1 /* 2 * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package sun.nio.ch; 27 28 29 // Signalling operations on native threads 30 // 31 // On some operating systems (e.g., Linux), closing a channel while another 32 // thread is blocked in an I/O operation upon that channel does not cause that 33 // thread to be released. This class provides access to the native threads 34 // upon which Java threads are built, and defines a simple signal mechanism 35 // that can be used to release a native thread from a blocking I/O operation. 36 // On systems that do not require this type of signalling, the current() method 37 // always returns -1 and the signal(long) method has no effect. 38 39 40 public class NativeThread { 41 42 // Returns an opaque token representing the native thread underlying the 43 // invoking Java thread. On systems that do not require signalling, this 44 // method always returns -1. 45 // current()46 public static native long current(); 47 48 // Signals the given native thread so as to release it from a blocking I/O 49 // operation. On systems that do not require signalling, this method has 50 // no effect. 51 // signal(long nt)52 public static native void signal(long nt); 53 } 54