RFR: 8281057: Fix doc references to overriding in JLS

[David Holmes]

On 2/02/2022 10:46 pm, Pavel Rappo wrote:
> On Wed, 2 Feb 2022 12:06:39 GMT, David Holmes <dholmes at openjdk.org> wrote:
> 
>>> While looking into guts of javadoc comment inheritance, I noticed that a number of places in JDK seem to confuse JLS 8.4.6.** with JLS 8.4.8.**.
>>>
>>> Granted, "8.4.6 Method Throws" tangentially addresses overriding. However, I believe that the real target should be "8.4.8. Inheritance, Overriding, and Hiding" and its subsections.
>>
>> src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Check.java line 1793:
>>
>>> 1791:         }
>>> 1792:
>>> 1793:         // Error if static method overrides instance method (JLS 8.4.8.2).
>>
>> "overrides" should be "hides"
> 
> Although you seem to be correct, the error messages and the code around operate using the term "override":

Ah yes, I can see now that "overrides" is (incorrectly) used all through 
this code and even in the error messages. It is a subtle distinction.

Cheers,
David
-----

>          // Error if static method overrides instance method (JLS 8.4.8.2).
>          if ((m.flags() & STATIC) != 0 &&
>                     (other.flags() & STATIC) == 0) {
>              log.error(TreeInfo.diagnosticPositionFor(m, tree),
>                        Errors.OverrideStatic(cannotOverride(m, other)));
>              m.flags_field |= BAD_OVERRIDE;
>              return;
>          }
> 
>          // Error if instance method overrides static or final
>          // method (JLS 8.4.8.1).
>          if ((other.flags() & FINAL) != 0 ||
>                   (m.flags() & STATIC) == 0 &&
>                   (other.flags() & STATIC) != 0) {
>              log.error(TreeInfo.diagnosticPositionFor(m, tree),
>                        Errors.OverrideMeth(cannotOverride(m, other),
>                                            asFlagSet(other.flags() & (FINAL | STATIC))));
>              m.flags_field |= BAD_OVERRIDE;
>              return;
>          }
> 
> 
>          /**
>           * compiler.err.override.static=\
>           *    {0}\n\
>           *    overriding method is static
>           */
>          public static Error OverrideStatic(Fragment arg0) {
>              return new Error("compiler", "override.static", arg0);
>          }
> 
> Compiler folk, what do you think?
> 
> -------------
> 
> PR: https://git.openjdk.java.net/jdk/pull/7311