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<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Arial",sans-serif;color:#1F497D">Hi,
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Arial",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Arial",sans-serif;color:#1F497D">regarding (3), the link just says Charset, not StandardCharset. Please clarify.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Arial",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Arial",sans-serif;color:#1F497D">Jonathan<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Arial",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ligatures:none">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-ligatures:none"> panama-dev <panama-dev-retn@openjdk.org>
<b>On Behalf Of </b>Maurizio Cimadamore<br>
<b>Sent:</b> Monday, June 10, 2024 12:46 PM<br>
<b>To:</b> Cheng Jin <jincheng@ca.ibm.com>; panama-dev@openjdk.org<br>
<b>Subject:</b> Re: As for the refinements mentioned in JEP454<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p>Hi, some answers below:<span style="font-size:11.0pt;mso-ligatures:none"><o:p></o:p></span></p>
<p>(1) refers to the ability to query what primitive layouts are like, using Linker::canonicalLayouts.<br>
See: <a 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><o:p></o:p></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 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 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><o:p></o:p></p>
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<p class="MsoNormal">Maurizio<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On 07/06/2024 23:30, Cheng Jin wrote:<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Hi there, </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></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">https://openjdk.org/jeps/454</a> in which some of refinements confused me as follows:</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<ol style="margin-top:0in" start="1" type="1">
<li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo3"><i><span style="font-size:11.0pt">Enabled clients to build C-language function descriptors programmatically, avoiding platform-specific constants;</span></i><o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo3"><i><span style="font-size:11.0pt">Improved support for variable-length arrays in native memory;</span></i><o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo3"><i><span style="font-size:11.0pt">Added support for arbitrary charsets for native strings.</span></i><o:p></o:p></li></ol>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></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.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Could anybody explain these refinements in more details? Many thanks.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Best Regards</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Cheng</span><o:p></o:p></p>
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