January 2021 - core-libs-dev

RFR: 8258422: Cleanup unnecessary null comparison before instanceof check in java.base
by Andrey Turbanov 11 Jan '21

11 Jan '21

8258422: Cleanup unnecessary null comparison before instanceof check in java.base ------------- Commit messages: - [PATCH] Cleanup unnecessary null comparison before instanceof check in java.base Changes: https://git.openjdk.java.net/jdk/pull/20/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=20&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8258422 Stats: 42 lines in 21 files changed: 0 ins; 0 del; 42 mod Patch: https://git.openjdk.java.net/jdk/pull/20.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/20/head:pull/20 PR: https://git.openjdk.java.net/jdk/pull/20

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RFR: 8259528: Broken Link for [java.text.Normalizer.Form]
by Naoto Sato 11 Jan '21

11 Jan '21

Please review this simple doc fix. ------------- Commit messages: - 8259528: Broken Link for [java.text.Normalizer.Form] Changes: https://git.openjdk.java.net/jdk/pull/2028/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2028&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8259528 Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod Patch: https://git.openjdk.java.net/jdk/pull/2028.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2028/head:pull/2028 PR: https://git.openjdk.java.net/jdk/pull/2028

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[jdk16] RFR: 8259028: ClassCastException when using custom filesystem with wrapper FileChannel impl
by Maurizio Cimadamore 11 Jan '21

11 Jan '21

This patch tweaks `MemorySegment::mapFile` so that it will throw `IllegalArgumentException` whenever the path to be mapped is associated with a custom file system provider. The check in the implementation is heavily borrowed by what `UnixDomainSocketAddress::of(Path)` does (thanks Alan for the tip!). Not only we have to check if file system is the default one, but also if the default FS belongs to java.base (since that can be overridden). The test simply check that paths coming from the (internal) JRT file system are not supported by the factory. ------------- Commit messages: - Tweak javadoc - Clarify javadoc of MemorySegment::mapFile w.r.t. custom file systems Changes: https://git.openjdk.java.net/jdk16/pull/90/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk16&pr=90&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8259028 Stats: 22 lines in 3 files changed: 16 ins; 1 del; 5 mod Patch: https://git.openjdk.java.net/jdk16/pull/90.diff Fetch: git fetch https://git.openjdk.java.net/jdk16 pull/90/head:pull/90 PR: https://git.openjdk.java.net/jdk16/pull/90

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RFR: 8228988: AnnotationParser throws NullPointerException on incompatible member type
by Rafael Winterhalter 11 Jan '21

11 Jan '21

If an annotation member type is changed in an incompatible manner, the `AnnotationParser` currently throws a `NullPointerException` if: - An enumeration-typed member is changed to be an annotation type or a `Class` type. - An annotation type is changed to be a non-annotation type. This patch creates `AnnotationTypeMismatchExceptionProxy` to give users a better error message and to delay the exception to the time where the annotation member is attempted to be accessed. ------------- Commit messages: - 8228988: AnnotationParser throws NullPointerException on incompatible member type Changes: https://git.openjdk.java.net/jdk/pull/725/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=725&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8228988 Stats: 10 lines in 1 file changed: 6 ins; 0 del; 4 mod Patch: https://git.openjdk.java.net/jdk/pull/725.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/725/head:pull/725 PR: https://git.openjdk.java.net/jdk/pull/725

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RFR: JDK-8250768: javac should be adapted to changes in JEP 12
by Jan Lahoda 11 Jan '21

11 Jan '21

This is an update to javac and javadoc, to introduce support for Preview APIs, and generally improve javac and javadoc behavior to more closely adhere to JEP 12. The notable changes are: * adding support for Preview APIs (javac until now supported primarily only preview language features, and APIs associated with preview language features). This includes: * the @PreviewFeature annotation has boolean attribute "reflective", which should be true for reflective Preview APIs, false otherwise. This replaces the existing "essentialAPI" attribute with roughly inverted meaning. * the preview warnings for preview APIs are auto-suppressed as described in the JEP 12. E.g. the module that declares the preview API is free to use it without warnings * improving error/warning messages. Please see [1] for a list of cases/examples. * class files are only marked as preview if they are using a preview feature. [1] also shows if a class file is marked as preview or not. * the PreviewFeature annotation has been moved to jdk.internal.javac package (originally was in the jdk.internal package). * Preview API in JDK's javadoc no longer needs to specify @preview tag in the source files. javadoc will auto-generate a note for @PreviewFeature elements, see e.g. [2] and [3] (non-reflective and reflective API, respectively). A summary of preview elements is also provided [4]. Existing uses of @preview have been updated/removed. * non-JDK javadoc is also enhanced to auto-generate preview notes for uses of Preview elements, and for declaring elements using preview language features [5]. Please also see the CSR [6] for more information. [1] http://cr.openjdk.java.net/~jlahoda/8250768/JEP12-errors-warnings-v6.html [2] http://cr.openjdk.java.net/~jlahoda/8250768/jdk.javadoc.00/api/java.base/ja… [3] http://cr.openjdk.java.net/~jlahoda/8250768/jdk.javadoc.00/api/java.compile… [4] http://cr.openjdk.java.net/~jlahoda/8250768/jdk.javadoc.00/api/preview-list… [5] http://cr.openjdk.java.net/~jlahoda/8250768/test.javadoc.00/ [6] https://bugs.openjdk.java.net/browse/JDK-8250769 ------------- Commit messages: - Fixing tests. - Various cleanup. - The Preview taglet is not needed anymore. - There is not jdk.internal package anymore - No, jdk.incubator.vector does not need jdk.internal package. - Merging master into JDK-8250768 - Fixing tests. - Adding forgotten files. - Updating build. - Post-merge fix. - ... and 19 more: https://git.openjdk.java.net/jdk/compare/9359ff03...efb37a9b Changes: https://git.openjdk.java.net/jdk/pull/703/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=703&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8250768 Stats: 3179 lines in 158 files changed: 2487 ins; 410 del; 282 mod Patch: https://git.openjdk.java.net/jdk/pull/703.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/703/head:pull/703 PR: https://git.openjdk.java.net/jdk/pull/703

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RFR: 8253280: Use class name as class loading lock
by Robert LU 11 Jan '21

11 Jan '21

When many thread try to load same class, the thread will stuck on `ClassLoader.loadClass`. At current jdk, the stacktrace by example program is: "Thread-1" prio=5 Id=13 BLOCKED on java.lang.String@724af044 owned by "Thread-0" Id=12 at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:646) - blocked on java.lang.String@724af044 val="java.lang.String" at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:634) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:182) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:519) at app//Main2.test(Main2.java:19) at app//Main2$$Lambda$37/0x00000001000c2a20.run(Unknown Source) at java.base/java.lang.Thread.run(Thread.java:831) There is no way to get which class stuck the thread. **After this patch, the stacktrace will be**: "Thread-2" prio=5 Id=13 BLOCKED on java.lang.String@724af044 owned by "Thread-3" Id=14 at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:612) - blocked on java.lang.String@724af044 val="java.lang.String" at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:600) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522) at app//Main2.test(Main2.java:18) at app//Main2$$Lambda$38/0x0000000100097440.run(Unknown Source) at java.base/java.lang.Thread.run(Thread.java:832) That is, user will know which class stuck the thread, in this example, the class is `java.lang.String`. It's helpful for troubleshooting. The example program: Before patch: <details> <summary>Main.java</summary> // Main.java import java.io.PrintStream; import java.lang.management.*; public final class Main { private synchronized static void test1() { while (true) { try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } } } private static void test() { while (true) { try { Main.class.getClassLoader().loadClass("java.lang.String"); } catch (ClassNotFoundException e) { } } } public static void main(String[] args) throws InterruptedException, NoSuchFieldException, IllegalAccessException { new Thread(Main::test).start(); new Thread(Main::test).start(); new Thread(Main::test).start(); new Thread(Main::test).start(); new Thread(Main::test).start(); while (true) { Thread.sleep(1000); ThreadMXBean bean = ManagementFactory.getThreadMXBean(); ThreadInfo[] infos = bean.dumpAllThreads(true, true); for (ThreadInfo info : infos) { System.out.println(printThreadInfo(info)); } } } private static String printThreadInfo(ThreadInfo threadInfo) { StringBuilder sb = new StringBuilder(""" + threadInfo.getThreadName() + """ + (threadInfo.isDaemon() ? " daemon" : "") + " prio=" + threadInfo.getPriority() + " Id=" + threadInfo.getThreadId() + " " + threadInfo.getThreadState()); if (threadInfo.getLockName() != null) { sb.append(" on " + threadInfo.getLockName()); } if (threadInfo.getLockOwnerName() != null) { sb.append(" owned by "" + threadInfo.getLockOwnerName() + "" Id=" + threadInfo.getLockOwnerId()); } if (threadInfo.isSuspended()) { sb.append(" (suspended)"); } if (threadInfo.isInNative()) { sb.append(" (in native)"); } sb.append('\n'); int i = 0; StackTraceElement[] stackTrace = threadInfo.getStackTrace(); for (; i < stackTrace.length; i++) { StackTraceElement ste = stackTrace[i]; sb.append("\tat " + ste.toString()); sb.append('\n'); if (i == 0 && threadInfo.getLockInfo() != null) { Thread.State ts = threadInfo.getThreadState(); switch (ts) { case BLOCKED: sb.append("\t- blocked on " + printLockInfo(threadInfo.getLockInfo())); sb.append('\n'); break; case WAITING: sb.append("\t- waiting on " + printLockInfo(threadInfo.getLockInfo())); sb.append('\n'); break; case TIMED_WAITING: sb.append("\t- waiting on " + printLockInfo(threadInfo.getLockInfo())); sb.append('\n'); break; default: } } for (MonitorInfo mi : threadInfo.getLockedMonitors()) { if (mi.getLockedStackDepth() == i) { sb.append("\t- locked " + printLockInfo(mi)); sb.append('\n'); } } } if (i < stackTrace.length) { sb.append("\t..."); sb.append('\n'); } LockInfo[] locks = threadInfo.getLockedSynchronizers(); if (locks.length > 0) { sb.append("\n\tNumber of locked synchronizers = " + locks.length); sb.append('\n'); for (LockInfo li : locks) { sb.append("\t- " + printLockInfo(li)); sb.append('\n'); } } sb.append('\n'); return sb.toString(); } private static String printLockInfo(LockInfo li) { String res = li.getClassName() + '@' + Integer.toHexString(li.getIdentityHashCode()); return res; } } </details> After patch: <details> <summary>Main2.java</summary> // Main2.java import java.io.PrintStream; import java.lang.management.*; public final class Main2 { private synchronized static void test1() { while (true) { try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } } } private static void test() { while (true) { try { Main2.class.getClassLoader().loadClass("java.lang.String"); } catch (ClassNotFoundException e) { } } } public static void main(String[] args) throws InterruptedException, NoSuchFieldException, IllegalAccessException { new Thread(Main2::test).start(); new Thread(Main2::test).start(); new Thread(Main2::test).start(); new Thread(Main2::test).start(); new Thread(Main2::test).start(); while (true) { Thread.sleep(1000); ThreadMXBean bean = ManagementFactory.getThreadMXBean(); ThreadInfo[] infos = bean.dumpAllThreads(true, true); for (ThreadInfo info : infos) { System.out.println(printThreadInfo(info)); } } } private static String printThreadInfo(ThreadInfo threadInfo) { StringBuilder sb = new StringBuilder(""" + threadInfo.getThreadName() + """ + (threadInfo.isDaemon() ? " daemon" : "") + " prio=" + threadInfo.getPriority() + " Id=" + threadInfo.getThreadId() + " " + threadInfo.getThreadState()); if (threadInfo.getLockName() != null) { sb.append(" on " + threadInfo.getLockName()); } if (threadInfo.getLockOwnerName() != null) { sb.append(" owned by "" + threadInfo.getLockOwnerName() + "" Id=" + threadInfo.getLockOwnerId()); } if (threadInfo.isSuspended()) { sb.append(" (suspended)"); } if (threadInfo.isInNative()) { sb.append(" (in native)"); } sb.append('\n'); int i = 0; StackTraceElement[] stackTrace = threadInfo.getStackTrace(); for (; i < stackTrace.length; i++) { StackTraceElement ste = stackTrace[i]; sb.append("\tat " + ste.toString()); sb.append('\n'); if (i == 0 && threadInfo.getLockInfo() != null) { Thread.State ts = threadInfo.getThreadState(); switch (ts) { case BLOCKED: sb.append("\t- blocked on " + printLockInfo(threadInfo.getLockInfo())); sb.append('\n'); break; case WAITING: sb.append("\t- waiting on " + printLockInfo(threadInfo.getLockInfo())); sb.append('\n'); break; case TIMED_WAITING: sb.append("\t- waiting on " + printLockInfo(threadInfo.getLockInfo())); sb.append('\n'); break; default: } } for (MonitorInfo mi : threadInfo.getLockedMonitors()) { if (mi.getLockedStackDepth() == i) { sb.append("\t- locked " + printLockInfo(mi)); sb.append('\n'); } } } if (i < stackTrace.length) { sb.append("\t..."); sb.append('\n'); } LockInfo[] locks = threadInfo.getLockedSynchronizers(); if (locks.length > 0) { sb.append("\n\tNumber of locked synchronizers = " + locks.length); sb.append('\n'); for (LockInfo li : locks) { sb.append("\t- " + printLockInfo(li)); sb.append('\n'); } } sb.append('\n'); return sb.toString(); } private static String printLockInfo(LockInfo li) { String res = li.getClassName() + '@' + Integer.toHexString(li.getIdentityHashCode()); // There is no getLock method in current jdk if (li.getStringValue() != null) { return res + " val="" + li.getStringValue() + """; } return res; } } </details> ------------- Commit messages: - 8253280: Use class name as class loading lock Changes: https://git.openjdk.java.net/jdk/pull/104/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=104&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8253280 Stats: 73 lines in 5 files changed: 72 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/104.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/104/head:pull/104 PR: https://git.openjdk.java.net/jdk/pull/104

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Withdrawn: JDK-8189198: Add "forRemoval = true" to Applet APIs
by Andy Herrick 11 Jan '21

11 Jan '21

On Mon, 9 Nov 2020 13:56:33 GMT, Andy Herrick <herrick(a)openjdk.org> wrote: > JDK-8189198: Add "forRemoval = true" to Applet APIs This pull request has been closed without being integrated. ------------- PR: https://git.openjdk.java.net/jdk/pull/1127

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RFR: 8254973: CompletableFuture.ThreadPerTaskExecutor does not throw NPE in #execute
by Martin Buchholz 10 Jan '21

10 Jan '21

8254973: CompletableFuture.ThreadPerTaskExecutor does not throw NPE in #execute ------------- Commit messages: - JDK-8254973 Changes: https://git.openjdk.java.net/jdk/pull/2018/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2018&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8254973 Stats: 5 lines in 1 file changed: 4 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/2018.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2018/head:pull/2018 PR: https://git.openjdk.java.net/jdk/pull/2018

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RFR: 8259518: Fixes for rare test failures due to 8246585: ForkJoin updates
by Martin Buchholz 10 Jan '21

10 Jan '21

8259518: Fixes for rare test failures due to 8246585: ForkJoin updates ------------- Commit messages: - JDK-8259518 Changes: https://git.openjdk.java.net/jdk/pull/2015/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2015&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8259518 Stats: 30 lines in 2 files changed: 22 ins; 0 del; 8 mod Patch: https://git.openjdk.java.net/jdk/pull/2015.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2015/head:pull/2015 PR: https://git.openjdk.java.net/jdk/pull/2015

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RFR: 8258217: PriorityBlockingQueue constructor spec and behavior mismatch
by Martin Buchholz 10 Jan '21

10 Jan '21

8258217: PriorityBlockingQueue constructor spec and behavior mismatch ------------- Commit messages: - JDK-8258217 Changes: https://git.openjdk.java.net/jdk/pull/2014/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2014&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8258217 Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/2014.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2014/head:pull/2014 PR: https://git.openjdk.java.net/jdk/pull/2014

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