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Static Variable

Static Variable:-A variable which is declared inside class, but outside method with static modifier called static variable. Static variables are used for memory saving purpose or providing facility. Static variable is a class level variable so every object can use static variable and access same value of that variable. So static variable is not related to particular object only. Any object can change the value of static variable and after change every object access new value of variable.static variables can access by two ways one is using the classname.variable and second is object.variable. Static variables can directly access in static method as well as non static method of class.

Example1:- Display default value directly.

class Student
{

static String instName;
public static void main(String[]args)
{
System.out.println(instName);
}
}

Output:-
C:\JAVATECH>javac Student.java
C:\JAVATECH>java Student
Null

Example2:- Display default value using class name.

class Student
{

static String instName;
public static void main(String[]args)
{
System.out.println(Student.instName);
}
}

Output:-
C:\JAVATECH>javac Student.java
C:\JAVATECH>java Student
Null

Example3:-Display default value using object.

class Student
{

static String instName;
public static void main(String[]args)
{
Student s=new Student();
System.out.println(s.instName);
}
}

Output:-
C:\JAVATECH>javac Student.java
C:\JAVATECH>java Student
Null

Example4:-Display initialize value directly.

class Student
{

static String instName="IIT Indore";
public static void main(String[]args)
{
System.out.println(instName);
}
}
Output:-
C:\JAVATECH>javac Student.java
C:\JAVATECH>java Student
IIT Indore

Example5:-object change the initialize value.

class Student
{
static String instName="IIT Indore";
public static void main(String[]args)
{
System.out.println(instName);
Student s=new Student();
s.instName=”IIM Indore”;
Student s1=new Student ();
System.out.println(s1.instName);

}
}

Output:-
C:\JAVATECH>javac Student.java
C:\JAVATECH>java Student
IIT Indore

IIM Indore
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