JAVA - Global Variable

VARIABLES:

• In Java there are two types of variable

1. Global Variable

   -> Static Variable
   -> Non-Static Varible

2. Local Variable

Static variable:

• A static variable in Java is a class-level variable that is declared using the static keyword

• Static variable is used to store the class information.

• Unlike instance variables, only one copy of a static variable is created and shared among all objects of the class, making it useful for storing common data.
  

Public class Super{
Static string name="Murugan";
Static int addno=108;
public static void main(String[] args){
System.out.println(Super.name);
System.out.println(Super.addno);
}
}

Output:
Murugan
108

Static variables take single memory space for the whole class

OBJECT:

• In Java Object is a instance of a class

• It represents a specific entity created from the class template.

Public class Super{
Static string name="Murugan";
String pro_name="Laptop";
int price=25000;
Static int addno=108;
public static void main(String[] args){
Super product=new Super();   ---------------> This is the object creation 
System.out.println(Super.name);
System.out.println(Super.addno);
}
}

• In Object creation it will allocate the space for the some product in the supermarket

• Object is a Non- Static Information used to store the object information

What is field ?

• In java field is a global variable

if we assign variable in the main method is a local variable otherwise it is a global variable

• In java we doesnot assign any value for the variable means it will take a default value as 0

String=null
int=0
double=0.0
boolean=false

example:

Public class Super{
Static string name= "Murugan"
string pro-name;
int addno;
Public Static void main (String[] args){
Super product1=new Super();
Super product2=new Super();
product1.pro_name="Boost";
product1.price=250;
product2.pro_name="soap";
product2.price=300;
}
}

Output:
Boost
250
soap
300

When we create a object means it will take one memory space if we create another object means it will take another memory space.

so non-static variabes are the object information
Static variables are the class information