I haven't used try/catch blocks very often so I am very rusty on how to do these types of things. Anyway I have an exception class set up and a class that has operations that throw the exceptions. This is just meant as an exercise to remind me how exceptions are used. Anyway here is my code.
Exception class
#include <stdexcept>
#include <string>
using namespace std;
class TimeException: public logic_error
{
public:
TimeException(const string & message = ""): logic_error(message.c_str())
{}
};
Header file for time class
#ifndef TIME_H
#define TIME_H
#include "TimeException.h"
#include <iostream>
using namespace std;
class Time
{
public:
Time();
// Default constructor sets time to 0 hour and 0 minute
Time(int h, int m);
// Constructor that sets hour = h, and minute = m
int getHour() const;
// Returns hour
void setHour(int h) throw(TimeException);
// sets the hour = h
// Precondition: h >= 0 or h <= 24
// Postcondition: if h not within range program throws
// exception
int getMinute() const;
// Returns minute
void setMinute(int m) throw(TimeException);
// sets the minute = m
// Precondition: m >= or m < 60
// Postcondition: If m not within range program throws
// exception
void increaseMinutes(int m) throw(TimeException);
// Increases the minutes by m minutes
// Precondition: m > 0
// Postcondition: The minutes are increased by m minutes, minutes are measured
// by increments of 60, therefore if m exceeds 60 then hours is incremented as
// well as minutes appropriately according to 60 minutes = 1 hour
void display24HourNotation();
// Displays the 24 hour notation of time
void display12HourNotation();
// Displays the 12 hour notation of time
private:
int hour;
int minute;
};
#endif
Time.cpp file
#include "Time.h"
Time::Time(): hour(0), minute(0)
{}
Time::Time(int h, int m): hour(h), minute(m)
{}
int Time::getHour() const
{
return hour;
}
void Time::setHour(int h) throw(TimeException)
{
if(h < 0 || h > 24)
{
throw TimeException("Time Exception: Bad hour on setHour");
}
hour = h;
}
int Time::getMinute() const
{
return minute;
}
void Time::setMinute(int m) throw(TimeException)
{
if(m < 0 || m >= 60)
{
throw TimeException("Time Exception: Bad minute on setMinute");
}
minute = m;
}
void Time::increaseMinutes(int m) throw(TimeException)
{
if(m <= 0)
{
throw TimeException("Time Exception: can not increase <= 0 minutes");
}
// add m to minute value
minute += m;
// need to get the hour correct along side minute
if(minute >= 60)
{
// minute is actually hour now therefore must be
// changed to have the correct value
hour += minute / 60; // correct hour value
minute = minute % 60; // correct minute value
}
// need to double check to make sure hour isn't exceeding
// the 24 hour limit
hour = hour % 24; // correct hour value
}
void Time::display24HourNotation()
{
// show time in 24 hour notation
// hour/minutes stored in 24 hour notation
// therefore just print time
if(minute < 10)
cout << "Time in 24 hour notation is: " << hour << ":0" << minute << endl;
else
cout << "Time in 24 hour notation is: " << hour << ":" << minute << endl;
}
void Time::display12HourNotation()
{
// show time in 12 hour notation
// need to specify between am and pm
int hour12;
if(hour >= 12 && hour < 24)
{
// your in the PM
if(hour == 12)
hour12 = hour;
else
hour12 = hour - 12;
if(minute < 10)
cout << "Time in 12 hour notation is: " << hour12 << ":0" << minute << " PM\n";
else
cout << "Time in 12 hour notation is: " << hour12 << ":" << minute << " PM\n";
}
else
{
int hour12;
// your in the AM
if(hour == 24)
hour12 = 12;
else
hour12 = hour;
if(minute < 10)
cout << "Time in 12 hour notation is: " << hour12 << ":0" << minute << " AM\n";
else
cout << "Time in 12 hour notation is: " << hour12 << ":" << minute << " AM\n";
}
}
The driver program
#include "Time.h"
int main()
{
Time t, t2(8,35);
/*cout << t.getHour() << endl;
cout << t.getMinute() << endl;
cout << t2.getHour() << endl;
cout << t2.getMinute() << endl;*/
try
{
t.setHour(-1);
}
catch(TimeException e)
{
e.what();
}
/*cout << t.getHour() << endl;
t.setHour(32);
cout << t.getHour() << endl;
t.setMinute(30);
cout << t.getMinute() << endl;
t.setMinute(60);
cout << t.getMinute() << endl;*/
t2.display24HourNotation();
t2.display12HourNotation();
t2.increaseMinutes(30);
//cout << t2.getHour() << endl;
//cout << t2.getMinute() << endl;
t2.display24HourNotation();
t2.display12HourNotation();
return 0;
}
Basically when i execute the try catch block nothing happens with e.what(), which I thought was suppose to print my error message. Just so you know when I put a normal cout statement in the catch block it writes information there so clearly it's making it to the block it's intended to. Any help would be appreciated. Thanks.
