B&S: How to difference between my and JDK's SecurityException?

[Darya Akbari]

Hi all,

I have a problem with my SecurityException during compilation.

My data interface class DB.java looks like:

  
package suncertify.db;
 
public interface DB {
    ...
    public void update(int recNo, String[] data, long lockCookie) 
            throws RecordNotFoundException, [B]SecurityException[/B];
    ...
}

The implementing class Data.java looks like:

  
package suncertify.db;
 
import java.util.*;
 
public class Data implements DB {
    ...
    public void update(int recNo, String[] data, long lockCookie) 
            throws RecordNotFoundException, [B]SecurityException[/B] {
        ...
    }
    ...
}

Now, when I try to compile I get the error:

.\suncertify\db\Data.java:42: update(int,java.lang.String[],long) in suncertify.db.Data cannot implement update(int,java.lang.String[],long) in suncertify.db.DB; overridden method does not throw suncertify.db.SecurityException

How can I make sure that the compiler take my SecurityException (suncertify.db.SecurityException)
[ May 25, 2005: Message edited by: Darya Akbari ]

[Frans Janssen]

Hi Darya,

Probably your compiler assumes java.lang.SecurityException in your DB interface. I would not know how to prevent that, without making changes to the interface.
(I tried, but I cannot reproduce your error here.)

You might therefore consider not to create your own SecurityException class. According to the following statement you need not make exceptions that already exist:

Any unimplemented exceptions in this interface must all be created as member classes of the suncertify.db package.

Frans.

[Wei-ju Wu]

Hi Frans and Darya,

I just remembered this thread:

Security Exception

which relates to Darya's question. At that time it did not come to my mind that this could be another problem if java.lang.SecurityException is not used

So I guess the easiest way would really be to simply reuse the JDK exception.

Wei-ju
[ May 25, 2005: Message edited by: Wei-ju Wu ]

[Darya Akbari]

Hi Frans and Wei-ju,

I agree with you Frans that possibly we should use JDK's SecurityException but the following which Wei-ju is referring to Security Exception is still an open thread.

Since a security manager is the one who throws JDK's SecurityExcepion (java.lang.SecurityException) I stuck here because it's also said in the assignment that a security manager must not be used.

Nevertheless you both have passed SCJD and that is another reason to go for java.lang.SecurityException . But honestly I don't understand it

Regards,
Darya

[Lara McCarver]

.\suncertify\db\Data.java:42: update(int,java.lang.String[],long) in suncertify.db.Data cannot implement update(int,java.lang.String[],long) in suncertify.db.DB; overridden method does not throw suncertify.db.SecurityException

I am sorry for editting this so many times. As others have suggested, I would use Sun's implementation of SecurityException... what do you gain by making your own? If you do want to use your own, I think it would be OK to specify the precise exception within the interface method of your Data class:

update(...)
throws RecordNotFoundException, suncertify.db.SecurityException {
...}

If you do this, you are still using the DB interface... just clarifying what it means, but I don't think the clarification is actually changing the signature.
[ May 25, 2005: Message edited by: Lara McCarver ]

[Darya Akbari]

Hi Lara,

the only reason why I was going for my own SecurityException was because of the security manager issue as decribed in SecurityException

As Frans said, I don't dare to change the signature of the given data interface

Regards,
Darya

[Ken Boyd]

You can create SecurityException.java under suncertify.db and use that in Data.java class instead of java.lang.SecurityException...

anything wrong in doing that...

[Frans Janssen]

Nevertheless you both have passed SCJD and that is another reason to go for java.lang.SecurityException

My assignment's interface didn't have SecurityExceptions. So if I passed it, it is not because of my idea how to handle the SecurityException issue...

Frans.

[Frans Janssen]

Back to your original problem: which compiler are you using? Because according to the Java language specification, the compiler should use your SecurityException in both the interface and the Data class.

I tried the JBuilder compiler and Sun's compiler, but with neither can I reproduce your compiler error.

Frans.

[Darya Akbari]

Hi Frans,

don't ask me why the heck it now compiles. I changed code back and fore and can't now reproduce the error by myself

So my own SecurityException is back in place and my doubts on JDK's SecurityException either

Thanks spending your time on the issue.

Regards,
Darya