Covariant Return Types


Problem Statement :


Java allows for Covariant Return Types, which means you can vary your return type as long you are returning a subclass of your specified return type.

Method Overriding allows a subclass to override the behavior of an existing superclass method and specify a return type that is some subclass of the original return type. It is best practice to use the @Override annotation when overriding a superclass method.

You will be given a partially completed code in the editor where the main method takes the name of a state (i.e., WestBengal, or AndhraPradesh) and prints the national flower of that state using the classes and methods written by you.

Note: Do not use access modifiers in your class declarations.

Resources
Covariant Return Type
Java Covariant Type

Input Format

The locked code reads a single string denoting the name of a subclass of State (i.e., WestBengal, Karnataka, or AndhraPradesh), then tests the methods associated with that subclass. You are not responsible for reading any input from stdin.

Output Format

Output is handled for you by the locked code, which creates the object corresponding to the input string's class name and then prints the name returned by that class' national flower's whatsYourName method. You are not responsible for printing anything to stdout.


Solution :



title-img 


                            Solution in C :

class Flower {
    private String message;
    
    public Flower(String message) {
        this.message = message;
    }
    
    public Flower() {
        this("I have many names and types");
    }
    
    String whats_Your_Name() {
        return this.message;
    }
}

class Jasmine extends Flower {
    public Jasmine() {
        super("Jasmine");
    }
}

class Lotus extends Flower {
    public Lotus() {
        super("Lotus");
    }
}

class Lily extends Flower {
    public Lily() {
        super("Lily");
    }
}

class State {        
    Flower your_National_Flower() {
        return new Flower();
    }
}

class WestBengal extends State {
    @Override
    Jasmine your_National_Flower() {
        return new Jasmine();
    }
}

class Karnataka extends State {
    @Override
    Lotus your_National_Flower() {
        return new Lotus();
    }
}

class AndhraPradesh extends State {
    @Override
    Lily your_National_Flower() {
        return new Lily();
    }
}








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