1/* 2 * Copyright (c) 2003, 2017, 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. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24/* 25 * A collection of utility methods used by the SelectorProvider.inheritedChannel 26 * unit tests. 27 */ 28import java.io.File; 29import java.io.FileDescriptor; 30import java.lang.reflect.Field; 31import java.nio.channels.DatagramChannel; 32import java.nio.channels.ServerSocketChannel; 33import java.nio.channels.SocketChannel; 34 35public class Util { 36 37 private static Object get(String className, String fieldName, Object o) throws Exception { 38 Class cl = Class.forName(className); 39 Field fld = cl.getDeclaredField(fieldName); 40 fld.setAccessible(true); 41 return fld.get(o); 42 } 43 44 private static int fdVal(FileDescriptor fdObj) throws Exception { 45 Object fdVal = get("java.io.FileDescriptor", "fd", fdObj); 46 return ((Integer)fdVal).intValue(); 47 } 48 49 /* 50 * Return the file descriptor underlying a given SocketChannel 51 */ 52 public static int getFD(SocketChannel sc) { 53 try { 54 Object fdObj = get("sun.nio.ch.SocketChannelImpl", "fd", sc); 55 return fdVal((FileDescriptor)fdObj); 56 } catch (Exception x) { 57 x.printStackTrace(); 58 throw new InternalError(x.getMessage()); 59 } 60 } 61 62 /* 63 * Return the file descriptor underlying a given ServerSocketChannel 64 */ 65 public static int getFD(ServerSocketChannel ssc) { 66 try { 67 Object fdObj = get("sun.nio.ch.ServerSocketChannelImpl", "fd", ssc); 68 return fdVal((FileDescriptor)fdObj); 69 } catch (Exception x) { 70 x.printStackTrace(); 71 throw new InternalError(x.getMessage()); 72 } 73 } 74 75 /* 76 * Return the file descriptor underlying a given DatagramChannel 77 */ 78 public static int getFD(DatagramChannel dc) { 79 try { 80 Object fdObj = get("sun.nio.ch.DatagramChannelImpl", "fd", dc); 81 return fdVal((FileDescriptor)fdObj); 82 } catch (Exception x) { 83 x.printStackTrace(); 84 throw new InternalError(x.getMessage()); 85 } 86 } 87 88 /* 89 * Return the "java" command and any initial arguments to start the runtime 90 * in the current configuration. 91 */ 92 public static String javaCommand() { 93 return System.getProperty("java.home") + File.separator + "bin" + 94 File.separator + "java"; 95 } 96} 97