RFR: 8338596: Clarify handling of restricted and caller-sensitive methods [v5]

[Maurizio Cimadamore]

On Mon, 23 Sep 2024 21:03:08 GMT, Maurizio Cimadamore <mcimadamore at openjdk.org> wrote:

>> This PR moves the section on restricted methods from the the javadoc of `java.lang.foreign` package into a standalone static [javadoc page](https://cr.openjdk.org/~mcimadamore/jdk/restricted_javadoc_section/docs/api/java.base/java/lang/foreign/doc-files/RestrictedMethods.html).
>> 
>> This is because, after [JEP 472](https://openjdk.org/jeps/472), we now have restricted methods *outside* the foreign package, namely `System::loadLibrary`, `Runtime::loadLibrary` (and related methods). And, even before, we also had a restricted method in `ModuleLayer.Controller`.
>> 
>> The new static page contains some guidance of what happens when a restricted method is called when there's no Java frame on the stack (this can happen e.g. when upcalling into a restricted method from a native thread not known to the JVM) - that is, the call is treated as originating from an unnamed module.
>> 
>> The static page is linked from the restricted method banner in a restricted method javadoc. Here's an [example](https://cr.openjdk.org/~mcimadamore/jdk/restricted_javadoc_section/docs/api/java.base/java/lang/foreign/Linker.html#downcallHandle(java.lang.foreign.MemorySegment,java.lang.foreign.FunctionDescriptor,java.lang.foreign.Linker.Option...)).
>
> Maurizio Cimadamore has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fix javadoc test failure

test/langtools/jdk/javadoc/doclet/testRestricted/TestRestricted.java line 45:

> 43:     public static void main(String... args) throws Exception {
> 44:         var tester = new TestRestricted();
> 45:         tester.setAutomaticCheckLinks(false);

@hns I had to disable this check because otherwise the test framework will attempt (and fail) to resolve `../java.base/java/lang/doc-files/RestrictedMethods.html`. Is there a better way to do this w/o disabling the link checks?

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/21067#discussion_r1772072696