1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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8  * particular file as subject to the "Classpath" exception as provided
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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).
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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 
force(FileDescriptor fd, boolean metaData)39     abstract int force(FileDescriptor fd, boolean metaData) throws IOException;
40 
truncate(FileDescriptor fd, long size)41     abstract int truncate(FileDescriptor fd, long size) throws IOException;
42 
size(FileDescriptor fd)43     abstract long size(FileDescriptor fd) throws IOException;
44 
lock(FileDescriptor fd, boolean blocking, long pos, long size, boolean shared)45     abstract int lock(FileDescriptor fd, boolean blocking, long pos, long size,
46                        boolean shared) throws IOException;
47 
release(FileDescriptor fd, long pos, long size)48     abstract void release(FileDescriptor fd, long pos, long size)
49         throws IOException;
50 
51     /**
52      * Returns a dup of fd if a file descriptor is required for
53      * memory-mapping operations, otherwise returns an invalid
54      * FileDescriptor (meaning a newly allocated FileDescriptor)
55      */
duplicateForMapping(FileDescriptor fd)56     abstract FileDescriptor duplicateForMapping(FileDescriptor fd)
57         throws IOException;
58 
canTransferToDirectly(SelectableChannel sc)59     abstract boolean canTransferToDirectly(SelectableChannel sc);
60 
transferToDirectlyNeedsPositionLock()61     abstract boolean transferToDirectlyNeedsPositionLock();
62 }
63