JDK 8 code review request for 8005298 Add FunctionalInterface type to the core libraries

[Joe Darcy]

PS The updated webrev is

     http://cr.openjdk.java.net/~darcy/8005298.1/

Thanks,

-Joe

On 01/08/2013 02:00 PM, Joe Darcy wrote:
> Hi Mike,
>
> On 01/08/2013 01:49 PM, Mike Duigou wrote:
>> Perhaps {@code} around java.lang.Object.
>
> Agreed.
>
>>
>> The default method and overriding Object method sentences could 
>> perhaps be said more simply:
>>
>> {@linkplain  java.lang.reflect.Method#isDefault() default methods} in 
>> interfaces do provide a method implementation and are not considered 
>> abstract.
>>
>> Interface methods which match methods of java.lang.Object are not 
>> considered abstract because an implementation (from java.lang.Object) 
>> is always available.
>>
>> Mostly it's enough to say that they aren't abstract. The part about 
>> abstract method count is superfluous.
>
> Okay; rewritten as:
>
>  * Conceptually, a functional interface has exactly one abstract
>  * method.  Since {@linkplain java.lang.reflect.Method#isDefault()
>  * default methods} have an implementation, they are not abstract. If
>  * an interface declares an abstract method overriding one of the
>  * public methods of {@code java.lang.Object}, that also does
>  * <em>not</em> count toward the interface's abstract method count
>  * since any implementation of the interface will have an
>  * implementation from {@code java.lang.Object} or elsewhere.
>
>>
>> @jls ref for default methods.
>
> That is actually included in the draft text of 9.4.3 and so is covered by
>
>  * @jls 9.4.3 Interface Method Body
>>
>> @jls ref for methods of Object.
>
> That is a good addition; I'll include
>
>  * @jls 4.3.2. The Class Object
>
> Thanks,
>
> -Joe
>
>>
>> On Jan 8 2013, at 13:24 , Joe Darcy wrote:
>>
>>> Hello,
>>>
>>> As discussed over on one of the Project Lambda lists [1], we're 
>>> adding an interface type to the platform to explicitly mark 
>>> interface types as being functional interfaces suitable for use in 
>>> lambda expressions.  Please review the addition of this new type:
>>>
>>>     http://cr.openjdk.java.net/~darcy/8005298.0/
>>>
>>> Follow-up work will add @FunctionalInterface annotations to 
>>> appropriate platform classes.
>>>
>>> Thanks,
>>>
>>> -Joe
>>>
>>> [1] 
>>> http://mail.openjdk.java.net/pipermail/lambda-libs-spec-experts/2012-December/000846.html
>