1/*
2 * Copyright 2009 Mike Cumings
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *   http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.kenai.jbosh;
18
19/**
20 * Data type representing the getValue of the {@code ver} attribute of the
21 * {@code bosh} element.
22 */
23final class AttrVersion extends AbstractAttr<String> implements Comparable {
24
25    /**
26     * Default value if none is provided.
27     */
28    private static final AttrVersion DEFAULT;
29    static {
30        try {
31            DEFAULT = createFromString("1.8");
32        } catch (BOSHException boshx) {
33            throw(new IllegalStateException(boshx));
34        }
35    }
36
37    /**
38     * Major portion of the version.
39     */
40    private final int major;
41
42    /**
43     * Minor portion of the version.
44     */
45    private final int minor;
46
47    /**
48     * Creates a new attribute object.
49     *
50     * @param val attribute getValue
51     * @throws BOSHException on parse or validation failure
52     */
53    private AttrVersion(final String val) throws BOSHException {
54        super(val);
55
56        int idx = val.indexOf('.');
57        if (idx <= 0) {
58            throw(new BOSHException(
59                    "Illegal ver attribute value (not in major.minor form): "
60                    + val));
61        }
62
63        String majorStr = val.substring(0, idx);
64        try {
65            major = Integer.parseInt(majorStr);
66        } catch (NumberFormatException nfx) {
67            throw(new BOSHException(
68                    "Could not parse ver attribute value (major ver): "
69                    + majorStr,
70                    nfx));
71        }
72        if (major < 0) {
73            throw(new BOSHException(
74                    "Major version may not be < 0"));
75        }
76
77        String minorStr = val.substring(idx + 1);
78        try {
79            minor = Integer.parseInt(minorStr);
80        } catch (NumberFormatException nfx) {
81            throw(new BOSHException(
82                    "Could not parse ver attribute value (minor ver): "
83                    + minorStr,
84                    nfx));
85        }
86        if (minor < 0) {
87            throw(new BOSHException(
88                    "Minor version may not be < 0"));
89        }
90    }
91
92    /**
93     * Get the version of specifcation that we support.
94     *
95     * @return max spec version the code supports
96     */
97    static AttrVersion getSupportedVersion() {
98        return DEFAULT;
99    }
100
101    /**
102     * Creates a new attribute instance from the provided String.
103     *
104     * @param str string representation of the attribute
105     * @return attribute instance or {@code null} if provided string is
106     *  {@code null}
107     * @throws BOSHException on parse or validation failure
108     */
109    static AttrVersion createFromString(final String str)
110    throws BOSHException {
111        if (str == null) {
112            return null;
113        } else {
114            return new AttrVersion(str);
115        }
116    }
117
118    /**
119     * Returns the 'major' portion of the version number.
120     *
121     * @return major digits only
122     */
123    int getMajor() {
124        return major;
125    }
126
127    /**
128     * Returns the 'minor' portion of the version number.
129     *
130     * @return minor digits only
131     */
132    int getMinor() {
133        return minor;
134    }
135
136    ///////////////////////////////////////////////////////////////////////////
137    // Comparable interface:
138
139    /**
140     * {@inheritDoc}
141     *
142     * @param otherObj object to compare to
143     * @return -1, 0, or 1
144     */
145    @Override
146    public int compareTo(final Object otherObj) {
147        if (otherObj instanceof AttrVersion) {
148            AttrVersion other = (AttrVersion) otherObj;
149            if (major < other.major) {
150                return -1;
151            } else if (major > other.major) {
152                return 1;
153            } else if (minor < other.minor) {
154                return -1;
155            } else if (minor > other.minor) {
156                return 1;
157            } else {
158                return 0;
159            }
160        } else {
161            return 0;
162        }
163    }
164
165}
166