1 /* 2 * Copyright (c) 2007, 2018, 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.FileDescriptor; 29 import java.io.IOException; 30 import java.nio.channels.SelectableChannel; 31 32 abstract class FileDispatcher extends NativeDispatcher { 33 34 public static final int NO_LOCK = -1; // Failed to lock 35 public static final int LOCKED = 0; // Obtained requested lock 36 public static final int RET_EX_LOCK = 1; // Obtained exclusive lock 37 public static final int INTERRUPTED = 2; // Request interrupted 38 39 /** 40 * Sets or reports this file's position 41 * If offset is -1, the current position is returned 42 * otherwise the position is set to offset. 43 */ seek(FileDescriptor fd, long offset)44 abstract long seek(FileDescriptor fd, long offset) throws IOException; 45 force(FileDescriptor fd, boolean metaData)46 abstract int force(FileDescriptor fd, boolean metaData) throws IOException; 47 truncate(FileDescriptor fd, long size)48 abstract int truncate(FileDescriptor fd, long size) throws IOException; 49 size(FileDescriptor fd)50 abstract long size(FileDescriptor fd) throws IOException; 51 lock(FileDescriptor fd, boolean blocking, long pos, long size, boolean shared)52 abstract int lock(FileDescriptor fd, boolean blocking, long pos, long size, 53 boolean shared) throws IOException; 54 release(FileDescriptor fd, long pos, long size)55 abstract void release(FileDescriptor fd, long pos, long size) 56 throws IOException; 57 58 /** 59 * Returns a dup of fd if a file descriptor is required for 60 * memory-mapping operations, otherwise returns an invalid 61 * FileDescriptor (meaning a newly allocated FileDescriptor) 62 */ duplicateForMapping(FileDescriptor fd)63 abstract FileDescriptor duplicateForMapping(FileDescriptor fd) 64 throws IOException; 65 canTransferToDirectly(SelectableChannel sc)66 abstract boolean canTransferToDirectly(SelectableChannel sc); 67 transferToDirectlyNeedsPositionLock()68 abstract boolean transferToDirectlyNeedsPositionLock(); 69 setDirectIO(FileDescriptor fd, String path)70 abstract int setDirectIO(FileDescriptor fd, String path); 71 } 72