Co-variant Return Type - Part 1

I'm sharing my experience with you as these are the questions which have been asked to me while interviewing on java profile.
  
What is Covariant return type in java?

It means when one overrides a method, the return type of the overriding method is allowed to be same return type of overridden method or subtype of the overridden method's return type. From the release of JDK 1.5, covariant types were introduced in java.

Here is a simple example:

public class Human {
 
    protected Language speak() {
 
        return new Language();
    }
}
Dog class
public class Man extends Human{
 
    protected Language speak() {
        return new Hindi();
    }
}
It's possible to modify the return type of the Man's speak() method to Hindi- a sub class of Language, as shown below:

protected Hindi speak() {
 
    return new Hindi();
}
That's perfectly a legal overriding, and the return type of Man's speak() method is know as Covariant return type.


If you still have any question you can reach me any time through email (jigyasu2010@hotmail.com)

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