JDK 9 RFR of JDK-5040830: (ann) please improve toString() for annotations containing exception proxies

[Joel Borggrén-Franck]

Ping!

If the slightly irregular format wasn't intentional I think it is
worth taking a second pass over this before the toString gets set in
stone.

On Wed, Jun 1, 2016 at 8:33 PM, Joel Borggrén-Franck
<joel.borggren.franck at gmail.com> wrote:
> Hi Joe,
>
> I noticed you chose the old format for a type mismatch ("class java
> ...") and print the type name in the middle of the comment instead of
> before, why?
>
> Other than that, looks good!
>
> cheers
> /Joel
>
> On Tue, May 31, 2016 at 9:43 PM, joe darcy <joe.darcy at oracle.com> wrote:
>> Hello,
>>
>> Some background, when everything is going well, the toString form of an
>> annotation looks something like
>>
>> // Old non-erroneous annotation
>>
>> @DangerousAnnotation(utopia=BRIGADOON,
>> thirtyTwoBitsAreNotEnough=42,
>> classy=interface Fleeting,
>> classies=[class java.lang.Object, int],
>> moreClassies=[])
>>
>> with newlines added for clarity. However, there are various kinds of
>> problems that can occur with the data in an annotation and in those cases an
>> exception proxy is created so that if the corresponding method is called an
>> exception is thrown rather than the data being returned. In these cases the
>> string form of an annotation with
>> exceptions-that-would-be-thrown-if-methods-are-called looks like:
>>
>> // Current erroneous annotation
>>
>> @DangerousAnnotation(utopia=sun.reflect.annotation.EnumConstantNotPresentExceptionProxy at 766a8c91,
>> thirtyTwoBitsAreNotEnough=sun.reflect.annotation.AnnotationTypeMismatchExceptionProxy at 1f40866a,
>> classy=sun.reflect.annotation.TypeNotPresentExceptionProxy at 3de4f72b,
>> classies=[class java.lang.Object, int],
>> moreClassies=[])
>>
>> Having the proxy implementation leak through to the string representation in
>> this case is not helpful and the string can be made more informative. In
>> addition, for Class-related values, the current form doesn't use the syntax
>> which is legal in source code for annotations. Class-valued annotations are
>> set using Class literal syntax, "Foo.class" rather than "class Foo", and
>> arrays of Class-valued item should use braces ("{}") rather than brackets,
>> ("[]").
>>
>> For example, it would be better to have annotation string representations
>> which looked like:
>>
>> // New non-erroneous annotation
>>
>> @DangerousAnnotation(utopia=BRIGADOON,
>> thirtyTwoBitsAreNotEnough=42,
>> classy=Fleeting.class,
>> classies={java.lang.Object.class, int.class},
>> moreClassies={})
>>
>> // New erroneous annotation
>>
>> @DangerousAnnotation(utopia=BRIGADOON /* Warning: constant not present! */,
>> thirtyTwoBitsAreNotEnough=/* Warning type mismatch! "class
>> java.lang.Integer[42]" */,
>> classy=Fleeting.class /* Warning: type not present! */,
>> classies={java.lang.Object.class, int.class},
>> moreClassies={})
>>
>> Please review the code to implement these behavioral changes:
>>
>>     5040830: (ann) please improve toString() for annotations containing
>> exception proxies
>>     http://cr.openjdk.java.net/~darcy/5040830.2
>>
>> (If you have erroneous Class-value items in an array of Class values, then
>> this throws an exception since the exception proxy cannot be stored into the
>> Class[].)
>>
>> Thanks,
>>
>> -Joe
>>