Quarkus REST: various issues with lastModified dates

[FroMage]

Describe the bug

• ResponseBuilder.lastModified will use whatever user-configured ParamConverter for Date, which is wrong, because HTTP date headers must be formatted in a special way, otherwise we will fail parsing them
• Calling Request.evaluatePreconditions(Date) is very likely to never work, because Date is millisecond-precision, whereas HTTP headers are second-precision, so there's 999/1000 chances that the date we're passed will be later than the (truncated) header, unless the user applies this truncation beforehand (and knows about it). We should truncate it ourselves, because we only operate on second-precision due to HTTP limitations.

Expected behavior

No response

Actual behavior

No response

How to Reproduce?

No response

Output of uname -a or ver

No response

Output of java -version

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Quarkus version or git rev

No response

Build tool (ie. output of mvnw --version or gradlew --version)

No response

Additional information

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[quarkus-bot]

/cc @stuartwdouglas (resteasy-reactive)

[FroMage]

Apparently, the problem is not ParamConverter<Date> because those are not used for headers, contrary to intuition, these are under the responsability of RuntimeDelegate.HeaderDelegate<Date>, and the problem is due to Hibernate generating Date values which are of a subclass of java.util.Date, and createHeaderDelegate(Class) is an exact match, so Object.toString() is used, which is invalid:

        } else if (type.equals(Date.class)) {
            return (HeaderDelegate<T>) DateDelegate.INSTANCE;
...
        } else {
            return (HeaderDelegate<T>) ObjectToStringDelegate.INSTANCE;
        }