CS 596 OODP
Introduction to OO

1. References
2. Introduction
   1. History and Languages
   2. Methodologies
   3. Meyer's Criteria for Evaluating for Modularity
   4. Principles for Software Development
3. Simple C++ IO
   1. IO Operators
   2. Some IO Goodies
   3. File IO
   4. How to find out more about Streams
4. What is Object-Oriented Programming
   1. Language Level Definition
   2. Conceptual Level Definition

Step-by-step methods

Graphical notation

Documentation techniques

Principles, guidelines, policies

Booch

Shlaer & Mellor

Rumbaugh et al.

Coad & Yourdon

European Space Agency, HOOD Working Group

Wirfs-Brock et al.

Jacobson

Behind schedule

Over budget

Foreign competition

Buggy software lacks features

Too expensive

Why can't you make this "little" change?

Multiple platforms

Unix

PowerPC

Dos

Macintosh

Client/Server Applications

GUIs

X Windows

Motif

Microsoft Windows

Understandablity

Composability

Decomposability

Composability

Understandability

#include <iostream.h>

void main()

{

cout << "Hello World\n";

}

Start with working program

Add small pieces of code and debug

#include <iostream.h>

void main() 
{
	int accessCode;
	float transactionAmount;
	char userName[50];
	
	cout << "Please enter:  
			your name, access code and amount\n";

	cin >> userName>> accessCode>> transactionAmount;
	
	cout 	<< "Your input: ";
	cout 	<< userName 
			<< accessCode  
			<< transactionAmount
			<< endl ;
}

Removes all white space

Accepts multiple input values in order - left to right

Returns false when reaches end-of-file condition

add "\n" and flush output buffer

cin

standard input

cout

standard output (buffered)

cerr

standard error

clog

standard error, but buffered

#include <iostream.h>

void main()
{
	int integerInput;
	for (int K = 0; K < 8;K++)
	{
		cin >> integerInput;
		cout << integerInput;
	};
}

	Input	Output

1 2 3 4.5 6 7 8 9		12344444

Removes a single character from the input stream and places it in ch

Stores characters in the array dest, until

it encounters the delimiter, delim

or it has read length -1 characters

or reaches end of file

dest is terminated with a null character

delim is not removed from the input stream

Places a single character into the output stream

#include <iostream.h>

void main()
{
	char userInput;

	while (cin.get(userInput))

		cout.put(userInput);
}

#include <iostream.h>

void main()
{
	int userInput;

	while ((userInput = cin.get()) != EOF)

		cout.put(userInput);
}

#include <iostream.h>

void main()
{
	char userInput;

	while ( cin >> userInput )

		cout << userInput;
}

#include <iostream.h>

void main()
{
	char buffer[100];

	cin >> buffer;	// Not safe, can overflow

	cin.get(buffer, 100, '\n');	// Safe


	char next;

	if ( (cin.get(next)  && next) != '\n') {

	// If reach here input line was longer than 
	// 99 characters 

	}
}

Reads either limit-1 characters, or to the delimiter, which ever comes first. Places characters read in buffer, Adds null character to buffer. Does not flush input to next line.

Reads the size number of bytes from the input, places them in buffer

Disregards up to limit characters in input stream, stops if encounters delimit character

#include <iostream.h>
void main() {
	char	buffer[10];
	char	overFlow[10];

	cin.getline(buffer, sizeof(buffer));

	cin.getline(overFlow, sizeof(buffer), 'x');

	cout	<< buffer<<'\t' 
			<< overFlow << endl;
}

#include <iostream.h>
#include <iomanip.h>

void main()
{
        int x;
        x = 8;
        cout << setw(12) << x << endl;
        cout << oct << x << '\t' 
				<< x 
				<< endl;	// 8 in octal is 10
        cout << hex << x << endl;

}

           8
10      10
8

cout << flush	// flush io buffer

cout << endl	// insert newline (\n) and then flush buffer

cout << ends	// insert a null(0) character

	// used for array output with strstreams

#include <iostream.h>
#include <iomanip.h>

void main() 
{
	char name[10];
	char address[10];
	
	cout << "Input your name: "; // buffered output! 
	cin  >> name;		// overflow of name!
	
	cout << "Your input: ";
	cout << name << endl;	
}

	

#include <iostream.h>
void main() 
{
	char name[10];
	char address[10];
	
	cin.tie(cout);// cout is flushed if cin needs input

	cout << "Input your name: ";  		
	cin  >> setw(sizeof(name)) >>name;						
	cout << "Your input: ";
	cout << name << endl;	

	cin.tie(0);	// unties cin and cout, makes cin faster
}

Declares basic io features

Do not use with stdio functions (scanf, etc)

Basic file io

io for arrays

Declares manipulators, which are values you insert into or extract from iostreams to have different effects

Allows use of iostreams (cin, cout) and stdio functions

Some compilers require that you call

cin.sync_with_stdio()

if you mix stdio functions (scanf, etc) with iostreams

For backward-compatibility only

ifstream

input file

ofstream

output file

fstream

input/output file

#include <iostream.h>
#include <fstream.h>

void main()
{ 
	fstream inputFile("test.cc", ios::in);

	if (!inputFile)
		cerr << "Could not open 'test.cc'";

	fstream outputFile("backup.cc", ios::out);

	if (!outputFile)
		cerr << "Could not open backup.cc'";

	char c;
	while (outputFile && inputFile.get(c)) 
		outputFile .put(c);
}

Open file at the end of the file

File is write only

Open file at the end of the file

Open file as read only

Open file as write only

if file already exists, delete contents

If file already exists, delete contents

If file does not already exists, open will fail

If file already exists, open will fail

#include <iostream.h>
#include <fstream.h>

void main()
{							       
	ifstream inputFile("test.cc");

	if (!inputFile)
		cerr << "Could not open 'test.cc'";

	ofstream outputFile("backup.cc");

	if (!outputFile)
		cerr << "Could not open 'backup.cc'";

	char c;
	while (outputFile && inputFile.get(c))
		outputFile.put(c);
}

#include <iostream.h>
#include <fstream.h>

void main()
{
	fstream readWriteFile("test.cc", 
						ios::in | ios::out);

	if (!readWriteFile)
		cerr << "Could not open 'test.cc'";
	
	readWriteFile.seekg(-10,ios::end);
	char x;
	readWriteFile >> x;
	cout << x;

	streampos here = readWriteFile.tellp();

	readWriteFile << "Hi mom";
	readWriteFile.seekg(here);	
}

• Class

• Object

• Inheritance

• Abstraction

• Encapsulation

• Information Hiding

• Hierarchy

Pattern: 	Priority queue

Essential Details:	length 
	items in queue 
	operations to add/remove/find item

Variation:	link list vs. array implementation
	stack, queue