confused in runtime exception and compile time exception

[Prakash Mahto]

Hi,
I am confused in CTE and RTE?
If exam question ask about which type of exception is this, so how should i answer it?

Thanks

[T. Huy Nguyen]

Imagine you build and run the code: if you encounter compilation error, it's CTE. Else, if you encounters error/exception when you run it, it's RTE.

[Prithvi Sehgal]

Hello, Prakash,

First, please use the full form of words, as it gets difficult for the reader to understand your short hand. It's against
javaranch policy.

Well, for the question as you have asked, you got to be aware that what kind of checked exception will be thrown and case compile time error.
For example, if an object reference is null and you try to invoke some method over it, you will get a NullPointerException which
is a run-time exception. On other hand if you are use parse function from the Date class, it shows a checked exception so if you
forget to handle it or throw it, the compiler will generate a compile time error. So you need to understand the situations yourself
to acquaint yourself with such scenarios.

Hope this helps,

[Ankit Garg]

There is runtime exception and compile time error but no compile time exception. I hope you are not talking about checked and unchecked exceptions here (one has to be handled for the code to compile, one is not)...

[Sunny Bhandari]

Yes he looks to be talking about checked and unchecked exceptions.

[Prakash Mahto]

Hi, prithvi
Sorry to reply late and putting short form
It seems that it is completely on practice and self feeling to know about the differnece between compile time error and run time exception.

is there any specific list for OCPJP exam which separate these both

Thanks

[Prakash Mahto]

thanks Ankit for improving my mistake on Compile time Error not Exception

[Deepak Bala]

(one has to be handled for the code to compile, one is not)

Just to nitpick Ankit and arise his ire, an unchecked exception can always be thrown and not handled.

import java.io.FileWriter;

class Cert
{
    public static void main(String... args) throws Exception
    {
        new Cert().go();
    }

    public void go() throws Exception
    {
        FileWriter fileWriter = new FileWriter("");
    }
}  

of course by handled, Ankit meant that it should be thrown or caught. Just so it is clear to someone that stumbles on this thread later on.

[Javin Paul]

Hi Prakash,

Every Exception class is derived from Throwable e.g. Error and Exception , any exception which is subclass of Exception but not subclass of RuntimeException its known as "Checked Exception" and has to be handled (either using try-catch or throws) at compile time , means if you won't provide proper code compiler will complain.

on the other hand any exception which is subclass of RuntimeException are not checked by compiler at compile time.

e.g. IOExcepiton is a checked exception (not subclass of RuntimeExcepiton) and NullPointerException is unchecked exception(subclass of RuntimeException).

hope this helps.