Java begin so we win

JAVA Begin So We WinBy Eng : Mohamed Mahmoud Youssef

JAVA Begin SO We Win

By : Mohamed Mahmoud Youssef

Agenda 1- JAVA , What ?!!

2- JAVA , Why ?!!3- JAVA , When ?!! 4- JAVA slow ?!!5- JAVA editions ...6- JAVA , How ?!!7- let us go …

• James Gosling- Gosling left IBM in 1984 to join

Sun, first he chose C++. But he

soon gave up on C++ .

- Then he started to modify C++ .

- Then created JAVA .

1- JAVA , What ?!!

* - JAVA is a computer programming language created by Sun Microsystems which become apart of oracle company .

1- JAVA , What ?!!

* - JAVA is more than programming language it is technology .

2- JAVA , Why ?!!1- Similar to C++ so it is familiar to commercial programmers.

2- OOP language .3- platform independent .4- Has garbage collector .5- multithreaded .6- Dynamic . 7- more security than C&C++ .8- JAVA is technology . 9- open source .

2- JAVA , Why ?!!

1- Similar to C++ so it is familiar to commercial programmers.

2- JAVA , Why ?!!

2- OOP language .

2- JAVA , Why ?!!

3- platform independent .

JAVA Prog

Compiler

JVM JVM JVM JVM

MAC MVS UNIX Windows

The JVM …

Non-virtual Machine Virtual Machine

2- JAVA , Why ?!!

4- Has garbage collector .

2- JAVA , Why ?!!

5- multithreaded .

2- JAVA , Why ?!!

6- dynamic .

2- JAVA , Why ?!!

7- more security than C&C++ .

High security* - To write java program :1- write in a Text Editor .2- compiler creates bytecode .3- “ class loader “ places the ( .class file ) in memory .4- “ byetcode verifer “ makes sure the code adhere to the rules

of java security .5- The “JVM” interpreter reads bytecode and makes platform

native code .

PrimaryMemory

.

.

.

.

.

.

Disk

Disk

Disk

Editor

Compiler

Class Loader

Program is created in an editor and stored on disk in a file ending with .java.

Compiler creates bytecodes and stores them on disk in a file ending with .class.

Class loader reads .class files containing bytecodes from disk and puts those bytecodes in memory.

Phase 1

Phase 2

Phase 3

PrimaryMemory

.

.

.

.

.

.

Bytecode Verifier Bytecode verifier confirms that all bytecodes are valid and do not violate Java’s security restrictions.

Phase 4

PrimaryMemory

.

.

.

.

.

.

InterpreterInterpreter reads bytecodes and translates them into a language that the computer can understand, possibly storing data values as the program executes.

Phase 5

2- JAVA , Why ?!!

8- JAVA is technology .

Problem

JAVA programming language

JDK

JAVA deployment tools

JAVA Runtime Environment

Program So JAVA is tech

2- JAVA , Why ?!!

9- open source .

3- JAVA , When ?!!

*- At any time .

4- JAVA , slow !!!

* - JIT compiler .

* - JIT actually takes your byte code and translated it into native code

This translated code will run just as fast as any C++ program .

5- JAVA Editions …

* - when java was introduced it primaly consists of two components

i- programming language specification . ii- JRE specification .

* - They described the JVM .

5- JAVA Editions …*- when java evolved sun added new specifications and techs that

made java more than a programming language .

* For example *

- Servlets and JSP provided to create dynamic web pages . - EJB (enterprise java beans) provided for developing distributed

applications .And more adds which make java more than programming language .- RMI .

5- JAVA Editions …

*- Sun grouped java editions into

1- JAVA SE .2- JAVA EE .3- JAVA ME .

6- JAVA , How ?!!*- requirements …

1- Editor :

- Notepad .- Notepad++ .- Textpad++ .- Jext .- Jedit .- Eclipce .- Net beans .- Jcreator .

2- JAVA compiler (JDK) .

http://www.sun.com

http://www.oracle.com/us/sun/index.html

7- Let us go …

*- Simple programs

• So begin to win

Development of the mind

Pride

Money

Q & A

Thanks a lot

Eng : Mohamed Mahmoud Youssef .

E-mail : mailto:ITHawye@gmail.com

GOoOdeBye To TOP …