Apache License, Version 2.0 (the "License");
00012  * you may not use this file except in compliance with the License.
00013  * You may obtain a copy of the License at
00014  *
00015  *      http://www.apache.org/licenses/LICENSE-2.0
00016  *
00017  * Unless required by applicable law or agreed to in writing, software
00018  * distributed under the License is distributed on an "AS IS" BASIS,
00019  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00020  * See the License for the specific language governing permissions and
00021  * limitations under the License.
00022  */
00023 
00024 #include <string>
00025 #include <exception>
00026 
00027 namespace zxing {
00028 
00029 class Exception : public std::exception {
00030 private:
00031   char const* const message;
00032 
00033 public:
00034   Exception() throw() : message(0) {}
00035   Exception(const char* msg) throw() : message(copy(msg)) {}
00036   Exception(Exception const& that) throw() : std::exception(that), message(copy(that.message)) {}
00037   ~Exception() throw() {
00038     if(message) {
00039       deleteMessage();
00040     }
00041   }
00042   char const* what() const throw() {return message ? message : "";}
00043 
00044 private:
00045   static char const* copy(char const*);
00046   void deleteMessage();
00047 };
00048 
00049 }
00050 
00051 #endif // __EXCEPTION_H__