001    /**
002     * Copyright (c) 2000-2013 Liferay, Inc. All rights reserved.
003     *
004     * The contents of this file are subject to the terms of the Liferay Enterprise
005     * Subscription License ("License"). You may not use this file except in
006     * compliance with the License. You can obtain a copy of the License by
007     * contacting Liferay, Inc. See the License for the specific language governing
008     * permissions and limitations under the License, including but not limited to
009     * distribution rights of the Software.
010     *
011     *
012     *
013     */
014    
015    package com.liferay.portal.kernel.util;
016    
017    import com.liferay.portal.kernel.io.ProtectedObjectInputStream;
018    import com.liferay.portal.kernel.io.unsync.UnsyncByteArrayInputStream;
019    import com.liferay.portal.kernel.io.unsync.UnsyncByteArrayOutputStream;
020    import com.liferay.portal.kernel.log.Log;
021    import com.liferay.portal.kernel.log.LogFactoryUtil;
022    
023    import java.io.ObjectInputStream;
024    import java.io.ObjectOutputStream;
025    
026    /**
027     * @author Brian Wing Shun Chan
028     */
029    public class Base64 {
030    
031            public static byte[] decode(String base64) {
032                    if (Validator.isNull(base64)) {
033                            return new byte[0];
034                    }
035    
036                    int pad = 0;
037    
038                    for (int i = base64.length() - 1; base64.charAt(i) == CharPool.EQUAL;
039                                    i--) {
040    
041                            pad++;
042                    }
043    
044                    int length = (base64.length() * 6) / 8 - pad;
045                    byte[] raw = new byte[length];
046                    int rawindex = 0;
047    
048                    for (int i = 0; i < base64.length(); i += 4) {
049                            int block = getValue(base64.charAt(i)) << 18;
050    
051                            block += getValue(base64.charAt(i + 1)) << 12;
052                            block += getValue(base64.charAt(i + 2)) << 6;
053                            block += getValue(base64.charAt(i + 3));
054    
055                            for (int j = 0; j < 3 && rawindex + j < raw.length; j++) {
056                                    raw[rawindex + j] = (byte)(block >> 8 * (2 - j) & 0xff);
057                            }
058    
059                            rawindex += 3;
060                    }
061    
062                    return raw;
063            }
064    
065            public static String encode(byte[] raw) {
066                    return encode(raw, 0, raw.length);
067            }
068    
069            public static String encode(byte[] raw, int offset, int length) {
070                    int lastIndex = Math.min(raw.length, offset + length);
071    
072                    StringBuilder sb = new StringBuilder(
073                            ((lastIndex - offset) / 3 + 1) * 4);
074    
075                    for (int i = offset; i < lastIndex; i += 3) {
076                            sb.append(encodeBlock(raw, i, lastIndex));
077                    }
078    
079                    return sb.toString();
080            }
081    
082            public static String fromURLSafe(String base64) {
083                    return StringUtil.replace(
084                            base64,
085                            new String[] {
086                                    StringPool.MINUS, StringPool.STAR, StringPool.UNDERLINE
087                            },
088                            new String[] {
089                                    StringPool.PLUS, StringPool.EQUAL, StringPool.SLASH
090                            });
091            }
092    
093            public static String objectToString(Object o) {
094                    if (o == null) {
095                            return null;
096                    }
097    
098                    UnsyncByteArrayOutputStream ubaos = new UnsyncByteArrayOutputStream(
099                            32000);
100    
101                    try {
102                            ObjectOutputStream os = new ObjectOutputStream(ubaos);
103    
104                            os.flush();
105                            os.writeObject(o);
106                            os.flush();
107                    }
108                    catch (Exception e) {
109                            _log.error(e, e);
110                    }
111    
112                    return encode(ubaos.unsafeGetByteArray(), 0, ubaos.size());
113            }
114    
115            public static Object stringToObject(String s) {
116                    return _stringToObject(s, null, false);
117            }
118    
119            public static Object stringToObject(String s, ClassLoader classLoader) {
120                    return _stringToObject(s, classLoader, false);
121            }
122    
123            public static Object stringToObjectSilent(String s) {
124                    return _stringToObject(s, null, true);
125            }
126    
127            public static Object stringToObjectSilent(
128                    String s, ClassLoader classLoader) {
129    
130                    return _stringToObject(s, classLoader, true);
131            }
132    
133            public static String toURLSafe(String base64) {
134                    return StringUtil.replace(
135                            base64,
136                            new String[] {
137                                    StringPool.PLUS, StringPool.EQUAL, StringPool.SLASH
138                            },
139                            new String[] {
140                                    StringPool.MINUS, StringPool.STAR, StringPool.UNDERLINE
141                            });
142            }
143    
144            protected static char[] encodeBlock(byte[] raw, int offset, int lastIndex) {
145                    int block = 0;
146                    int slack = lastIndex - offset - 1;
147                    int end = slack < 2 ? slack : 2;
148    
149                    for (int i = 0; i <= end; i++) {
150                            byte b = raw[offset + i];
151    
152                            int neuter = b >= 0 ? ((int) (b)) : b + 256;
153                            block += neuter << 8 * (2 - i);
154                    }
155    
156                    char[] base64 = new char[4];
157    
158                    for (int i = 0; i < 4; i++) {
159                            int sixbit = block >>> 6 * (3 - i) & 0x3f;
160                            base64[i] = getChar(sixbit);
161                    }
162    
163                    if (slack < 1) {
164                            base64[2] = CharPool.EQUAL;
165                    }
166    
167                    if (slack < 2) {
168                            base64[3] = CharPool.EQUAL;
169                    }
170    
171                    return base64;
172            }
173    
174            protected static char getChar(int sixbit) {
175                    if ((sixbit >= 0) && (sixbit <= 25)) {
176                            return (char)(65 + sixbit);
177                    }
178    
179                    if ((sixbit >= 26) && (sixbit <= 51)) {
180                            return (char)(97 + (sixbit - 26));
181                    }
182    
183                    if ((sixbit >= 52) && (sixbit <= 61)) {
184                            return (char)(48 + (sixbit - 52));
185                    }
186    
187                    if (sixbit == 62) {
188                            return CharPool.PLUS;
189                    }
190    
191                    return sixbit != 63 ? CharPool.QUESTION : CharPool.SLASH;
192            }
193    
194            protected static int getValue(char c) {
195                    if ((c >= CharPool.UPPER_CASE_A) && (c <= CharPool.UPPER_CASE_Z)) {
196                            return c - 65;
197                    }
198    
199                    if ((c >= CharPool.LOWER_CASE_A) && (c <= CharPool.LOWER_CASE_Z)) {
200                            return (c - 97) + 26;
201                    }
202    
203                    if ((c >= CharPool.NUMBER_0) && (c <= CharPool.NUMBER_9)) {
204                            return (c - 48) + 52;
205                    }
206    
207                    if (c == CharPool.PLUS) {
208                            return 62;
209                    }
210    
211                    if (c == CharPool.SLASH) {
212                            return 63;
213                    }
214    
215                    return c != CharPool.EQUAL ? -1 : 0;
216            }
217    
218            private static Object _stringToObject(
219                    String s, ClassLoader classLoader, boolean silent) {
220    
221                    if (s == null) {
222                            return null;
223                    }
224    
225                    byte[] bytes = decode(s);
226    
227                    UnsyncByteArrayInputStream ubais = new UnsyncByteArrayInputStream(
228                            bytes);
229    
230                    try {
231                            ObjectInputStream is = null;
232    
233                            if (classLoader == null) {
234                                    is = new ProtectedObjectInputStream(ubais);
235                            }
236                            else {
237                                    is = new ProtectedClassLoaderObjectInputStream(
238                                            ubais, classLoader);
239                            }
240    
241                            return is.readObject();
242                    }
243                    catch (Exception e) {
244                            if (!silent) {
245                                    _log.error(e, e);
246                            }
247                    }
248    
249                    return null;
250            }
251    
252            private static Log _log = LogFactoryUtil.getLog(Base64.class);
253    
254    }