Review request for 6810254

[Mandy Chung]

On 03/05/09 04:18, David Holmes - Sun Microsystems wrote:
> Hi Mandy,
> 
> Isn't this kind of change risky? With static initialization you know 
> that once the VM gets up and running then everything is in place. But 
> with lazy-initialization (and using reflection no less!) there's a 
> danger that when you try to initialize you're more likely to fail due to 
> lack of memory or resources.  

That's a good point. I change the getSystemShutdownHooks() method to 
return a preallocated array.  The initialization of the hooks themselves 
  are not changed by this fix.  However, if the application shutdown 
hook adds the first file to be deleted on exit, the lazy initialization 
may cause some trouble.  I'll look into it and send out a new webrev.

I ran the jtreg tests and I am going to run the JCK tests to make sure 
no regression.

> I can't quite tell exactly when these 
> setSharedSecret methods will be called.

When SharedSecrets.getJava*Access() method is called, it will 
SharedSecrets.setSharedSecret() which in turn calls 
<cls>.setSharedSecret() method of the given cls.

> BTW I think the comments copied into 
> src/share/classes/java/io/DeleteOnExitHook.java need to be reviewed - 
> they made sense when the code was java.io.File, but not now :)

Ok.

Thanks
Mandy

> Cheers,
> David
> 
> Mandy Chung said the following on 03/05/09 17:01:
>> 6810254: Lazily instantiate the shared secret access objects
>>
>> Webrev at:
>>   http://cr.openjdk.java.net/~mchung/6810254/webrev.00/
>>
>> sun.misc.Java*Access objects are created at initialization time.  
>> However, they are not always needed.  They can be instantiated lazily 
>> when needed.  The fix is to add a static setSharedSecret() method to 
>> be called by sun.misc.SharedSecrets via reflection when the shared 
>> secret access object is requested.
>>
>> Thanks
>> Mandy