Tuesday, June 16, 2020

Introduction To Java

JAVA

Computer & Programs :

Programing means to create a software which is contain the instructions that tell the computer or any other computerized device what to do , and this instructions called the program , so the program is a set of instructions that are telling the computer what to do , in order to do some tasks


         Computer is an electronic device that stores and processes data ,and it is consist of hardware and software

The hardware of the computer contain

A central processing unit (CPU) >> the computer’s brain and it’s contain of two main units ( the control unit which is coordinating the action , and the logic unit which is performs the numeric operations

Memory store the programs and its data

I/O devices

Communication devices , which are help the computer to networking and communicated with the other computers and computerized devices

Storage devices

The software which are the programs and software that are stored in the computer



Programing languages :

         The computer can’t understand the human language , so to make the human communicate with the computer they must use some language that the computer can understand

Machine Language : is the computer language that its instructions written in binary code just as 01101100

Assembly Language : Assembly language uses a short descriptive word, known as a mnemonic, to represent each of the machine-language instructions

Assembler : is a program that used to translate assembly-language program into machine code




Assembly Language known as low level programming language because it’s close in the nature to machine language & is machine dependent

High level programing languages

Start at 1950s

Platform dependent which means you can write your program and run it in different types of machines

Just as English text

EG : area =9*9*3.14159



High level programing language as

Java
++C
#C
python
C
Cobol
Pascal
Basic

Introduction to java

Java is a powerful and versatile programming language for developing software running on mobile devices, desktop computers, and servers.

developed by a team led by James Gosling in 1991 at Sun Microsystems. Sun Microsystems was purchased by Oracle in 2010 , was called Oak , and renamed to java at 1995

Java is a full-featured, general-purpose programming language

Java initially became attractive because Java programs can be run from a Web browser applets

The application program interface (API), also known as library, contains predefined classes and interfaces for developing Java programs ,and it’s still expanded

Java Development Toolkit is called JDK , set of separate programs, each invoked from a command line, for developing and testing Java programs

Instead of using the JDK, you can use a Java development tool (e.g., NetBeans, Eclipse, and TextPad) software that provides an integrated development environment (IDE) for developing Java programs quickly


to download textpad :

https://www.textpad.com/download/

to download JDK :

https://www.oracle.com/java/technologies/javase-jdk8-downloads.html

 

watch on YouTube


 

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