Static Methods

static methods

Just like static variables, static methods also belong to the class. However there is no concept of having a separate copy of the method in case of methods though. When you declare a method static, you do not need to instantiate an object to access the static method of the class. You can directly invoke it using the class name. In the above example, method getNumberOfStudents can be declared static. The revised program would be:

class Student {

    static int numberOfStudents;

    private String name;

    public String getFirstName() {
        return this.name;
    }

    public void setFirstName(String name) {
        this.name= name;
    }

    public static int getNumberOfStudents() {
        return numberOfStudents;
    }

    public Student() {
        numberOfStudents++;
    }

    public static void main(String[] args) {
        Student student1 = new Student();
        student1.setFirstName("John");
        System.out.println(Student.getNumberOfStudents());
        Student student2 = new Student();
        student2.setFirstName("Jane");
        System.out.println(Student.getNumberOfStudents());
    }
}

Notice that you do not need the instance reference to invoke getNumberOfStudents method in the System.out.println statements.