introduction to oop with java - abu khleif |...

Introduction to OOP with Java - AKF Sep 2017

AbuKhleiF - www.abukhleif.com 1

Introduction to OOP with Java

Instructor: AbuKhleif, Mohammad Noor

Sep 2017

www.abukhleif.com

Introduction


Sep 2017

www.abukhleif.com

Lecture 01:

http://www.abukhleif.com/




Instructor

• AbuKhleif, ‘Mohammad Noor’• Studied Computer Engineer (JU 2012-2017)• Works as a Software Automation Engineer @ Atypon –

John Wiley and Sons Company - Jordan Branch

• Reach me at:• www.abukhleif.com• [email protected]• facebook.com/moh.noor94• twitter.com/moh_noor94

Course

• Java SE Basics• Object Oriented Programming• Course Page:

www.abukhleif.com/courses/java-101-sep-2017• Or, go to: www.abukhleif.com Courses Java 101 Course

– Sep 2017• Course Facebook Group:

www.facebook.com/groups/AKF2017Java


mailto:[email protected]

http://facebook.com/moh.noor94

http://twitter.com/moh_noor94

http://www.abukhleif.com/courses/java-101-sep-2017


https://www.facebook.com/groups/AKF2017Java/



Let’s Start!

Programs

• Computer programs, known as software, are instructions to the computer.

• You tell a computer what to do through programs. Without programs, a computer is an empty machine. Computers do not understand human languages, so you need to use computer languages to communicate with them.

• Programs are written using programming languages.



Programming LanguagesMachine Language

• Machine language is a set of primitive instructions built into every computer.

• The instructions are in the form of binary code, so you have to enter binary codes for various instructions.

• Program with native machine language is a tedious process.

• Moreover the programs are highly difficult to read and modify.

• For example, to add two numbers, you might write an instruction in binary like this:

1101101010011010

Programming LanguagesAssembly (Low Level) Language

• Assembly languages were developed to make programming easy.

• Since the computer cannot understand assembly language, however, a program called assembler is used to convert assembly language programs into machine code.

• For example, to add two numbers, you might write an instruction in assembly code like this: ADDF3 R1, R2, R3



Programming LanguagesHigh Level Languages

• The high-level languages are English-like and easy to learn and program.

• For example, the following is a high-level language statement that computes the area of a circle with radius 5:

area = 5 * 5 * 3.1415;

Java, 12.69%

C, 7.38%

C++, 5.57%

C#, 4.78%

Python, 2.98%

PHP, 2.21%

JavaScript, 2.02%

Visual Basic .NET, 1.98%

Perl, 1.95%

Ruby, 1.93%

R, 1.82%

Delphi/Object Pascal, 1.78%

Swift, 1.77%

Visual Basic, 1.75%

Assembly language, 1.64%

MATLAB, 1.63%

Go, 1.57%

Objective-C, 1.51%

PL/SQL, 1.48%

0.00%

2.00%

4.00%

6.00%

8.00%

10.00%

12.00%

14.00%

POPULAR HIGH-LEVEL LANGUAGES



Interpreting/Compiling Source Code

•A program written in a high-level language is called a source program or source code.

•Because a computer cannot understand a source program, a source program must be translated into machine code for execution.

• The translation can be done using another programming tool called an interpreter or a compiler.

Interpreting Source Code

• An interpreter reads one statement from the source code, translates it to the machine code or virtual machine code, and then executes it right away, as shown in the following figure:



Compiling Source Code

• A compiler translates the entire source code into a machine-code file, and the machine-code file is then executed, as shown in the following figure:

Why Java?

• You paid for a Java course

• It’s the current “hot” language

• Java enables users to develop and deploy applications on the

Internet for servers, desktop computers, and small hand-held

devices

• It’s platform independent• this makes it great for Web programming

• It has a vast library of predefined objects and operations



Why Java?

• Java is a general purpose programming language.

• Java is the Internet programming language.

• It’s almost entirely object-oriented

• It’s more secure

• It isn’t C++

Why Java?

• Java Is Simple

• Java Is Object-Oriented

• Java Is Distributed

• Java Is Interpreted

• Java Is Secure

• Java Is Portable• Please, read about Java characteristics here:www.cs.armstrong.edu/liang/JavaCharacteristics.pdf

http://www.cs.armstrong.edu/liang/JavaCharacteristics.pdf



Java Editions

Java Standard Edition (Java SE)

to develop client-side standalone applications or

applets.

Java Enterprise Edition (Java EE)

to develop server-side

applications.

Java Micro Edition (Java ME)

to develop applications for mobile devices.

JDK

• The Java Development Kit (JDK) consists of a set of separate programs, each invoked from command line, for developing and testing Java programs.

• Download Page:

www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html



JDK Versions

JDK 1.02 (1995)

JDK 1.1 (1996)

JDK 1.2 (1998)

JDK 1.3 (2000)

JDK 1.4 (2002)

JDK 1.5 (2004) a. k. a. JDK 5 or Java 5




JDK 1.9 (Coming in 2017) a. k. a. JDK 9 or Java 9

IDE

• The Integrated Development Kit (IDE) provides graphical user interface to edit, compile, build, and debug programs.

• Popular Java IDEs:

• NetBeans (Open Source)

• Eclipse (Open Source)

• IntelliJ IDEA (Free and Enterprise Editions)



Download IntelliJ IDEA

• Download Page: jetbrains.com/idea/download/

• Choose your OS (Windows?)

• Choose your version (Community?)

• Download!

• Want help? Please refer to this page:

www.jetbrains.com/help/idea/installing-and-launching.html

Welcome to Java

• Java source programs are case sensitive.• Every Java program must have at least one class.• Each class has a name. By convention, class names start with an uppercase

letter.• The main method is the entry point where the program begins execution.• A class may contain several methods. A method is a construct that contains

statements.

// This program prints Welcome to Java!

public class Welcome {

public static void main(String[] args) {

System.out.println("Welcome to Java!");

}

}

https://www.jetbrains.com/idea/download/

https://www.jetbrains.com/help/idea/installing-and-launching.html



Welcome to Java

• A pair of curly braces { } in a program forms a block that groups the program’s component.

• Every class has a class block that groups the data and methods of the class.

• Every method has a method block that groups the statements in the method.





}

}

Welcome to Java

• The System.out.println statement displays the string Welcome to Java on the console.

• A String is a sequence of characters. Strings should be enclosed in double quotation marks.

• Every statement in Java ends with a semicolon (;).• public, class, static, and void are reserved words : have a specific meaning to

the compiler and cannot be used for other purposes. In the program.





}

}



Welcome to Java

• Comments are ignored by the compiler.

• Two types of comments:

• Line comments: preceded by two slashes (//).

• Block (or paragraph) comments: enclosed between (/*) and (*/)

• Documentation comments: enclosed between (/**) and (*/)





}

}

Creating, Compiling,

and Running Programs





• Java source code is compiled into Java bytecode

• Your Java code may use the code in the Java library

• The bytecode is similar to machine instructions, but is architecture neutral and can run on any platform that has a Java Virtual Machine (JVM)

• The JVM is an interpreter, which translates individual instructions in the bytecode into the target machine language code and executes it immediately.



• Practically, you can do this on your PC using:• Any text editor to write and save your java file.

• DOS / Windows CMD / Linux Terminal / … to compile and run your program.

• To do that, refer to these links:• facweb.cs.depaul.edu/noriko/JavaSetup/

• stackoverflow.com/a/26693191

• But, believe me, you don't want this headache.

• Instead, let’s use IntelliJ IDEA

http://facweb.cs.depaul.edu/noriko/JavaSetup/

https://stackoverflow.com/a/26693191



Let’s Code

•Write a Java program that print your name and age to the console.

- Liang, Introduction to Java Programming 10/e- Eng. Asma Abdel Karim Computer Engineering Department, JU Slides- www.tiobe.com/tiobe-index


Sep 2017

www.abukhleif.com

References:

End of Lecture =D

https://www.tiobe.com/tiobe-index/


introduction to oop with java - abu khleif |...

Documents