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COMP2301 – Assignment Four – File I/O in C++

This assignment is a pass/fail assignment. I achieved a pass.

The goal of this assignment is to gain experience using C++ for object-oriented programming.

In this assignment, you will become familiar with:

• C++ I/O methods: operator << and operator >>
• Use of classes in C++
• Some aspects of the standard template library (STL)

Specification

Develop a command-line program to read and manipulate a file of internet banking transactions. Each individual transaction starts on a new line and contains six comma separated transaction details.

1. Timestamp: 10-digit: [yymmddhhnnss],   [yy] = year, [mm] = month, [dd] = day, [hh] = hour (from [00] to [23]), [nn] = minutes,  [ss] = seconds.
2. Customer’s last name:
3. Customer reference number: 10-digit number.
4. Account type : “Check” for (Checking account), “Sav” for (Savings account) or “Cred” for (Credit card account).
5. Transaction type : “Dep” for (Deposit) or “With” for (Withdrawal).
6. Transaction amount: [dollars.cc], where [dolars] = integer dollars and  [cc] = integer cents.

Example input file containing four transaction: ( Timestamp, Customer’s last name, customer reference number, Account type , Transaction type , Transaction amount )
0405031220, Howard, 6434199921, Check, With, 230.20 0405040936, Schwarzenegger, 4873123321, Sav, Dep, 5000000.00 0405031322, Jackson, 3856927195, Cred, With, 2500.00 0405051816, Schwarzenegger, 4873123321, Sav, With, 2000000.00  

Functions required for the command line interface

• The program sorts the transactions when run from the command line in three ways:
      transactionlist [ [/t] | [/n] | [/c] ] INPUTFILE [OUTPUTFILE]
                               /t [DEFAULT]    : sort transactions in Numeric order by Time Stamp
                               /n                        : sort transactions in Alphabetic order by Last Name
                               /c                        : sort transactions in Numeric order by Time Stamp of combined deposit balance
• An error is generated if more than one command line switch is entered.
• If no command line switch is entered the default operation executes and the program writes the sorted transactions to standard output (cout).
• If an [OUTPUTFILE] is specified the program writes the sorted transactions to the named file.  Existing file content should be overwritten.
• If [/c] the combined balance switch is entered all transactions with identical customer reference numbers AND identical account types must be combined into one transaction.
  • Time stamp of the combined transaction = Time stamp of the last transaction that corresponds to the appropriate customer reference number and account type
  • Transaction type of the combined transaction is “CombDep” (CombinedDeposit)
  • Transaction amount is the [sum of all appropriate deposits] - [sum of all appropriate withdrawals]
• You are to implement the operator <<, operator >>, operator /=, operator + and comparison operators.
  • operator <<, operator >> are to be used to read the file and write to cout.
  • operator /=  is used to test if two transactions have identical customer reference numbers AND account types.
  • operator + combines two transactions.

General

• You will need to write a class called “transaction” in this assignment.
• You must NOTuse stdio.h (i.e. scanf, printf, etc.).
• You may use strcpy, sscanf, and other string manipulation routines included in string.h.
• You MUST use the Standard Template Library’s list (or vector).
• Running your program with no command line parameters must generate a usage statement.
• All transactions with identical customer reference numbers have identical last names
• Transaction amount for a combined balance may be negative.
• Reasonable error checking is required, the program must handle the following events gracefully
  • the specified input file does not exist.
  • an incorrect number of command line parameters are given.
  • the file contains invalid records or an invalid record structure.
• Transaction.h header file may be obtained by downloading the Zip file for assignment 4.

Compiled (WIN32) binary (188 KB)
transaction.h
transaction.cpp

transaction.h
/* * * Subsystem: TRANSACTION * * File Name: transaction.h * * Author: Stefan Lehmann * Modified: Ned Martin 40529927, 18-MAY-2004 * * Date Created: 07/03/2004 * * Description: Header file for Transaction class. * */ #ifndef __TRANSACTION_H__ #define __TRANSACTION_H__ class Transaction; istream& operator >> (istream& ioStream, Transaction& iTransaction); ostream& operator << (ostream& ioStream, const Transaction& iTransaction); class Transaction { public: /* * Name: Transaction() * * Purpose: Default Constructor * * Method: Initialise data members */ Transaction(); /* * Name: Transaction() * * Purpose: Constructor with arguments * * Method: Initialise data members with given info */ Transaction(long iTimeStamp, char *iCustomerName, long iCustomerRefNum, char *iAccountType, char *iTransactionType, float iAmount); /* * Name: ~Transaction() * * Purpose: Destructor * * Method: Deallocate memory */ ~Transaction(); // operators /* * Name: operator == * * Purpose: Equality operator * * Method: Checks if Transaction is the same. */ bool operator== (const Transaction& iRightParameter); /* * Name: operator != * * Purpose: Inequality operator * * Method: Checks if Transaction is NOT the same. */ bool operator!= (const Transaction& iRightParameter); /* * Name: operator /= * * Purpose: Combined transaction test operator * * Method: Checks if Transaction has identical customer ref# * and account type */ bool operator/= (const Transaction& iRightParameter); /* * Name: operator < * * Purpose: Less than * * Method: Checks if Transaction is less than. */ bool operator< (const Transaction& iRightParameter); /* * Name: operator > * * Purpose: Greater than * * Method: Checks if Transaction is greater than. */ bool operator> (const Transaction& iRightParameter); /* * Name: operator = * * Purpose: Copy * * Method: Ensure a deep copy. */ Transaction& operator= (const Transaction& iRightParameter); /* * Name: operator + * * Purpose: Combine * * Method: Combine Transaction with other Transaction */ Transaction& operator+ (const Transaction& iRightParameter); static void Transaction::setSortBy (int iFieldToSortBy) { mSortBy = iFieldToSortBy; } // Friend functions /* * Name: operator >> * * Purpose: Input operation * * Method: Assume comma separated values, Time Stamp first. */ friend istream& operator >> (istream& ioStream, Transaction& iTransaction); /* * Name: operator << * * Purpose: Output operation * * Method: Output comma separated values, Time Stamp first. */ friend ostream& operator << (ostream& ioStream, const Transaction& iTransaction); enum { kSORT_BY_TIMESTAMP }; private: static int mSortBy; // Insert Transaction data entries here // Transaction data entries long TimeStamp; char CustomerName[300]; // value exceeds long, changed to char array char CustomerRefNum[300]; char AccountType[300]; char TransactionType[300]; float Amount; }; #endif //__TRANSACTION_H__

transaction.cpp
/* * Author: Ned Martin #40529927 * * Creation Date: 18-MAY-2004 * * Version: FINAL 18-MAY-2004 * * Copyright: Copyright (c) 2004 Ned Martin, Student s40529927, * for COMP2301, University of Queensland * * Description: Assignment 4 for COMP2301 * Reads an input file, parses file for tokens, reads each * line into a Transaction, stores Transactions in a list, * and depending on commandline input, sorts list in a * variety of ways, or combines specific Transactions, * then either prints them out to cout or to a specified * file. May also cause hair loss. * * Restrictions: Basic error checking is performed on the input file, * but generally it is assumed to be in a valid format as * per the assignment specification. * * Usage: [ [/t] | [/n] | [/c] ] INPUTFILE [OUTPUTFILE] * /t [DEFAULT] : sort transactions in Numeric * order by Time Stamp * /n : sort transactions in * Alphabetic order by Last Name * /c : sort transactions in Numeric * order by Time Stamp of combined * * Tab Stops: Eight spaces */ #include <stdlib.h> // EXIT_SUCCESS, EXIT_FAILURE #include <iostream> // cout, cerr, shift operators #include <fstream> // file streams #include <list> // list, iterator #include <string> // strlen, string functions #include <iomanip> // setw, setfill, setprecision using namespace std; #include "transaction.h" bool combine; // flag specifying when we are combining transactions // set mSortBy to 0 so we sort by Numeric Order of Timestampe by default int Transaction::mSortBy = 0; /* * Function: stripSpace * * Purpose: Strips leading spaces from a string. * * Method: Accepts pointer to char string and returns pointer to first * non-space character in string pointed to. * * Returns: char pointer to stripped string. */ char* stripSpace ( char* temp // pointer to string ) { int ii; // counter char *p; // holds temporary string p = temp; for (ii = 0; ii < strlen (temp); ii++) { // first non-space char is found so exit loop if (!isspace (temp[ii])) { break; } } p += ii; strcpy (temp, p); return temp; } // end stripSpace /* * Name: Transaction() * * Purpose: Default Constructor * * Method: Initialise data members * * Note: There is nothing to do here. */ Transaction::Transaction() { // There is nothing to initialise } /* * Name: ~Transaction() * * Purpose: Destructor * * Method: Deallocate memory * * Note: There is nothing to do here. */ Transaction::~Transaction() { // There is nothing to destroy. } // begin redefining operators /* * Name: operator /= * * Purpose: Combined transaction test operator * * Method: Checks if Transaction has identical customer ref# * and account type */ bool Transaction::operator/= ( const Transaction& iRightParameter // right hand operand ) { // return true when customer ref num and account type of both // transactions are equal return (!(strcmp (CustomerRefNum, iRightParameter.CustomerRefNum)) && !(strcmp (AccountType, iRightParameter.AccountType))); } // end operator/= /* * Name: operator < * * Purpose: Less than * * Method: Checks if Transaction is less than. */ bool Transaction::operator< ( const Transaction& iRightParameter // right hand operand ) { // sorting by customer name if( mSortBy ) { return (strcmp (CustomerName, iRightParameter.CustomerName) == -1); } // sorting by timestamp else { return (TimeStamp < iRightParameter.TimeStamp); } } // end operator< /* * Name: operator > * * Purpose: Greater than * * Method: Checks if Transaction is greater than. * * Note: This is not currently used. */ bool Transaction::operator> ( const Transaction& iRightParameter // right hand operand ) { // sorting by customer name if( mSortBy ) { return (strcmp (CustomerName, iRightParameter.CustomerName) == 1); } // sorting by timestamp else { return (TimeStamp > iRightParameter.TimeStamp); } } // end operator> /* * Name: operator + * * Purpose: Combine * * Method: Combine Transaction with other Transaction */ Transaction& Transaction::operator+ ( const Transaction& iRightParameter // right hand operand ) { float amount = 0; // holds temporary amount // set timestamp to new timestamp only if new timestamp is newer if( iRightParameter.TimeStamp > TimeStamp ) { TimeStamp = iRightParameter.TimeStamp; } // set type of transaction to "CombDep" strcpy (TransactionType, "CombDep"); // sum amounts // negative amount if transaction type is withdrawal if( strcmp (iRightParameter.TransactionType, "With") == 0 ) { amount -= iRightParameter.Amount; } // positive amount if transaction is deposit else { amount += iRightParameter.Amount; } // negative amount if transaction type is withdrawal if( strcmp (TransactionType, "With") == 0 ) { amount -= Amount; } // positive amount if transaction is deposit else { amount += Amount; } Amount = amount; return *this; } // end operator+ /* * Name: operator >> * * Purpose: Input operation * * Method: Assume comma separated values, Time Stamp first. */ istream& operator >> ( istream& ioStream, // input ioStream Transaction& iTransaction // output Transaction ) { char tempString[300]; // temporary array char delim = ','; // deliminator // tokenise on deliminators // long ioStream.getline (tempString, 256, delim); stripSpace(tempString); iTransaction.TimeStamp = atol (tempString); // invalid timestamp if( !(iTransaction.TimeStamp > 0) ) { cerr << "Invalid Input Detected" << endl; exit (EXIT_FAILURE); } //char[] ioStream.getline (tempString, 256, delim); stripSpace(tempString); strcpy (iTransaction.CustomerName, tempString); // long ioStream.getline (tempString, 256, delim); stripSpace(tempString); strcpy (iTransaction.CustomerRefNum, tempString); // char[] ioStream.getline (tempString, 256, delim); stripSpace(tempString); strcpy (iTransaction.AccountType, tempString); // char[] ioStream.getline (tempString, 256, delim); stripSpace(tempString); strcpy (iTransaction.TransactionType, tempString); // float // read to end of line ioStream.getline (tempString, 256); stripSpace(tempString); iTransaction.Amount = atof (tempString); return ioStream; } // end operator >> /* * Name: operator << * * Purpose: Output operation * * Method: Output comma separated values, Time Stamp first. */ ostream& operator << ( ostream& ioStream, // output ioStream const Transaction& iTransaction // input Transaction ) { // long // set width to 10 and fill with 0's ioStream << setw (10) << setfill ('0') << iTransaction.TimeStamp << ", "; // char* ioStream << iTransaction.CustomerName << ", "; // long ioStream << iTransaction.CustomerRefNum << ", "; // char* ioStream << iTransaction.AccountType << ", "; // char* ioStream << iTransaction.TransactionType << ", "; // float // set precision to 2 and fixed notation ioStream << setprecision (2) << fixed << iTransaction.Amount << endl; return ioStream; } // end operator << // end operators /* * Function: checkSwitch * * Purpose: Checks commandline input for valid switches. * * Method: Accepts array of characters and tests to see if it contains * valid switches. Sets bool combine to true if switch was 'c', * sets mSortBy to 1 if switch was 'n'. * * Returns: true if valid switch was encountered. false otherwise. */ bool checkSwitch ( char args[] // array containing possible switch ) { // check if it is a valid argument beginning with '/' or '-' switch( args[0] ) { case '/': case '-': break; default : return false; } // check that the second char is a valid char, 't', 'n' or 'c' switch( args[1] ) { // sort transactions in Numeric order by Time Stamp case 't': //Transaction::setSortBy ( 0 ) is already set // dont need to do anything here break; // sort transactions in Alphabetic order by Last Name case 'n': Transaction::setSortBy ( 1 ); break; // sort transactions in Numeric order by Time Stamp of combined // deposit balance case 'c': combine = true; break; // is not valid switch default : return false; break; } // is a valid switch return true; } // end checkSwitch /* * Function: main * * Purpose: Does heaps of things, causes headaches and hair loss. * * Method: Parses commandline input, creates Transactions from an input * file, adds them to list, sorts this list, possibly combines * transactions, and prints them out to cout or a file. * * Returns: EXIT_SUCCESS on success */ int main ( int argc, char *argv[] ) { ofstream outputFile; // Output file ifstream inputFile; // Input file bool printToFile = false; // file printing flag list<Transaction> transactions; // list to hold Transactions list<Transaction>::iterator transactionsIterator; // iterator over list // create a new Transaction Transaction *transaction = new Transaction(); // parse commandline arguments switch( argc - 1 ) { // switch, inputfile, outputfile case 3: // check switch checkSwitch(argv[1]); // open files inputFile.open (argv[2]); outputFile.open (argv[3]); break; // input file, output file OR switch, input file case 2: // if 1 is switch then 2 is input file if( checkSwitch(argv[1]) ) { // 2 is input file inputFile.open (argv[2]); } // else 1 is input and 2 is output else { inputFile.open (argv[1]); outputFile.open (argv[2]); } break; // input file case 1: // open file inputFile.open (argv[1]); break; // is an error so print error msg and exit default : cerr << "Usage: " << argv[0] << " "; cerr << "[ [/t] | [/n] | [/c] ] INPUTFILE [OUTPUTFILE]\n"; cerr << "/t [DEFAULT]\t: sort transactions in Numeric order by " << "Time Stamp\n"; cerr << "/n\t\t: sort transactions in Alphabetic order by Last " << "Name\n"; cerr << "/c\t\t: sort transactions in Numeric order by Time " << "Stamp of combined deposit balance" << endl; exit (EXIT_FAILURE); break; } // input file is bad so print error and exit if( !inputFile.good() ) { cerr << "Invalid Input File" << endl; exit (EXIT_FAILURE); } // output file is open so we are printing to output file if( outputFile.is_open() ) { printToFile = true; } // for each line in the input file while( !inputFile.eof() ) { // parse input stream into transaction inputFile >> *transaction; // add Transaction to list transactions.push_back(*transaction); } // sort list of transactions depending on mSortBy flag transactions.sort(); /* Combine transactions assume transactions are sorted by cust ref for all ii for all jj where jj = ii + 1 if transaction[ii] /= transaction[jj] then combine transactions by transaction[ii] = transaction[ii] + transaction[jj] remove transaction[jj] from list */ if( combine ) { // create iterators over the list of Transactions list<Transaction>::iterator ii; list<Transaction>::iterator jj; for (ii = transactions.begin(); ii != transactions.end(); ii++) { for (jj = ii; jj != transactions.end(); jj++) { if( (ii != jj) && (*ii /= *jj) ) { *ii + *jj; if (jj != transactions.end()) { transactions.erase(jj++); } } } } } // print list of transactions for (transactionsIterator = transactions.begin(); transactionsIterator != transactions.end(); transactionsIterator++) { // print to file if( printToFile ) { outputFile << *transactionsIterator; } // print to cout else { cout << *transactionsIterator; } } // close files outputFile.close(); inputFile.close(); // destroy transaction delete transaction; return EXIT_SUCCESS; } // end main
Code © Copyright 2004 Ned Martin

19-May-2004