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Q) Explain about static method?




A)

->if we apply static modifier to the instance method of a class, it becomes a static method or class method.
Static void display ();

->static method can be called with class name as well as object name.
->Sometimes object creation is unnecessary but still some processing should be done by providing a method, static method is the choice.
->without the need of object a static method can be called directly with class name.
->static method is not the behaviour of the object. These are 2 restrictions in the usage of static method.
1.”this” keyword can’t be used.
2. Instance variable and methods can’t be referred (without object creation).
classstaticexample1 {

       static int a;
       int b;
       void x()
       {
              a=80;
       }
       void y()
       {
              x();
              z();
              //allowed
              //here reference is not required.
              //because calling method being to the same object class.
       }
       static void z()
       {
              //not allowed
              b=60;//inside static method you can't refer instance variable.
              y();//non static method y() can't be referred by static content.
             
             
             
       }
       static void Z()
       {
              a=60;
              staticexample1 a=new staticexample1();
              a.y();//we can refer inside static method by creating the object.
       }

}


class staticexample2 {
      
       static int a;
       int b;
       void x()
       {
              a=80;//ok
       }/*  calling method and called method belong to the same object
              *reference not required to call the instance method.
              */
       void y()
       {
              x();
              z();
       }
       static void z()
       {
              b=60;//not ok
              y(); /*   not ok
                            * without object creation
                            * instance method can't be called from static method.
                            */
       }
}

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