2.Hello World in Java

 Introduction to Java :

Java is a Object Oriented Programming Language.We will use Java for Web Development and android apps development.Web development means building websites.Linkedin and Amazon are build their websites using Java Programming Language.Spotify and twitter are the examples of Android apps.

We should learn about some Key Terms :

1.JVM (Java Virtual Mechine) : JVM converts source code into bytecode.

The Code which we have written is Source Code. see the Example.

The Code which is generated by JVM through our source code is Byte Code. simply the compiled code is byte code.

 

  

 

 

 

2. Class :  Class is a blueprint of an Object.

for example if we want to construct an building, first we require blue print, that blue print is nothing but class.

3.Object : Object is an instance of Class.

After we have constructed what ever the output generated, (i.e building) is Object.simply if building is an object the blueprint which is used to construct a building is Class.

remember one Object has behavior and properties. If you take building as an object it has floors,rooms,doors all are these properties. we have many objects in real life.

 

 

 

These are all exaples for objects.Now lets write a hello world program.

Steps to run the Program :

1.go to the path where you have saved the File. I have saved on Desktop.Compile the code using javac filename (My file here is CodeMagic.java)

 

2.run the code using java class name and you can see the output

 

Congratulations you have done the first step......keep it up....