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<p>Hi, some answers below:</p>
<p>(1) refers to the ability to query what primitive layouts are
like, using Linker::canonicalLayouts.<br>
See:
<a class="moz-txt-link-freetext" href="https://docs.oracle.com/en/java/javase/22/docs/api/java.base/java/lang/foreign/Linker.html#canonicalLayouts()">https://docs.oracle.com/en/java/javase/22/docs/api/java.base/java/lang/foreign/Linker.html#canonicalLayouts()</a></p>
<p>(2) refers to the new methods in MemoryLayout, namely
MemoryLayout::scale/scaleHandle, together with the fact that now
all var handles generated by this API take a start offset (so they
are easier to combine).<br>
see:
<a class="moz-txt-link-freetext" href="https://docs.oracle.com/en/java/javase/22/docs/api/java.base/java/lang/foreign/Linker.html#canonicalLayouts()">https://docs.oracle.com/en/java/javase/22/docs/api/java.base/java/lang/foreign/Linker.html#canonicalLayouts()</a><br>
<br>
(3) refers to the fact that you can now read and write strings
with more charsets than just UTF8. You can now use any charset in
StandardCharsets (to which we have added UTF32, for good measure).<br>
see:
<a class="moz-txt-link-freetext" href="https://docs.oracle.com/en/java/javase/22/docs/api/java.base/java/lang/foreign/MemorySegment.html#getString(long,java.nio.charset.Charset)">https://docs.oracle.com/en/java/javase/22/docs/api/java.base/java/lang/foreign/MemorySegment.html#getString(long,java.nio.charset.Charset)</a><br>
</p>
<div class="moz-cite-prefix">Maurizio<br>
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<div class="moz-cite-prefix">On 07/06/2024 23:30, Cheng Jin wrote:<br>
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<blockquote type="cite" cite="mid:SJ2PR15MB5689C36C5751FA14ACB6E9A5F5FB2@SJ2PR15MB5689.namprd15.prod.outlook.com">
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<p class="MsoNormal"><span style="font-size:11.0pt">Hi there, <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I’ve got a
question about JEP454 at <a href="https://openjdk.org/jeps/454" moz-do-not-send="true" class="moz-txt-link-freetext">https://openjdk.org/jeps/454</a>
in which some of refinements confused me as follows:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<ol style="margin-top:0cm" type="1" start="1">
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><i><span style="font-size:11.0pt">Enabled clients to build
C-language function descriptors programmatically,
avoiding platform-specific constants;<o:p></o:p></span></i></li>
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><i><span style="font-size:11.0pt">Improved support for
variable-length arrays in native memory;<o:p></o:p></span></i></li>
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><i><span style="font-size:11.0pt">Added support for arbitrary
charsets for native strings.<o:p></o:p></span></i></li>
</ol>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I didn’t
find any description in the JEP to clarify how they work and
what they mean to users.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Could
anybody explain these refinements in more details? Many
thanks.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Best Regards<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Cheng<o:p></o:p></span></p>
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