RFR: [performance] Early class initialization from LambdaMetafactory improves lambda linkage performance

[Sergey Kuksenko]

Hi Remi,

ReflectiveOperationException is checked exception. Moving it into
PrivilegedAction requires to use PrivilegedExceptionAction, catching
PrivilegedActionException and rethrowing the exception. I don't think
that such code will be simpler than existing.
I am returning array of constructors because of I want don't change a
source of exception and do constructors check outside PrivilegedAction.


On 09/11/2013 09:43 PM, Remi Forax wrote:
> On 09/11/2013 07:14 PM, Aleksey Shipilev wrote:
>> On 09/11/2013 08:23 PM, Sergey Kuksenko wrote:
>>> http://cr.openjdk.java.net/~skuksenko/jsr335/8024633/webrev.00/
>> Looks good. (Not the Reviewer).
>>
>> -Aleksey.
>>
>>
> 
> you can simplify the code a little, you don't need to check the length 
> of the array twice,
> and the privileged action can return only the constructor instead of the 
> array
> avoiding to access the first element twice.
> 
> if (invokedType.parameterCount() == 0) {
>      final Constructor constructor = AccessController.doPrivileged(
>          new PrivilegedAction<Constructor[]>() {
>              @Override
>              public Constructor[] run() {
>                  Constructor<?>[] constructors = innerClass.getDeclaredConstructors();
>                  if (constructors.length != 1) {
>                      throw new ReflectiveOperationException("Expected one lambda constructor for "
>                           + innerClass.getCanonicalName() + ", got " +constructors.length);
>                  }
>                  Constructor constructor = ctrs[0];
>                  // The lambda implementing inner class constructor is private, set
>                  // it accessible (by us) before creating the constant sole instance
>                  constructor.setAccessible(true);
>                  return constructor;
>              }
>          });
>      Object instance = constructor.newInstance();
>      return new ConstantCallSite(MethodHandles.constant(samBase, instance));
> 
> I've let the 'final' in front of of the declaration constructor (line 2) 
> even final is not used
> for the declaration of other local variables and add in my opinion only 
> noise.
> 
> Rémi
> 
> 


-- 
Best regards,
Sergey Kuksenko