2362N/A * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved. 0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 0N/A * This code is free software; you can redistribute it and/or modify it 0N/A * under the terms of the GNU General Public License version 2 only, as 2362N/A * published by the Free Software Foundation. Oracle designates this 0N/A * particular file as subject to the "Classpath" exception as provided 2362N/A * by Oracle in the LICENSE file that accompanied this code. 0N/A * This code is distributed in the hope that it will be useful, but WITHOUT 0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 0N/A * version 2 for more details (a copy is included in the LICENSE file that 0N/A * accompanied this code). 0N/A * You should have received a copy of the GNU General Public License version 0N/A * 2 along with this work; if not, write to the Free Software Foundation, 0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 2362N/A * or visit www.oracle.com if you need additional information or have any 0N/A * Small class to assist in properly closing an ImageInputStream instance 0N/A * prior to garbage collection. The ImageInputStreamImpl class defines a 0N/A * finalize() method, but in a number of its public subclasses 0N/A * (e.g. FileImageInputStream) we override the finalize() method to be 0N/A * empty for performance reasons, and instead rely on the Disposer mechanism 0N/A * is instantiated directly (e.g. new FileImageInputStream()) but in the 0N/A * unlikely case where a user defines their own subclass of one of those 0N/A * streams, we need some way to get back to the behavior of 0N/A * ImageInputStreamImpl, which will call close() as part of finalization. 0N/A * Typically an Image{Input,Output}Stream will construct an instance of 0N/A * StreamFinalizer in its constructor if it detects that it has been 0N/A * subclassed by the user. The ImageInputStream instance will hold a 0N/A * reference to the StreamFinalizer, and the StreamFinalizer will hold a 0N/A * reference back to the ImageInputStream from which it was created. When 0N/A * both are no longer reachable, the StreamFinalizer.finalize() method will 0N/A * be called, which will take care of closing down the ImageInputStream. 0N/A * Clearly this is a bit of a hack, but it will likely only be used in the 0N/A * rarest of circumstances: when a user has subclassed one of the public 0N/A * stream classes. (It should be no worse than the old days when the public 0N/A * stream classes had non-empty finalize() methods.)