--- old/src/java.base/share/classes/jdk/internal/ref/Cleaner.java 2016-03-23 13:44:06.660025830 +0100 +++ /dev/null 2016-03-23 07:44:20.375055489 +0100 @@ -1,164 +0,0 @@ -/* - * Copyright (c) 2003, 2013, 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.*; -import java.security.AccessController; -import java.security.PrivilegedAction; - - -/** - * 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