1 /* 2 * Copyright (c) 2000, 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 import java.io.*; 29 30 /** 31 * Allows different platforms to call different native methods 32 * for read and write operations. 33 */ 34 35 abstract class NativeDispatcher 36 { 37 read(FileDescriptor fd, long address, int len)38 abstract int read(FileDescriptor fd, long address, int len) 39 throws IOException; 40 41 /** 42 * Returns {@code true} if pread/pwrite needs to be synchronized with 43 * position sensitive methods. 44 */ needsPositionLock()45 boolean needsPositionLock() { 46 return false; 47 } 48 pread(FileDescriptor fd, long address, int len, long position)49 int pread(FileDescriptor fd, long address, int len, long position) 50 throws IOException 51 { 52 throw new IOException("Operation Unsupported"); 53 } 54 readv(FileDescriptor fd, long address, int len)55 abstract long readv(FileDescriptor fd, long address, int len) 56 throws IOException; 57 write(FileDescriptor fd, long address, int len)58 abstract int write(FileDescriptor fd, long address, int len) 59 throws IOException; 60 pwrite(FileDescriptor fd, long address, int len, long position)61 int pwrite(FileDescriptor fd, long address, int len, long position) 62 throws IOException 63 { 64 throw new IOException("Operation Unsupported"); 65 } 66 writev(FileDescriptor fd, long address, int len)67 abstract long writev(FileDescriptor fd, long address, int len) 68 throws IOException; 69 close(FileDescriptor fd)70 abstract void close(FileDescriptor fd) throws IOException; 71 72 // Prepare the given fd for closing by duping it to a known internal fd 73 // that's already closed. This is necessary on some operating systems 74 // (Solaris and Linux) to prevent fd recycling. 75 // preClose(FileDescriptor fd)76 void preClose(FileDescriptor fd) throws IOException { 77 // Do nothing by default; this is only needed on Unix 78 } 79 80 } 81