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1
21
22
27 package com.sun.mail.util;
28
29 import java.io.ByteArrayInputStream  ;
30 import java.io.ByteArrayOutputStream ;
31 import java.io.InputStream ;
32 import java.io.IOException ;
33
34 public class ASCIIUtility {
35
36 private ASCIIUtility() { }
38
39
46 public static int parseInt(byte[] b, int start, int end, int radix)
47 throws NumberFormatException {
48 if (b == null)
49 throw new NumberFormatException ("null");
50
51 int result = 0;
52 boolean negative = false;
53 int i = start;
54 int limit;
55 int multmin;
56 int digit;
57
58 if (end > start) {
59 if (b[i] == '-') {
60 negative = true;
61 limit = Integer.MIN_VALUE;
62 i++;
63 } else {
64 limit = -Integer.MAX_VALUE;
65 }
66 multmin = limit / radix;
67 if (i < end) {
68 digit = Character.digit((char)b[i++], radix);
69 if (digit < 0) {
70 throw new NumberFormatException (
71 "illegal number: " + toString(b, start, end)
72 );
73 } else {
74 result = -digit;
75 }
76 }
77 while (i < end) {
78 digit = Character.digit((char)b[i++], radix);
80 if (digit < 0) {
81 throw new NumberFormatException ("illegal number");
82 }
83 if (result < multmin) {
84 throw new NumberFormatException ("illegal number");
85 }
86 result *= radix;
87 if (result < limit + digit) {
88 throw new NumberFormatException ("illegal number");
89 }
90 result -= digit;
91 }
92 } else {
93 throw new NumberFormatException ("illegal number");
94 }
95 if (negative) {
96 if (i > start + 1) {
97 return result;
98 } else {
99 throw new NumberFormatException ("illegal number");
100 }
101 } else {
102 return -result;
103 }
104 }
105
106
111 public static int parseInt(byte[] b, int start, int end)
112 throws NumberFormatException {
113 return parseInt(b, start, end, 10);
114 }
115
116
123 public static long parseLong(byte[] b, int start, int end, int radix)
124 throws NumberFormatException {
125 if (b == null)
126 throw new NumberFormatException ("null");
127
128 long result = 0;
129 boolean negative = false;
130 int i = start;
131 long limit;
132 long multmin;
133 int digit;
134
135 if (end > start) {
136 if (b[i] == '-') {
137 negative = true;
138 limit = Long.MIN_VALUE;
139 i++;
140 } else {
141 limit = -Long.MAX_VALUE;
142 }
143 multmin = limit / radix;
144 if (i < end) {
145 digit = Character.digit((char)b[i++], radix);
146 if (digit < 0) {
147 throw new NumberFormatException (
148 "illegal number: " + toString(b, start, end)
149 );
150 } else {
151 result = -digit;
152 }
153 }
154 while (i < end) {
155 digit = Character.digit((char)b[i++], radix);
157 if (digit < 0) {
158 throw new NumberFormatException ("illegal number");
159 }
160 if (result < multmin) {
161 throw new NumberFormatException ("illegal number");
162 }
163 result *= radix;
164 if (result < limit + digit) {
165 throw new NumberFormatException ("illegal number");
166 }
167 result -= digit;
168 }
169 } else {
170 throw new NumberFormatException ("illegal number");
171 }
172 if (negative) {
173 if (i > start + 1) {
174 return result;
175 } else {
176 throw new NumberFormatException ("illegal number");
177 }
178 } else {
179 return -result;
180 }
181 }
182
183
188 public static long parseLong(byte[] b, int start, int end)
189 throws NumberFormatException {
190 return parseLong(b, start, end, 10);
191 }
192
193
198 public static String toString(byte[] b, int start, int end) {
199 int size = end - start;
200 char[] theChars = new char[size];
201
202 for (int i = 0, j = start; i < size; )
203 theChars[i++] = (char)(b[j++]&0xff);
204
205 return new String (theChars);
206 }
207
208 public static String toString(ByteArrayInputStream is) {
209 int size = is.available();
210 char[] theChars = new char[size];
211 byte[] bytes = new byte[size];
212
213 is.read(bytes, 0, size);
214 for (int i = 0; i < size;)
215 theChars[i] = (char)(bytes[i++]&0xff);
216
217 return new String (theChars);
218 }
219
220
221 public static byte[] getBytes(String s) {
222 char [] chars= s.toCharArray();
223 int size = chars.length;
224 byte[] bytes = new byte[size];
225
226 for (int i = 0; i < size;)
227 bytes[i] = (byte) chars[i++];
228 return bytes;
229 }
230
231 public static byte[] getBytes(InputStream is) throws IOException {
232
233 int len;
234 int size = 1024;
235 byte [] buf;
236
237
238 if (is instanceof ByteArrayInputStream ) {
239 size = is.available();
240 buf = new byte[size];
241 len = is.read(buf, 0, size);
242 }
243 else {
244 ByteArrayOutputStream bos = new ByteArrayOutputStream ();
245 buf = new byte[size];
246 while ((len = is.read(buf, 0, size)) != -1)
247 bos.write(buf, 0, len);
248 buf = bos.toByteArray();
249 }
250 return buf;
251 }
252 }
253 |
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