Cloneable throws CloneNotSupportedException

Question

public class test implements Cloneable {
    @Override
    public test clone() {
        return (test) super.clone();
    }

    public static void main(String[] args) {
        new test().clone();
    }
}

I get error: unreported exception CloneNotSupportedException when I try to compile this (at line 4, not the main). As far as I can tell, the entire purpose of implementing Cloneable is to get rid of the exception.

• Is there a way to use super.clone() without throwing or catching the exception?
• Does the interface actually do anything?

Answer 1

Is there a way to use super.clone() without throwing or catching the exception?

No because Object#clone() (the method you are calling with super.clone()) declares it.

Does the interface actually do anything?

Yes, but very little: if you don't implement it, Object#clone() will actually throw the declared exception.

Answer 2

You need to handle CloneNotSupportedException exception, Class name should be start with capital letter.

Is there a way to use super.clone() without throwing or catching the exception?

If you don't want to handle exception inside clone method then use throws keyword it will propagate your exception to called method.

 public class Test implements Cloneable {
    @Override
    public Test clone() throws CloneNotSupportedException{
         return (Test) super.clone();
    }

    public static void main(String[] args) {
        try {
            new Test().clone();
        } catch (CloneNotSupportedException e) {
            e.printStackTrace();
        }
    }
}

Does the interface actually do anything?

public interface Cloneable

A class implements the Cloneable interface to indicate to the Object.clone() method that it is legal for that method to make a field-for-field copy of instances of that class. read more