1 /*
2  * Copyright (c) 2005, 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 
31 /*
32  * Represents a key to a specific file on Solaris or Linux
33  */
34 public class FileKey {
35 
36     private long st_dev;    // ID of device
37     private long st_ino;    // Inode number
38 
FileKey()39     private FileKey() { }
40 
create(FileDescriptor fd)41     public static FileKey create(FileDescriptor fd) {
42         FileKey fk = new FileKey();
43         try {
44             fk.init(fd);
45         } catch (IOException ioe) {
46             throw new Error(ioe);
47         }
48         return fk;
49     }
50 
hashCode()51     public int hashCode() {
52         return (int)(st_dev ^ (st_dev >>> 32)) +
53                (int)(st_ino ^ (st_ino >>> 32));
54     }
55 
equals(Object obj)56     public boolean equals(Object obj) {
57         if (obj == this)
58             return true;
59         if (!(obj instanceof FileKey))
60             return false;
61         FileKey other = (FileKey)obj;
62         if ((this.st_dev != other.st_dev) ||
63             (this.st_ino != other.st_ino)) {
64             return false;
65         }
66         return true;
67     }
68 
init(FileDescriptor fd)69     private native void init(FileDescriptor fd) throws IOException;
70 }
71