Java Introduction

What is Java?

• Java is a high-level,object oriented programming language developed by sun microsystems.
• It is mostly used for building web applications.
• It is platform independent,because we can write it once,it will run on any device if jvm is installed

Why object-oriented?

Java is object oriented because it focuses on the concept of object and supports encapsulation,inheritance,polymorphism and abstraction.

Core concepts of Java Ecosystems
JDK = JRE + Development Tools
JRE = JVM + Libraries

• Compiler translates the human readable code to machine readable code.
• That compiler consists of multiple set of software known as Java Development KIT.
• We save that java file using .java after that byte code will save that file as .class
• Java virtual machine,converts Java bytecode (compiled code) into machine code.
• It is the intermediate between java code and hardware.
• The JIT or Just-In-Time compiler converts bytecode into native machine code at runtime.

Example Java Code

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