1
19
20 package com.liferay.portal.kernel.util;
21
22 import com.liferay.portal.kernel.log.Log;
23 import com.liferay.portal.kernel.log.LogFactoryUtil;
24
25 import java.io.BufferedInputStream;
26 import java.io.BufferedOutputStream;
27 import java.io.ByteArrayInputStream;
28 import java.io.IOException;
29 import java.io.ObjectInputStream;
30 import java.io.ObjectOutputStream;
31
32
38 public class Base64 {
39
40 protected static char getChar(int sixbit) {
41 if (sixbit >= 0 && sixbit <= 25) {
42 return (char)(65 + sixbit);
43 }
44
45 if (sixbit >= 26 && sixbit <= 51) {
46 return (char)(97 + (sixbit - 26));
47 }
48
49 if (sixbit >= 52 && sixbit <= 61) {
50 return (char)(48 + (sixbit - 52));
51 }
52
53 if (sixbit == 62) {
54 return '+';
55 }
56
57 return sixbit != 63 ? '?' : '/';
58 }
59
60 protected static int getValue(char c) {
61 if (c >= 'A' && c <= 'Z') {
62 return c - 65;
63 }
64
65 if (c >= 'a' && c <= 'z') {
66 return (c - 97) + 26;
67 }
68
69 if (c >= '0' && c <= '9') {
70 return (c - 48) + 52;
71 }
72
73 if (c == '+') {
74 return 62;
75 }
76
77 if (c == '/') {
78 return 63;
79 }
80
81 return c != '=' ? -1 : 0;
82 }
83
84 public static String encode(byte raw[]) {
85 StringBuilder encoded = new StringBuilder();
86
87 for (int i = 0; i < raw.length; i += 3) {
88 encoded.append(encodeBlock(raw, i));
89 }
90
91 return encoded.toString();
92 }
93
94 protected static char[] encodeBlock(byte raw[], int offset) {
95 int block = 0;
96 int slack = raw.length - offset - 1;
97 int end = slack < 2 ? slack : 2;
98
99 for (int i = 0; i <= end; i++) {
100 byte b = raw[offset + i];
101
102 int neuter = b >= 0 ? ((int) (b)) : b + 256;
103 block += neuter << 8 * (2 - i);
104 }
105
106 char base64[] = new char[4];
107
108 for (int i = 0; i < 4; i++) {
109 int sixbit = block >>> 6 * (3 - i) & 0x3f;
110 base64[i] = getChar(sixbit);
111 }
112
113 if (slack < 1) {
114 base64[2] = '=';
115 }
116
117 if (slack < 2) {
118 base64[3] = '=';
119 }
120
121 return base64;
122 }
123
124 public static byte[] decode(String base64) {
125 if (Validator.isNull(base64)) {
126 return new byte[0];
127 }
128
129 int pad = 0;
130
131 for (int i = base64.length() - 1; base64.charAt(i) == '='; i--) {
132 pad++;
133 }
134
135 int length = (base64.length() * 6) / 8 - pad;
136 byte raw[] = new byte[length];
137 int rawindex = 0;
138
139 for (int i = 0; i < base64.length(); i += 4) {
140 int block = (getValue(base64.charAt(i)) << 18) +
141 (getValue(base64.charAt(i + 1)) << 12) +
142 (getValue(base64.charAt(i + 2)) << 6) +
143 getValue(base64.charAt(i + 3));
144
145 for (int j = 0; j < 3 && rawindex + j < raw.length; j++) {
146 raw[rawindex + j] = (byte)(block >> 8 * (2 - j) & 0xff);
147 }
148
149 rawindex += 3;
150 }
151
152 return raw;
153 }
154
155 public static String objectToString(Object o) {
156 if (o == null) {
157 return null;
158 }
159
160 ByteArrayMaker bam = new ByteArrayMaker(32000);
161
162 try {
163 ObjectOutputStream os = new ObjectOutputStream(
164 new BufferedOutputStream(bam));
165
166 os.flush();
167 os.writeObject(o);
168 os.flush();
169 }
170 catch (IOException e) {
171 _log.error(e.getMessage());
172 }
173
174 return encode(bam.toByteArray());
175 }
176
177 public static Object stringToObject(String s) {
178 if (s == null) {
179 return null;
180 }
181
182 byte bytes[] = decode(s);
183
184 ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
185
186 try {
187 ObjectInputStream is = new ObjectInputStream(
188 new BufferedInputStream(bais));
189
190 return is.readObject();
191 }
192 catch (Exception e) {
193 _log.error(e.getMessage());
194 }
195
196 return null;
197 }
198
199 private static Log _log = LogFactoryUtil.getLog(Base64.class);
200
201 }