1. Programming
Basic Concepts
© Juhani Välimäki 2003

2. Learning Goals
General principles, that help to create robust, understandable programs that are easy to modify
Solving problems with the programs
Using flowcharts to describe the logic of a program
Basic Java programming
© Juhani Välimäki 2003

3. What is Programming? Problem solving
Designing a program that will solve the problem
Reusing ready software components
Writing new code
Testing the program
Documentating and Creating User guides
© Juhani Välimäki 2003

4. Software Engineering The Waterfall Model Feasibility study
Requirements
Design
Implementation
Testing
Installation
aka. Deployment
Maintenance
© Juhani Välimäki 2003

5. What is a Program? data storage data storage program = program flow +
data processing rules
input
output
© Juhani Välimäki 2003

6. What is an Application?
Program and Application may usually be used as synonyms.
Application might be better term e.g. while referring to programs that have Graphical User Interface (GUI). Then ready-made UI components are applied to our own program. Or capabilities of the operating system are applied to certain problem solution.
Sometimes programs are called as software. ”This sofware is used to create CD-ROMs.”
© Juhani Välimäki 2003

7. What is a Programming Language 1?
Text Editor
With the text editor (Notepad, TextPad) programmer...
C++ source code
understood by the
programmer Hello.cpp
...writes source code, which is exact text description
of the program flow understood by the programmer
C++ -language compiler
for Linux and IBM 386 PC
Compiler is a program that understands the source
code written by the programmer and ...
A program understood by the
Linux operation system and
the IBM 386 PC computer
= bit flow
... knows how to create an executable program
that is nonsense to programmer...
...but works in a certain machine and operating
system, referred as the running environment.
Linux operating system
in an IBM 386 PC
© Juhani Välimäki 2003

8. What is a Programming Language 2?
Java source code
understood by the
programmer Hello.java
Text Editor
Virtual Machine makes it possible to run the same program on different computers and operating systems
Java Byte Compiler
for Java Virtual Machine
Hello.class
A program Java Virtual Machine
understands
Java Virtual Machine (Java VM)
for Windows
Java VM
Java VM
Java Virtual Machine
for Linux
Windows Operating System
Mac
Symbian
Linux Operating System
© Juhani Välimäki 2003

9. What is the Source Code? source code understood by the Text Editor
programmer
Text Editor
// Example of Java source code
import java.util.*;
public class OwnApplication {
static public void main()
int result = 0;
int sum = 0; …
sum = sum + value;
{Example of Pascal source code} …
begin
result :=0;
sum :=0;
readln (value);
if (value>0) then
sum := sum + value;
end.
© Juhani Välimäki 2003

10. Do You Remember these Concepts?
Programming
Program (≈ Application ≈ Software)
Input, output. (=IO)
Programming Language
Source Code
Compiler
Operating System
Java
Java Byte Compiler
JavaVirtual Machine
© Juhani Välimäki 2003