diff --git a/src/java.base/share/classes/java/lang/ref/Reference.java b/src/java.base/share/classes/java/lang/ref/Reference.java index ef2e5e0d0c4f5..7d48b394f89b2 100644 --- a/src/java.base/share/classes/java/lang/ref/Reference.java +++ b/src/java.base/share/classes/java/lang/ref/Reference.java @@ -25,12 +25,10 @@ package java.lang.ref; -import jdk.internal.misc.Unsafe; import jdk.internal.vm.annotation.ForceInline; import jdk.internal.vm.annotation.IntrinsicCandidate; import jdk.internal.access.JavaLangRefAccess; import jdk.internal.access.SharedSecrets; -import jdk.internal.ref.Cleaner; /** * Abstract base class for reference objects. This class defines the @@ -199,11 +197,6 @@ private static class ReferenceHandler extends Thread { } public void run() { - // pre-load and initialize Cleaner class so that we don't - // get into trouble later in the run loop if there's - // memory shortage while loading/initializing it lazily. - Unsafe.getUnsafe().ensureClassInitialized(Cleaner.class); - while (true) { processPendingReferences(); } @@ -253,18 +246,7 @@ private static void processPendingReferences() { Reference ref = pendingList; pendingList = ref.discovered; ref.discovered = null; - - if (ref instanceof Cleaner) { - ((Cleaner)ref).clean(); - // Notify any waiters that progress has been made. - // This improves latency for nio.Bits waiters, which - // are the only important ones. - synchronized (processPendingLock) { - processPendingLock.notifyAll(); - } - } else { - ref.enqueueFromPending(); - } + ref.enqueueFromPending(); } // Notify any waiters of completion of current round. synchronized (processPendingLock) { diff --git a/src/java.base/share/classes/jdk/internal/ref/Cleaner.java b/src/java.base/share/classes/jdk/internal/ref/Cleaner.java deleted file mode 100644 index ecd1c32167ffa..0000000000000 --- a/src/java.base/share/classes/jdk/internal/ref/Cleaner.java +++ /dev/null @@ -1,150 +0,0 @@ -/* - * Copyright (c) 2003, 2024, Oracle and/or its affiliates. All rights reserved. - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This code is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 only, as - * published by the Free Software Foundation. Oracle designates this - * particular file as subject to the "Classpath" exception as provided - * by Oracle in the LICENSE file that accompanied this code. - * - * This code is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * version 2 for more details (a copy is included in the LICENSE file that - * accompanied this code). - * - * You should have received a copy of the GNU General Public License version - * 2 along with this work; if not, write to the Free Software Foundation, - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA - * or visit www.oracle.com if you need additional information or have any - * questions. - */ - -package jdk.internal.ref; - -import java.lang.ref.*; - - -/** - * General-purpose phantom-reference-based cleaners. - * - *

Cleaners are a lightweight and more robust alternative to finalization. - * They are lightweight because they are not created by the VM and thus do not - * require a JNI upcall to be created, and because their cleanup code is - * invoked directly by the reference-handler thread rather than by the - * finalizer thread. They are more robust because they use phantom references, - * the weakest type of reference object, thereby avoiding the nasty ordering - * problems inherent to finalization. - * - *

A cleaner tracks a referent object and encapsulates a thunk of arbitrary - * cleanup code. Some time after the GC detects that a cleaner's referent has - * become phantom-reachable, the reference-handler thread will run the cleaner. - * Cleaners may also be invoked directly; they are thread safe and ensure that - * they run their thunks at most once. - * - *

Cleaners are not a replacement for finalization. They should be used - * only when the cleanup code is extremely simple and straightforward. - * Nontrivial cleaners are inadvisable since they risk blocking the - * reference-handler thread and delaying further cleanup and finalization. - * - * - * @author Mark Reinhold - */ - -public class Cleaner - extends PhantomReference -{ - - // Dummy reference queue, needed because the PhantomReference constructor - // insists that we pass a queue. Nothing will ever be placed on this queue - // since the reference handler invokes cleaners explicitly. - // - private static final ReferenceQueue dummyQueue = new ReferenceQueue<>(); - - // Doubly-linked list of live cleaners, which prevents the cleaners - // themselves from being GC'd before their referents - // - private static Cleaner first = null; - - private Cleaner - next = null, - prev = null; - - private static synchronized Cleaner add(Cleaner cl) { - if (first != null) { - cl.next = first; - first.prev = cl; - } - first = cl; - return cl; - } - - private static synchronized boolean remove(Cleaner cl) { - - // If already removed, do nothing - if (cl.next == cl) - return false; - - // Update list - if (first == cl) { - if (cl.next != null) - first = cl.next; - else - first = cl.prev; - } - if (cl.next != null) - cl.next.prev = cl.prev; - if (cl.prev != null) - cl.prev.next = cl.next; - - // Indicate removal by pointing the cleaner to itself - cl.next = cl; - cl.prev = cl; - return true; - - } - - private final Runnable thunk; - - private Cleaner(Object referent, Runnable thunk) { - super(referent, dummyQueue); - this.thunk = thunk; - } - - /** - * Creates a new cleaner. - * - * @param ob the referent object to be cleaned - * @param thunk - * The cleanup code to be run when the cleaner is invoked. The - * cleanup code is run directly from the reference-handler thread, - * so it should be as simple and straightforward as possible. - * - * @return The new cleaner - */ - public static Cleaner create(Object ob, Runnable thunk) { - if (thunk == null) - return null; - return add(new Cleaner(ob, thunk)); - } - - /** - * Runs this cleaner, if it has not been run before. - */ - public void clean() { - if (!remove(this)) - return; - try { - thunk.run(); - } catch (final Throwable x) { - if (System.err != null) { - new Error("Cleaner terminated abnormally", x) - .printStackTrace(); - } - System.exit(1); - } - } -} diff --git a/test/jdk/jdk/internal/ref/Cleaner/ExitOnThrow.java b/test/jdk/jdk/internal/ref/Cleaner/ExitOnThrow.java deleted file mode 100644 index 7e0ab4685d15f..0000000000000 --- a/test/jdk/jdk/internal/ref/Cleaner/ExitOnThrow.java +++ /dev/null @@ -1,64 +0,0 @@ -/* - * Copyright (c) 2003, 2024, Oracle and/or its affiliates. All rights reserved. - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This code is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 only, as - * published by the Free Software Foundation. - * - * This code is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * version 2 for more details (a copy is included in the LICENSE file that - * accompanied this code). - * - * You should have received a copy of the GNU General Public License version - * 2 along with this work; if not, write to the Free Software Foundation, - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA - * or visit www.oracle.com if you need additional information or have any - * questions. - */ - -/* - * @test - * @bug 4954921 8009259 - * @library /test/lib - * @modules java.base/jdk.internal.ref - * @build jdk.test.lib.Utils - * jdk.test.lib.Asserts - * jdk.test.lib.JDKToolFinder - * jdk.test.lib.JDKToolLauncher - * jdk.test.lib.Platform - * jdk.test.lib.process.* - * @run main ExitOnThrow - * @summary Ensure that if a cleaner throws an exception then the VM exits - */ - -import jdk.internal.ref.Cleaner; - -import jdk.test.lib.process.ProcessTools; - -public class ExitOnThrow { - - public static void main(String[] args) throws Exception { - if (args.length == 0) { - ProcessTools.executeTestJava("--add-exports", "java.base/jdk.internal.ref=ALL-UNNAMED", - "ExitOnThrow", - "-executeCleaner") - .outputTo(System.out) - .errorTo(System.out) - .shouldHaveExitValue(1) - .shouldContain("java.lang.RuntimeException: Foo!"); - } else { - Cleaner.create(new Object(), - () -> { throw new RuntimeException("Foo!"); } ); - while (true) { - System.gc(); - Thread.sleep(100); - } - } - } - -}