1/*
2 * Copyright (C) 2007 Esmertec AG.
3 * Copyright (C) 2007 The Android Open Source Project
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *      http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18package com.google.android.mms.pdu;
19
20import java.io.UnsupportedEncodingException;
21import java.util.HashMap;
22
23public class CharacterSets {
24    /**
25     * IANA assigned MIB enum numbers.
26     *
27     * From wap-230-wsp-20010705-a.pdf
28     * Any-charset = <Octet 128>
29     * Equivalent to the special RFC2616 charset value "*"
30     */
31    public static final int ANY_CHARSET = 0x00;
32    public static final int US_ASCII    = 0x03;
33    public static final int ISO_8859_1  = 0x04;
34    public static final int ISO_8859_2  = 0x05;
35    public static final int ISO_8859_3  = 0x06;
36    public static final int ISO_8859_4  = 0x07;
37    public static final int ISO_8859_5  = 0x08;
38    public static final int ISO_8859_6  = 0x09;
39    public static final int ISO_8859_7  = 0x0A;
40    public static final int ISO_8859_8  = 0x0B;
41    public static final int ISO_8859_9  = 0x0C;
42    public static final int SHIFT_JIS   = 0x11;
43    public static final int UTF_8       = 0x6A;
44    public static final int BIG5        = 0x07EA;
45    public static final int UCS2        = 0x03E8;
46    public static final int UTF_16      = 0x03F7;
47
48    /**
49     * If the encoding of given data is unsupported, use UTF_8 to decode it.
50     */
51    public static final int DEFAULT_CHARSET = UTF_8;
52
53    /**
54     * Array of MIB enum numbers.
55     */
56    private static final int[] MIBENUM_NUMBERS = {
57        ANY_CHARSET,
58        US_ASCII,
59        ISO_8859_1,
60        ISO_8859_2,
61        ISO_8859_3,
62        ISO_8859_4,
63        ISO_8859_5,
64        ISO_8859_6,
65        ISO_8859_7,
66        ISO_8859_8,
67        ISO_8859_9,
68        SHIFT_JIS,
69        UTF_8,
70        BIG5,
71        UCS2,
72        UTF_16,
73    };
74
75    /**
76     * The Well-known-charset Mime name.
77     */
78    public static final String MIMENAME_ANY_CHARSET = "*";
79    public static final String MIMENAME_US_ASCII    = "us-ascii";
80    public static final String MIMENAME_ISO_8859_1  = "iso-8859-1";
81    public static final String MIMENAME_ISO_8859_2  = "iso-8859-2";
82    public static final String MIMENAME_ISO_8859_3  = "iso-8859-3";
83    public static final String MIMENAME_ISO_8859_4  = "iso-8859-4";
84    public static final String MIMENAME_ISO_8859_5  = "iso-8859-5";
85    public static final String MIMENAME_ISO_8859_6  = "iso-8859-6";
86    public static final String MIMENAME_ISO_8859_7  = "iso-8859-7";
87    public static final String MIMENAME_ISO_8859_8  = "iso-8859-8";
88    public static final String MIMENAME_ISO_8859_9  = "iso-8859-9";
89    public static final String MIMENAME_SHIFT_JIS   = "shift_JIS";
90    public static final String MIMENAME_UTF_8       = "utf-8";
91    public static final String MIMENAME_BIG5        = "big5";
92    public static final String MIMENAME_UCS2        = "iso-10646-ucs-2";
93    public static final String MIMENAME_UTF_16      = "utf-16";
94
95    public static final String DEFAULT_CHARSET_NAME = MIMENAME_UTF_8;
96
97    /**
98     * Array of the names of character sets.
99     */
100    private static final String[] MIME_NAMES = {
101        MIMENAME_ANY_CHARSET,
102        MIMENAME_US_ASCII,
103        MIMENAME_ISO_8859_1,
104        MIMENAME_ISO_8859_2,
105        MIMENAME_ISO_8859_3,
106        MIMENAME_ISO_8859_4,
107        MIMENAME_ISO_8859_5,
108        MIMENAME_ISO_8859_6,
109        MIMENAME_ISO_8859_7,
110        MIMENAME_ISO_8859_8,
111        MIMENAME_ISO_8859_9,
112        MIMENAME_SHIFT_JIS,
113        MIMENAME_UTF_8,
114        MIMENAME_BIG5,
115        MIMENAME_UCS2,
116        MIMENAME_UTF_16,
117    };
118
119    private static final HashMap<Integer, String> MIBENUM_TO_NAME_MAP;
120    private static final HashMap<String, Integer> NAME_TO_MIBENUM_MAP;
121
122    static {
123        // Create the HashMaps.
124        MIBENUM_TO_NAME_MAP = new HashMap<Integer, String>();
125        NAME_TO_MIBENUM_MAP = new HashMap<String, Integer>();
126        assert(MIBENUM_NUMBERS.length == MIME_NAMES.length);
127        int count = MIBENUM_NUMBERS.length - 1;
128        for(int i = 0; i <= count; i++) {
129            MIBENUM_TO_NAME_MAP.put(MIBENUM_NUMBERS[i], MIME_NAMES[i]);
130            NAME_TO_MIBENUM_MAP.put(MIME_NAMES[i], MIBENUM_NUMBERS[i]);
131        }
132    }
133
134    private CharacterSets() {} // Non-instantiatable
135
136    /**
137     * Map an MIBEnum number to the name of the charset which this number
138     * is assigned to by IANA.
139     *
140     * @param mibEnumValue An IANA assigned MIBEnum number.
141     * @return The name string of the charset.
142     * @throws UnsupportedEncodingException
143     */
144    public static String getMimeName(int mibEnumValue)
145            throws UnsupportedEncodingException {
146        String name = MIBENUM_TO_NAME_MAP.get(mibEnumValue);
147        if (name == null) {
148            throw new UnsupportedEncodingException();
149        }
150        return name;
151    }
152
153    /**
154     * Map a well-known charset name to its assigned MIBEnum number.
155     *
156     * @param mimeName The charset name.
157     * @return The MIBEnum number assigned by IANA for this charset.
158     * @throws UnsupportedEncodingException
159     */
160    public static int getMibEnumValue(String mimeName)
161            throws UnsupportedEncodingException {
162        if(null == mimeName) {
163            return -1;
164        }
165
166        Integer mibEnumValue = NAME_TO_MIBENUM_MAP.get(mimeName);
167        if (mibEnumValue == null) {
168            throw new UnsupportedEncodingException();
169        }
170        return mibEnumValue;
171    }
172}
173