8361401: Warnings for use of Sun APIs should not be mandatory

[mcimadamore]

During Java 8, we changed the code that reported use of Sun API warnings (e.g. com.sun.misc.Unsafe) to use Log::mandatoryWarning instead of Log::strictWarning. This change had two effects:

• warnings for use of Sun API would not be emitted if more than 100 warnings were displayed
• warnings for use of Sun API would become mandatory warnings

The latter is particularly bad, because the definition of a mandatory warning is that of a warning mandated by the specification. Currently we only use the mandatory status for unchecked, deprecation and preview warnings.

This PR reverts the behavior to what it was before Java 8. That is, the warning for Sun API use is now marked with the STRICT flag -- and Log will not attempt to filter out warnings with such flag. As a result, the (unused) method Log::strictWarning can be removed.

I've tweaked an existing test to check the kind of the Sun API warnings.

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change requires CSR request JDK-8361402 to be approved

Issues

• JDK-8361401: Warnings for use of Sun APIs should not be mandatory (Bug - P4)
• JDK-8361402: Warnings for use of Sun APIs should not be mandatory (CSR)

Reviewers

• Jan Lahoda (@lahodaj - Reviewer)
• Vicente Romero (@vicente-romero-oracle - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/26129/head:pull/26129
$ git checkout pull/26129

Update a local copy of the PR:
$ git checkout pull/26129
$ git pull https://git.openjdk.org/jdk.git pull/26129/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 26129

View PR using the GUI difftool:
$ git pr show -t 26129

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Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/26129.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back mcimadamore! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

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[mcimadamore]

/csr

[openjdk]

@mcimadamore has indicated that a compatibility and specification (CSR) request is needed for this pull request.

@mcimadamore please create a CSR request for issue JDK-8361402 with the correct fix version. This pull request cannot be integrated until the CSR request is approved.

[mlbridge]

Webrevs

• 00: Full (e9362206)

[lahodaj]

Looks good to me.

[vicente-romero-oracle]

lgtm