This document provides an overview of Java, including where it is used, classes and objects in Java, a simple Java program, and how it compares to C++. Java is an object-oriented, platform-independent language used for desktop, web, enterprise, mobile, and embedded applications. A class defines common attributes and behaviors of objects. A Java program contains a main method that is the entry point and gets compiled into bytecode then machine code when executed. The main difference between Java and C++ is that Java is platform independent while C++ is platform dependent.

1. core java
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2. content
Overview
Where Java used
Class
Object
Simple Java Program
Program execution
Java VS. C++

3. Overview
Java is an High-level, object oriented and platform
independent programming language. It was developed
by James Gosling.
There are 4 editions of Java
1. JavaSE (Java Standard Edition)
2. JavaEE (Java Enterprise Edition)
3. JavaME (Java Micro Edition)
4. JavaFX

4. Where Java used
Java is used in many places:
1. Desktop application
2. Web application
3. Enterprise application
4. Mobile application
5. Embedded System
6. Robotics
7. Games

5. class
a class is a collection of similar type of objects. It is a
logical entity. It is a template which represents
objects.
class
{
data;
methods;
}

6. object
An object is a real time entity that has state and
behavior. It is a physical as well as a logical entity.
For example, Pen is an object which has state (name,
color, size) and behavior (writing).

7. java program
class Demo
{
public static void main(String args[])
{
System.out.println("Hello");
}
}

8. Cont...
class: It is used to declare a class.
public:- It is access specifier. It makes the main
method visible to every where.
static: we don't have a need for any object to invoke
the main method.
void:- It is a return type. It means the main method
doesn't return any value.
String args[]: It is used for command line argument.

9. program execution
Java source code is converted into byte code by Java
compiler.
Java byte code is converted into machine code.
Compiler
Interpreter
Source
Code
Byte
Code
Byte
Code
Machine
Code

10. Java Vs. C++
The main difference between Java and C++ is that Java
is platform independent language and C++ is platform
dependent language.
Java doesn't support multiple inheritance, operator
overloading, Explicit pointers, Structures, Union
whereas C++ supports all these features.

11. thank you
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