Browse Source

Add release notes for 1.9.19 (Java 19)

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>
tags/V1_9_19
Alexander Kriegisch 1 year ago
parent
commit
b781362e74
2 changed files with 165 additions and 0 deletions
  1. 163
    0
      docs/dist/doc/README-1919.html
  2. 2
    0
      docs/dist/doc/index.html

+ 163
- 0
docs/dist/doc/README-1919.html View File

@@ -0,0 +1,163 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<html>

<head>
<title>AspectJ 1.9.19 Readme</title>
<style type="text/css">
<!--
P { margin-left: 20px; }
PRE { margin-left: 20px; }
LI { margin-left: 20px; }
H4 { margin-left: 20px; }
H3 { margin-left: 10px; }
-->
</style>
</head>

<body>
<div align="right"><small>&copy; Copyright 2022 Contributors. All rights reserved.</small></div>

<h1>AspectJ 1.9.19</h1>

<p>
Please note that Bugzilla for issue management is deprecated and new issues should be filed as
<a href="https://github.com/eclipse/org.aspectj/issues/new">GitHub issues</a>.
The list of issues addressed for 1.9.19 can be found here:
<ul>
<li><a href="https://github.com/eclipse/org.aspectj/issues?q=is%3Aissue+is%3Aclosed++milestone%3A1.9.19">GitHub 1.9.19</a></li>
<li><a href="https://bugs.eclipse.org/bugs/buglist.cgi?bug_status=RESOLVED&bug_status=VERIFIED&bug_status=CLOSED&f0=OP&f1=OP&f3=CP&f4=CP&j1=OR&list_id=16866879&product=AspectJ&query_format=advanced&target_milestone=1.9.19">Bugzilla 1.9.19</a></li>
</ul>
</p>

<h2>New features</h2>

<p>
AspectJ 1.9.19 supports <a href="https://openjdk.java.net/projects/jdk/19/">Java 19</a> and its final, preview and
incubator features, such as:
</p>
<ul>
<li>Record patterns (preview)</li>
<li>Virtual threads (preview)</li>
<li>Pattern matching for <tt>switch</tt> (preview 3)</li>
<li>Structured concurrency (incubator)</li>
</ul>

Please note that the upstream Eclipse Java Compiler (ECJ) which the AspectJ Compiler (AJC) is a fork of still has some
open issues concerning Java 19 preview feature support, see the list in
<a href="https://github.com/eclipse/org.aspectj/issues/184#issuecomment-1272254940">this comment</a>. AJC therefore
inherits the same problems for the specific cases described in the linked issues.

<h2>Improvements</h2>

<p>
In annotation style aspects, asynchronous <tt>proceed()</tt> calls in <tt>@Around</tt> advice now works in threads
created from within the advice. Previously, this was only working in native syntax aspects. There is still a
limitation with regard to asynchronous proceed, if you do not create the thread in the advice but want to use e.g.
an <tt>ExecutorService</tt> with its own thread pool. This still is not working in annotation style aspects, only in
native syntax ones.
</p>
<p>
See <a href="https://github.com/eclipse/org.aspectj/issues/128">issue #128</a> and
<a href="https://github.com/eclipse/org.aspectj/pull/132">pull request #132</a> for more details.
</p>
<h2>Code examples</h2>

<p>
You can find some sample code in the AspectJ test suite under the respective AspectJ version in which the features
were first supported (possibly as JVM preview features):
</p>
<ul>
<li>
<a href="https://github.com/eclipse/org.aspectj/tree/master/tests/features198/java17">
Pattern matching for switch (preview 1)
</a>
</li>
<li>
<a href="https://github.com/eclipse/org.aspectj/tree/master/tests/features199/java18">
Pattern matching for switch (preview 2)
</a>
</li>
<li>
<a href="https://github.com/eclipse/org.aspectj/tree/master/tests/features199/java18">
Pattern matching for switch (preview 3), record patterns (preview 1)
</a>
</li>
<li>
<a href="https://github.com/eclipse/org.aspectj/tree/master/tests/bugs199/github_128">
Asynchronous proceed in native vs. annotation style syntax
</a>
</li>
<li>
Please note that presently there is no specific sample code for virtual threads and structured concurrency in the
AspectJ code base, because these are just new APIs, no Java language features. You can find sample code for these
concurrency features elsewhere, e.g. in the corresponding JEPs. In AspectJ, they should just work transparently
like any other Java API.
</li>
</ul>

<h2>Other changes and bug fixes</h2>

<ul>
<li>
Fix a bug which led to <tt>NullPointerException</tt>s if too many JAR archives were on the classpath. Too many here
means the value system property <tt>org.aspectj.weaver.openarchives</tt> (1,000 by default). The AspectJ compiler is
meant to close archives upon cache exhaustion and then re-open them if it needs them again later. Re-opening was
broken, now the compiler works reliably even for cache sizes as small as 20. See issue
<a href="https://github.com/eclipse/org.aspectj/issues/125">#125</a>.
</li>
<li>
Improvements for <tt>if()</tt> pointcuts in annotation syntax, see issues
<a href="https://github.com/eclipse/org.aspectj/issues/115">#115</a>,
<a href="https://github.com/eclipse/org.aspectj/issues/120">#120</a>,
<a href="https://github.com/eclipse/org.aspectj/issues/122">#122</a>.
</li>
<li>
Thanks to Andrey Turbanov for several clean code contributions.
</li>
</ul>

<h2>AspectJ usage hints</h2>

<h3>AspectJ compiler build system requirements</h3>

<p>
Since 1.9.7, the AspectJ compiler <tt>ajc</tt> (contained in the <tt>aspectjtools</tt> library) no longer works on
JDKs 8 to 10. The minimum compile-time requirement is now JDK 11 due to upstream changes in the Eclipse Java Compiler
(subset of JDT Core), which AspectJ is a fork of. You can still compile to legacy target versions as low as Java 1.3
when compiling plain Java code or using plain Java ITD constructs which do not require the AspectJ runtime
<tt>aspectjrt</tt>, but the compiler itself needs JDK 11+. Just like in previous AspectJ versions, both the runtime
<tt>aspectjrt</tt> and the load-time weaver <tt>aspectjweaver</tt> still only require JRE 8+.
</p>

<h3>Use LTW on Java 16+</h3>

<p>
Please note that if you want to use load-time weaving on Java 16+, the weaving agent collides with
<a href="https://openjdk.java.net/jeps/396">JEP 396 (Strongly Encapsulate JDK Internals by Default)</a> and related
subsequent JEPs. Therefore, you need to set the JVM parameter <tt>--add-opens java.base/java.lang=ALL-UNNAMED</tt> in
order to enable aspect weaving. This is due to the fact that the weaver uses internal APIs for which we have not found
an adequate replacement yet when defining classes in different classloaders.
</p>

<h3>Compile with Java preview features</h3>

<p>
For features marked as preview on a given JDK, you need to compile with <tt>ajc --enable-preview</tt> and run with
<tt>java --enable-preview</tt> on that JDK.
</p>
<p>
Please note that you cannot run code compiled with preview features on any other JDK than the one used for
compilation. For example, records compiled with preview on JDK 15 cannot be used on JDK 16 without recompilation. This
is a JVM limitation unrelated to AspectJ. Also, e.g. sealed classes are preview-1 on JDK 15 and preview-2 on JDK 16.
You still need to recompile, no matter what.
</p>

<hr>

<p>
<b>Available:</b> 1.9.19 on DD-MMM-2022
</p>

</body>

</html>

+ 2
- 0
docs/dist/doc/index.html View File

@@ -136,6 +136,8 @@
<tr> <td>README's
</td>
<td>Changes and porting guide for AspectJ
<a href="README-1919.html">1.9.19</a>,
<a href="README-199.html">1.9.9 and 1.9.9.1</a>,
<a href="README-198.html">1.9.8</a>,
<a href="README-197.html">1.9.7</a>,
<a href="README-196.html">1.9.6</a>,

Loading…
Cancel
Save