CodeGym/Help with Java Tasks/using instanceof and it was correct for all except lion a...

Level 15

Delhi

11.10.2018
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using instanceof and it was correct for all except lion and Tiger.Please help

Question about the task

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package com.codegym.task.task12.task1225; /* Visitors */ public class Solution { public static void main(String[] args) { System.out.println(getObjectType(new Cat())); System.out.println(getObjectType(new Tiger())); System.out.println(getObjectType(new Lion())); System.out.println(getObjectType(new Bull())); System.out.println(getObjectType(new Cow())); System.out.println(getObjectType(new Animal())); } public static String getObjectType(Object o) { //write your code here if(o instanceof Cat) return "Cat"; else if ( o instanceof Tiger) return "Tiger"; else if (o instanceof Lion ) return "Lion"; else if (o instanceof Bull) return "Bull"; else if (o instanceof Cow) return "Cow"; else return "Animal"; } public static class Cat extends Animal // <-- Class inheritance! { } public static class Tiger extends Cat { } public static class Lion extends Cat { } public static class Bull extends Animal { } public static class Cow extends Animal { } public static class Animal { } }

Write a method that will determine the type of object passed to it.
The program should display one of the following:
"Cat", "Tiger", "Lion", "Bull", "Cow" or "Animal".

Note:
try to determine the type of animal as accurately as possible.

Requirements:

The Solution class must have Cat, Tiger, Lion, Bull, Cow, and Animal classes.
The Solution class must have a String getObjectType(Object o) method.
The getObjectType() method must return "Cat" if a Cat object is passed.
The getObjectType() method must return "Tiger" if a Tiger object is passed.
The getObjectType() method must return "Lion" if a Lion object is passed.
The getObjectType() method must return "Bull" if a Bull object is passed.
The getObjectType() method must return "Cow" if a Cow object is passed.
The getObjectType() method must return "Animal" if an Animal object is passed.
The program should display the result of calling the getObjectType() method.

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Onyejeme Emmanuel

Level 14

9 January 2021, 17:18

Check for the more specific classes before checking a general class i.e. Check for Tiger first Check for Lion second Then you can now check for Cat and the rest. Summary: Checking for Cat first returns true for Lion and Tiger objects because they are related

Nazim

Level 14 , Chennai, India

5 July 2020, 15:49

You Can use && inside the if loop to check o is an instance of both Tiger and Cat, then return the tiger Similarly if its a instance of both Cat and Lion return Lion, else only cat

Lawson

Level 29 , Lagos, Nigeria

24 August 2020, 14:49

pls is that what u did?

Serg

Level 17 , Minsk, Belarus

23 June 2019, 08:54

return o.getClass().getSimpleName();

Learner

Level 16 , India

11 October 2018, 11:16

Tiger and Lion classes are inherited from Cat class which means, even if the object is an instance of tiger or lion, it will return true for Cat. So, your first if statement will be true, and the program will return Cat. Try checking lion and tiger before Cat.

+14

Anoop Negi

Level 15 , Meerut, India

9 December 2018, 08:59

please give some hint

Hashirama

Level 26 , Port-Harcourt, Nigeria

4 February 2019, 02:15

OR you could do it this way: if (o instanceof Cat) if (o instanceof Tiger) return ........; else if (o instanceof Lion) return ......; else return ........;

Hashirama

Level 26 , Port-Harcourt, Nigeria

4 February 2019, 02:17

Please I have a question: why didn't it return true for Cat as an instanceof Animal since the Cat class also extends the Animal class, as well as the Bull class? Why did it only return true for Lion and Tiger as intancesof the Cat class?

Hashirama

Level 26 , Port-Harcourt, Nigeria

4 February 2019, 02:21

Never mind: I see it now. If we had checked: if (o instanceof Animal) for the new Cat() object, it would have returned true as well. I get it now...!!!

Khulekani

Level 16 , Durban, South Africa

17 March 2019, 02:23

I like this guy

SefoBe

Level 16 , Paris, France

9 October 2019, 21:16

Thanks for that ;)

Petros

Level 23 , Columbia, United States

3 August 2020, 02:23

Thank you! I get it. If it checks Cat first, then it won't pick up any sub (child) classes from Cat such as Lion and Tiger. Wow, beautiful. I really gotta study my butt off.