why am i able to call a static method using an object of that class ...

[Lalit Mehra]

why am i able to call a static method using an object of that class ... when it can only be called using the classname.methodName() format

  // testing the keyword super
// testing whether static methods can be overloaded and overridden
// testing if a static method can be called using the object and not the classname
// testing what happens if a class has two constructors private and public

package hfj;

import java.util.*;

class Animal {
	public Animal() {
		System.out.println("Inside Animal");	
	}
	
	private Animal(int i) {
		System.out.println("You are Inside Animal " + i);
	}
	
	public void getAnimal() {
		System.out.println("Animal");
		}
	
}

class Duck2 extends Animal {

	String name;
	
	public Duck2() {
		super();
		System.out.println("Inside Duck");	
	}
	
	public Duck2(String name) {
		//this();
		super();
		this.name = name;
	}

	public void getName() {
		System.out.println("Duck's name is: " + name);
	}	
	
	public static void quack() {
		System.out.println("quack! quack!");
	}
	
	public static void quack(int c) {
		int i=0;
		while(i++<c) {
		System.out.println("quack!");
		}
	}
	
	public void getAnimal() {
		System.out.println("Duck");
	}
}

public class Duck {
	
		public static void main(String [] args) {
			Duck2 d = new Duck2();
			d.getName();
			Duck2.quack();
			
			System.out.println();
			
			Duck2 d2 = new Duck2("soapy");
			d2.getName();
			d2.quack(4); // here it is 
			d2.getAnimal();
		}

}  

[Martin Vanyavchich]

Java looks up what type this object is (how it is declared) and calls that classes static function. Callig a static function on an object reference type works, but it's ... let's say bad coding. You could end up with somewhat upredictable results. See example below. Both objects in memory are actualy ducks, but it outputs

quack! quack!
sound! sound!

package javaranch;

import java.util.*;

class Animal {
  public static void makeSound() {
    System.out.println("sound! sound!");
  }
}

class Duck2 extends Animal {
  public static void makeSound() {
    System.out.println("quack! quack!");
  }
}

public class Duck {
  public static void main(String[] args) {
    Duck2 d = new Duck2();
    Animal a = new Duck2();

    d.makeSound();
    a.makeSound();
  }
}

[Lalit Mehra]

well ok ...

this means although we can use an object reference to call a static method we should not because in case we use polymorphic forms of reference variables that could create confusion ... i suppose this is all that you meant my friend

[Martin Vanyavchich]

Yes, that would sum it up

[Lalit Mehra]

hmmm ... even i was like "feeling the same" but as the book said you can only call a static method the classname.methodName() way so i went on to check it ...

thanks buddy ...

[Mike Simmons]

Lalit Mehra wrote:the book said you can only call a static method the classname.methodName() way

If a book said that, the book is definitely wrong.

Is it possible that the book said you should only call a static method that way? Because that's a matter of opinion, but it's an opinion I and many others agree with.

[Lalit Mehra]

ya Mike even i feel the same