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Posted on    March-26-2015 12:06 AM

 Java Java 
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Mayank Tripathi
Mayank Tripathi

Total Post:807

Posted on    March-26-2015 12:54 AM

If you declare any variable as static, it is known static variable.

  • The static variable can be used to refer the common property of all objects (that is not unique for each object) e.g. company name of employees,college name of students etc.
  • The static variable gets memory only once in class area at the time of class loading.
  • It makes your program memory efficient (i.e it saves memory)

  1. class Student{  
  1.      int rollno;  
  1.      String name;  
  1.      String college="ITS";  
  1. }  

Suppose there are 500 students in my college, now all instance data members will get memory each time when object is created.All student have its unique rollno and name so instance data member is good.Here, college refers to the common property of all objects.If we make it static,this field will get memory only once.
  1. //Program of static variable  
  1. class Student8{  
  1.    int rollno;  
  1.    String name;  
  1.    static String college ="ITS";  
  1.    Student8(int r,String n){  
  1.    rollno = r;  
  1.    name = n;  
  1.    }  
  1.  void display (){System.out.println(rollno+" "+name+" "+college);}  
  1.  public static void main(String args[]){  
  1.  Student8 s1 = new Student8(111,"Karan");  
  1.  Student8 s2 = new Student8(222,"Aryan");  
  1.  s1.display();  
  1.  s2.display();  
  1.  }  
  1. }  
Output:111 Karan ITS
       222 Aryan ITS

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