1/*
2 * Copyright (c) 2007, 2009, 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
26package java.nio.file;
27
28import java.io.IOException;
29
30/**
31 * Thrown when a file system operation fails on one or two files. This class is
32 * the general class for file system exceptions.
33 *
34 * @since 1.7
35 */
36
37public class FileSystemException
38    extends IOException
39{
40    static final long serialVersionUID = -3055425747967319812L;
41
42    private final String file;
43    private final String other;
44
45    /**
46     * Constructs an instance of this class. This constructor should be used
47     * when an operation involving one file fails and there isn't any additional
48     * information to explain the reason.
49     *
50     * @param   file
51     *          a string identifying the file or {@code null} if not known.
52     */
53    public FileSystemException(String file) {
54        super((String)null);
55        this.file = file;
56        this.other = null;
57    }
58
59    /**
60     * Constructs an instance of this class. This constructor should be used
61     * when an operation involving two files fails, or there is additional
62     * information to explain the reason.
63     *
64     * @param   file
65     *          a string identifying the file or {@code null} if not known.
66     * @param   other
67     *          a string identifying the other file or {@code null} if there
68     *          isn't another file or if not known
69     * @param   reason
70     *          a reason message with additional information or {@code null}
71     */
72    public FileSystemException(String file, String other, String reason) {
73        super(reason);
74        this.file = file;
75        this.other = other;
76    }
77
78    /**
79     * Returns the file used to create this exception.
80     *
81     * @return  the file (can be {@code null})
82     */
83    public String getFile() {
84        return file;
85    }
86
87    /**
88     * Returns the other file used to create this exception.
89     *
90     * @return  the other file (can be {@code null})
91     */
92    public String getOtherFile() {
93        return other;
94    }
95
96    /**
97     * Returns the string explaining why the file system operation failed.
98     *
99     * @return  the string explaining why the file system operation failed
100     */
101    public String getReason() {
102        return super.getMessage();
103    }
104
105    /**
106     * Returns the detail message string.
107     */
108    @Override
109    public String getMessage() {
110        if (file == null && other == null)
111            return getReason();
112        StringBuilder sb = new StringBuilder();
113        if (file != null)
114            sb.append(file);
115        if (other != null) {
116            sb.append(" -> ");
117            sb.append(other);
118        }
119        if (getReason() != null) {
120            sb.append(": ");
121            sb.append(getReason());
122        }
123        return sb.toString();
124    }
125}
126