1 /*
   2  * Copyright (c) 2002, 2012, 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 import jdk.internal.misc.Strands;
  32 
  33 class NativeThread {
  34     private static final long FIBER_ID = -1L;
  35 
  36     static long current() {
  37         Object s = Strands.currentStrand();
  38         if (s instanceof Fiber) {
  39             return FIBER_ID;
  40         } else {
  41             return 0;
  42         }
  43     }
  44 
  45     static long currentKernelThread() {
  46         return 0;
  47     }
  48 
  49     static void signal(long tid) {
  50         throw new UnsupportedOperationException();
  51     }
  52 
  53     static boolean isFiber(long tid) {
  54         return (tid == FIBER_ID);
  55     }
  56 
  57     static boolean isKernelThread(long tid) {
  58         return false;
  59     }
  60 
  61 }