A variable provides us with named storage that our programs can manipulate. Each variable in Java has a specific type, which determines the size and layout of the variable's memory; the range of values that can be stored within that memory; and the set of operations that can be applied to the variable.
Static Variable
A static variable is also called a class variable and is common across the objects of the class and this variable can be accessed using class name as well.
Non-Static Variable
Any variable of a class which is not static is called non-static variable or an instance variable.
Following are the important differences between static and non-static variable.
| Sr. No. | Key | Static | Non-Static |
|---|---|---|---|
| 1 | Access | A static variable can be accessed by static members as well as non-static member functions. | A non-static variable can not be accessed by static member functions. |
| 2 | Sharing | A static variable acts as a global variable and is shared among all the objects of the class. | A non-static variables are specific to instance object in which they are created. |
| 3 | Memory allocation | Static variables occupies less space and memory allocation happens once. | A non-static variable may occupy more space. Memory allocation may happen at run time. |
| 4 | Keyword | A static variable is declared using static keyword. | A normal variable is not required to have any special keyword. |
Example of static vs non-static variable
JavaTester.java
public class JavaTester {
public int counter = 0;
public static int staticCounter = 0;
public JavaTester(){
counter++;
staticCounter++;
}
public static void main(String args[]) {
JavaTester tester = new JavaTester();
JavaTester tester1 = new JavaTester();
JavaTester tester2 = new JavaTester();
System.out.println("Counter: " + tester2.counter);
System.out.println("Static Counter: " + tester2.staticCounter);
}
}Output
Counter: 1 Static Counter: 3