Log4j 2.x doesn’t “support” Java 17. It tolerates it. There is a big difference.
Ralph > On May 16, 2022, at 1:26 PM, Volkan Yazıcı <vol...@yazi.ci> wrote: > > I don't understand. There are many Java 17 users using Log4j 2. Why can't > they simply switch to Java 19, take advantage of its concurrency benefits, > and still expect their logs to work? > > On Mon, May 16, 2022 at 10:05 PM Matt Sicker <boa...@gmail.com> wrote: > >> Because this is a feature that's only in preview mode as of Java 19, >> so finding a way to support this for Java 8 users is a waste of time. >> >> On Mon, May 16, 2022 at 1:59 PM Volkan Yazıcı <vol...@yazi.ci> wrote: >>> >>> Definitely support the idea of investigation whether it impacts >>> ThreadContext usage or not. I suspect certain thread-local usages might >> be >>> broken too. >>> >>> Why do you think this should be targeted for the master branch only? >>> >>> On Mon, May 16, 2022 at 8:37 PM Ralph Goers <ralph.go...@dslextreme.com> >>> wrote: >>> >>>> Removing David, >>>> >>>> We are going to have to investigate this and determine how it impacts >>>> ThreadContext usage. Note that this should be targeted for the master >>>> branch only. >>>> >>>> Ralph >>>> >>>> >>>>> On May 16, 2022, at 12:50 AM, David Delabassee < >>>> david.delabas...@oracle.com> wrote: >>>>> >>>>> Welcome to a new Quality Outreach update! >>>>> >>>>> This time, we have one update but a major one: JEP 425 (Virtual >> Threads >>>> preview) has been integrated into the OpenJDK mainline! JDK 19 >> Early-Access >>>> builds 22 are the first mainline builds with Virtual Threads (preview) >>>> support. So, Project Loom is now getting closer and closer! >>>>> >>>>> Please make sure to check the Heads-up below even if you don’t >> intend to >>>> use virtual threads in the short future. >>>>> >>>>> >>>>> ## Heads-up - JEP 425 Virtual Threads (preview) testing >>>>> >>>>> The goal of Project Loom is to introduce in the Java platform an >>>> easy-to-use, high-throughput lightweight concurrency model, and a >> related >>>> new concurrent programming model. >>>>> >>>>> Developed in Project Loom, JEP 425 introduces virtual threads to the >>>> Java Platform. Virtual threads are lightweight threads that >> dramatically >>>> reduce the effort of writing, maintaining, and observing >> high-throughput >>>> concurrent applications. Note that virtual threads are a preview API >> in JDK >>>> 19. Please make sure to read 'JEP 425: Virtual Threads (Preview)' for a >>>> detailed explanation. >>>>> >>>>> A lot of testing has already been done but we are asking, once again, >>>> your help to test your project(s) with the latest JDK 19 Early-Access >>>> builds, even if you don’t intend to use virtual threads any time soon. >>>>> >>>>> There are two approaches to test your project: >>>>> 1. Update your code to use virtual threads …or >>>>> 2. Simply test your existing unchanged code with the preview feature >>>> enabled. >>>>> >>>>> Both approaches should yield valuable feedback. >>>>> >>>>> If you choose to adapt your application to use virtual threads (cf. >>>> JavaDoc [2]), be aware that in some cases it’s not just about updating >> your >>>> code to use virtual threads instead of platform threads; there are some >>>> additional considerations. For example, virtual threads shouldn’t be >> pooled >>>> [3], code that relies heavily on thread locals [4] will require some >> work >>>> to move to a world where there is a new thread for each task, etc. >>>>> >>>>> Given that are some minor behavior changes and that `ThreadGroup` has >>>> been degraded, testing your code as-is, i.e., without using virtual >> threads >>>> but with the preview feature enabled at runtime, will also be useful. >> For >>>> more details, please check 'JEP 425 - Risks and Assumptions' [5]. >>>>> >>>>> One difference between to the EA builds published by Project Loom and >>>> the latest JDK 19 EA builds is that the `--enable-preview` flag is >> required >>>> at run-time to use the new APIs. It’s not possible to use the APIs with >>>> core reflection to avoid the need for `--enable-preview`. >>>>> >>>>> Finally, some tools especially tools relying on JVM TI agents might >> not >>>> be fully ready for virtual threads. >>>>> >>>>> Your help testing this important update is greatly appreciated, all >>>> feedback should be sent to the 'loom-dev' mailing list [6]. >>>>> >>>>> [1] https://openjdk.java.net/jeps/425 >>>>> [2] >>>> >> https://download.java.net/java/early_access/jdk19/docs/api/java.base/java/lang/Thread.html >>>>> [3] https://openjdk.java.net/jeps/425#Do-not-pool-virtual-threads >>>>> [4] https://openjdk.java.net/jeps/425#Thread-local-variables >>>>> [5] https://openjdk.java.net/jeps/425#Risks-and-Assumptions >>>>> [6] https://mail.openjdk.java.net/pipermail/loom-dev/ >>>>> >>>>> >>>>> ## JDK 19 Early-Access builds >>>>> >>>>> JDK 19 Early-Access builds 22 are now available [7], and are provided >>>> under the GNU General Public License v2, with the Classpath Exception. >> Make >>>> sure to check the Release Notes [8] and the JavaDoc [9]. >>>>> >>>>> [7] https://jdk.java.net/19/ >>>>> [8] https://jdk.java.net/19/release-notes >>>>> [9] https://download.java.net/java/early_access/jdk19/docs/ >>>>> >>>>> ### Current JDK 19 JEPs >>>>> - 405: Record Patterns (Preview) - Proposed to target >>>>> - 422: Linux/RISC-V Port - Integrated >>>>> - 424: Foreign Function & Memory API (Preview) - Integrated >>>>> - 425: Virtual Threads (Preview) - Integrated >>>>> - 426: Vector API (4th Incubator) - Targeted >>>>> - 427: Pattern Matching for switch (3rd Preview) - Targeted >>>>> >>>>> ### Recent changes that may be of interest: >>>>> >>>>> Build 22: >>>>> - JDK-8284161: Implementation of Virtual Threads (Preview) >>>>> - JDK-8285947: Avoid redundant HashMap.containsKey calls in ZoneName >>>>> - JDK-8212136: Remove finalizer implementation in SSLSocketImpl >>>>> - JDK-8285872: JFR: Remove finalize() methods >>>>> - JDK-8285914: AppCDS crash when using shared archive with old class >> file >>>>> - JDK-8286163: micro-optimize Instant.plusSeconds >>>>> - JDK-8282420: JFR: Remove event handlers >>>>> - JDK-8282559: Allow multiple search terms in javadoc search >>>>> >>>>> Build 21: >>>>> - JDK-8255552: Add DES/3DES/MD5 to jdk.security.legacyAlgorithms >>>>> - JDK-8278370: [win] Disable side-by-side installations of multiple >> JDK >>>> updates in Windows JDK installers >>>>> - JDK-8281010: [macos] Disable side-by-side installations of multiple >>>> JDK updates in macOS JDK installers >>>>> - JDK-8236128: Allow jpackage create installers for services >>>>> - JDK-8279598: provide adapter from RandomGenerator to Random >>>>> >>>>> Build 20: >>>>> - JDK-8284553: Deprecate the DEFAULT static field of >> OAEPParameterSpec >>>>> - JDK-8283620: System.out does not use the encoding/charset >> specified in >>>> the Javadoc >>>>> - JDK-8285445: Enable Windows Alternate Data Streams by default >>>>> - JDK-8284930: Re-examine FilterInputStream mark/reset >>>>> - JDK-8284890: Support for Do not fragment IP socket options >>>>> - JDK-8282823: javac should constrain more uses of preview APIs >>>>> - JDK-8285477: Add a PRECISION public static field to j.l.Float and >>>> j.l.Double >>>>> >>>>> Build 19: >>>>> - JDK-8186958: New Methods to Create Preallocated HashMaps >>>>> - JDK-8284775: Simplify String.substring(_, length()) calls >>>>> - JDK-8283892: Compress and expand bits >>>>> - JDK-8280915: Better parallelization for AbstractSpliterator and >>>> IteratorS… >>>>> - JDK-8284681: compiler/c2/aarch64/TestFarJump.java fails with >>>> "RuntimeExce… >>>>> - JDK-8283790: G1: Remove redundant card/heap-address transition >>>>> - JDK-8285001: Simplify StringLatin1.regionMatches >>>>> - JDK-8284880: Re-examine sun.invoke.util.Wrapper hash tables >>>>> - JDK-8278356: Improve file creation >>>>> >>>>> >>>>> ## Topics of Interest >>>>> >>>>> - Java Cryptographic Roadmap update >>>> https://java.com/en/jre-jdk-cryptoroadmap.html >>>>> - Virtual Thread Deep Dive >>>> https://inside.java/2022/04/07/insidejava-newscast-023/ >>>>> - Why Write an Empty finalize() Method? >>>> >> https://stuartmarks.wordpress.com/2022/04/27/why-write-an-empty-finalize-method/ >>>>> - WHEN and NULL In Pattern Matching >>>> https://inside.java/2022/05/05/insidejava-newscast-024/ >>>>> - JDK 8 to JDK 18 in GC: 10 Releases, 2000+ Enhancements >>>> https://inside.java/2022/05/02/odl-jdk8-to-jdk18-gc/ >>>>> - ZGC - What's new in JDK 18 https://malloc.se/blog/zgc-jdk18 >>>>> - Java Next - From Amber to Loom, from Panama to Valhalla >>>> https://inside.java/2022/05/09/java-next/ >>>>> >>>>> >>>>> ## JDK Update Patch Release >>>>> >>>>> As announced with the April 2022 CPU release, we have produced update >>>> patch releases for all Java SE supported versions. The new versions >> are JDK >>>> 18.0.1.1 (publicly available), 17.0.3.1 (publicly available), >> 11.0.15.1, >>>> 8u333, 7u343, and OpenJDK 18.0.1.1 (publicly available). >>>>> >>>>> >>>>> As usual, let us know if you find any issues while testing your >>>> project(s) on the latest JDK early-access builds. Thanks for your >> support! >>>>> >>>>> --David >>>>> >>>>> >>>>> >>>>> >>>> >>>> >>
