exception doubt

[dolly shah]

public class Test20 extends A3{
    Test20()throws Exception{
        System.out.println("Test10 Class");
    }
    Test20(int i){}
    public static void main(String args[]) throws Exception{
        Test20 t = new Test20();
    }
}
class A3{
    A3() throws Exception{
        System.out.println("A Class");
    }
}

What will be the output?
A1 A Class Test10 Class
A2 Runtimxception
A3 no output
A4 Compiler Error -answer

Why compiler error shows me at "Test20(int i){}" unhandled exception?
Can anybody explain?

[christian combarel]

Hi,
If you instanciate Test20 using the Test20(int i){} constructor, the A3() will be called. As A3() declare an Exception, it must be declared too with Test20(int i){}.

[dolly shah]

If you instanciate Test20 using the Test20(int i){} constructor. That means what? What you want to say I am not getting. Can you explain little more?

[Praveen Seluka]

Hi

If a superclass constructor throws Exception,then whether subclass constructor should also declare throws Exception

Thanks
Praveen SP

[Lucky J Verma]

Test20(int i ) constructor will call Parent class A3's no-arg constructor ,unless super is mentioned
A3() constructor throws Exception ,so caller method must also have a way to handle the exception.
In case A3() has no-exception clause,it wolud have run.

[Praveen Seluka]

Thanks Lucky verma,I got it.