1 /*
2 * Copyright 2013 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://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, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 /*
17 Copyright (c) 2004-2011 QOS.ch
18 All rights reserved.
19
20 Permission is hereby granted, free of charge, to any person obtaining
21 a copy of this software and associated documentation files (the
22 "Software"), to deal in the Software without restriction, including
23 without limitation the rights to use, copy, modify, merge, publish,
24 distribute, sublicense, and/or sell copies of the Software, and to
25 permit persons to whom the Software is furnished to do so, subject to
26 the following conditions:
27
28 The above copyright notice and this permission notice shall be
29 included in all copies or substantial portions of the Software.
30
31 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
38
39 */
40 package io.netty5.util.internal.logging;
41
42 import java.text.MessageFormat;
43 import java.util.HashSet;
44 import java.util.Set;
45
46 // contributors: lizongbo: proposed special treatment of array parameter values
47 // Joern Huxhorn: pointed out double[] omission, suggested deep array copy
48
49 /**
50 * Formats messages according to very simple substitution rules. Substitutions
51 * can be made 1, 2 or more arguments.
52 * <p/>
53 * <p/>
54 * For example,
55 * <p/>
56 * <pre>
57 * MessageFormatter.format("Hi {}.", "there")
58 * </pre>
59 * <p/>
60 * will return the string "Hi there.".
61 * <p/>
62 * The {} pair is called the <em>formatting anchor</em>. It serves to designate
63 * the location where arguments need to be substituted within the message
64 * pattern.
65 * <p/>
66 * In case your message contains the '{' or the '}' character, you do not have
67 * to do anything special unless the '}' character immediately follows '{'. For
68 * example,
69 * <p/>
70 * <pre>
71 * MessageFormatter.format("Set {1,2,3} is not equal to {}.", "1,2");
72 * </pre>
73 * <p/>
74 * will return the string "Set {1,2,3} is not equal to 1,2.".
75 * <p/>
76 * <p/>
77 * If for whatever reason you need to place the string "{}" in the message
78 * without its <em>formatting anchor</em> meaning, then you need to escape the
79 * '{' character with '\', that is the backslash character. Only the '{'
80 * character should be escaped. There is no need to escape the '}' character.
81 * For example,
82 * <p/>
83 * <pre>
84 * MessageFormatter.format("Set \\{} is not equal to {}.", "1,2");
85 * </pre>
86 * <p/>
87 * will return the string "Set {} is not equal to 1,2.".
88 * <p/>
89 * <p/>
90 * The escaping behavior just described can be overridden by escaping the escape
91 * character '\'. Calling
92 * <p/>
93 * <pre>
94 * MessageFormatter.format("File name is C:\\\\{}.", "file.zip");
95 * </pre>
96 * <p/>
97 * will return the string "File name is C:\file.zip".
98 * <p/>
99 * <p/>
100 * The formatting conventions are different than those of {@link MessageFormat}
101 * which ships with the Java platform. This is justified by the fact that
102 * SLF4J's implementation is 10 times faster than that of {@link MessageFormat}.
103 * This local performance difference is both measurable and significant in the
104 * larger context of the complete logging processing chain.
105 * <p/>
106 * <p/>
107 * See also {@link #format(String, Object)},
108 * {@link #format(String, Object, Object)} and
109 * {@link #arrayFormat(String, Object[])} methods for more details.
110 */
111 public final class MessageFormatter {
112 private static final String DELIM_STR = "{}";
113 private static final char ESCAPE_CHAR = '\\';
114
115 /**
116 * Performs single argument substitution for the 'messagePattern' passed as
117 * parameter.
118 * <p/>
119 * For example,
120 * <p/>
121 * <pre>
122 * MessageFormatter.format("Hi {}.", "there");
123 * </pre>
124 * <p/>
125 * will return the string "Hi there.".
126 * <p/>
127 *
128 * @param messagePattern The message pattern which will be parsed and formatted
129 * @param arg The argument to be substituted in place of the formatting anchor
130 * @return The formatted message
131 */
132 static FormattingTuple format(String messagePattern, Object arg) {
133 return arrayFormat(messagePattern, new Object[]{arg});
134 }
135
136 /**
137 * Performs a two argument substitution for the 'messagePattern' passed as
138 * parameter.
139 * <p/>
140 * For example,
141 * <p/>
142 * <pre>
143 * MessageFormatter.format("Hi {}. My name is {}.", "Alice", "Bob");
144 * </pre>
145 * <p/>
146 * will return the string "Hi Alice. My name is Bob.".
147 *
148 * @param messagePattern The message pattern which will be parsed and formatted
149 * @param argA The argument to be substituted in place of the first formatting
150 * anchor
151 * @param argB The argument to be substituted in place of the second formatting
152 * anchor
153 * @return The formatted message
154 */
155 static FormattingTuple format(final String messagePattern,
156 Object argA, Object argB) {
157 return arrayFormat(messagePattern, new Object[]{argA, argB});
158 }
159
160 /**
161 * Same principle as the {@link #format(String, Object)} and
162 * {@link #format(String, Object, Object)} methods except that any number of
163 * arguments can be passed in an array.
164 *
165 * @param messagePattern The message pattern which will be parsed and formatted
166 * @param argArray An array of arguments to be substituted in place of formatting
167 * anchors
168 * @return The formatted message
169 */
170 static FormattingTuple arrayFormat(final String messagePattern,
171 final Object[] argArray) {
172 if (argArray == null || argArray.length == 0) {
173 return new FormattingTuple(messagePattern, null);
174 }
175
176 int lastArrIdx = argArray.length - 1;
177 Object lastEntry = argArray[lastArrIdx];
178 Throwable throwable = lastEntry instanceof Throwable? (Throwable) lastEntry : null;
179
180 if (messagePattern == null) {
181 return new FormattingTuple(null, throwable);
182 }
183
184 int j = messagePattern.indexOf(DELIM_STR);
185 if (j == -1) {
186 // this is a simple string
187 return new FormattingTuple(messagePattern, throwable);
188 }
189
190 StringBuilder sbuf = new StringBuilder(messagePattern.length() + 50);
191 int i = 0;
192 int L = 0;
193 do {
194 boolean notEscaped = j == 0 || messagePattern.charAt(j - 1) != ESCAPE_CHAR;
195 if (notEscaped) {
196 // normal case
197 sbuf.append(messagePattern, i, j);
198 } else {
199 sbuf.append(messagePattern, i, j - 1);
200 // check that escape char is not is escaped: "abc x:\\{}"
201 notEscaped = j >= 2 && messagePattern.charAt(j - 2) == ESCAPE_CHAR;
202 }
203
204 i = j + 2;
205 if (notEscaped) {
206 deeplyAppendParameter(sbuf, argArray[L], null);
207 L++;
208 if (L > lastArrIdx) {
209 break;
210 }
211 } else {
212 sbuf.append(DELIM_STR);
213 }
214 j = messagePattern.indexOf(DELIM_STR, i);
215 } while (j != -1);
216
217 // append the characters following the last {} pair.
218 sbuf.append(messagePattern, i, messagePattern.length());
219 return new FormattingTuple(sbuf.toString(), L <= lastArrIdx? throwable : null);
220 }
221
222 // special treatment of array values was suggested by 'lizongbo'
223 private static void deeplyAppendParameter(StringBuilder sbuf, Object o,
224 Set<Object[]> seenSet) {
225 if (o == null) {
226 sbuf.append("null");
227 return;
228 }
229 Class<?> objClass = o.getClass();
230 if (!objClass.isArray()) {
231 if (Number.class.isAssignableFrom(objClass)) {
232 // Prevent String instantiation for some number types
233 if (objClass == Long.class) {
234 sbuf.append(((Long) o).longValue());
235 } else if (objClass == Integer.class || objClass == Short.class || objClass == Byte.class) {
236 sbuf.append(((Number) o).intValue());
237 } else if (objClass == Double.class) {
238 sbuf.append(((Double) o).doubleValue());
239 } else if (objClass == Float.class) {
240 sbuf.append(((Float) o).floatValue());
241 } else {
242 safeObjectAppend(sbuf, o);
243 }
244 } else {
245 safeObjectAppend(sbuf, o);
246 }
247 } else {
248 // check for primitive array types because they
249 // unfortunately cannot be cast to Object[]
250 sbuf.append('[');
251 if (objClass == boolean[].class) {
252 booleanArrayAppend(sbuf, (boolean[]) o);
253 } else if (objClass == byte[].class) {
254 byteArrayAppend(sbuf, (byte[]) o);
255 } else if (objClass == char[].class) {
256 charArrayAppend(sbuf, (char[]) o);
257 } else if (objClass == short[].class) {
258 shortArrayAppend(sbuf, (short[]) o);
259 } else if (objClass == int[].class) {
260 intArrayAppend(sbuf, (int[]) o);
261 } else if (objClass == long[].class) {
262 longArrayAppend(sbuf, (long[]) o);
263 } else if (objClass == float[].class) {
264 floatArrayAppend(sbuf, (float[]) o);
265 } else if (objClass == double[].class) {
266 doubleArrayAppend(sbuf, (double[]) o);
267 } else {
268 objectArrayAppend(sbuf, (Object[]) o, seenSet);
269 }
270 sbuf.append(']');
271 }
272 }
273
274 private static void safeObjectAppend(StringBuilder sbuf, Object o) {
275 try {
276 String oAsString = o.toString();
277 sbuf.append(oAsString);
278 } catch (Throwable t) {
279 System.err
280 .println("SLF4J: Failed toString() invocation on an object of type ["
281 + o.getClass().getName() + ']');
282 t.printStackTrace();
283 sbuf.append("[FAILED toString()]");
284 }
285 }
286
287 private static void objectArrayAppend(StringBuilder sbuf, Object[] a, Set<Object[]> seenSet) {
288 if (a.length == 0) {
289 return;
290 }
291 if (seenSet == null) {
292 seenSet = new HashSet<>(a.length);
293 }
294 if (seenSet.add(a)) {
295 deeplyAppendParameter(sbuf, a[0], seenSet);
296 for (int i = 1; i < a.length; i++) {
297 sbuf.append(", ");
298 deeplyAppendParameter(sbuf, a[i], seenSet);
299 }
300 // allow repeats in siblings
301 seenSet.remove(a);
302 } else {
303 sbuf.append("...");
304 }
305 }
306
307 private static void booleanArrayAppend(StringBuilder sbuf, boolean[] a) {
308 if (a.length == 0) {
309 return;
310 }
311 sbuf.append(a[0]);
312 for (int i = 1; i < a.length; i++) {
313 sbuf.append(", ");
314 sbuf.append(a[i]);
315 }
316 }
317
318 private static void byteArrayAppend(StringBuilder sbuf, byte[] a) {
319 if (a.length == 0) {
320 return;
321 }
322 sbuf.append(a[0]);
323 for (int i = 1; i < a.length; i++) {
324 sbuf.append(", ");
325 sbuf.append(a[i]);
326 }
327 }
328
329 private static void charArrayAppend(StringBuilder sbuf, char[] a) {
330 if (a.length == 0) {
331 return;
332 }
333 sbuf.append(a[0]);
334 for (int i = 1; i < a.length; i++) {
335 sbuf.append(", ");
336 sbuf.append(a[i]);
337 }
338 }
339
340 private static void shortArrayAppend(StringBuilder sbuf, short[] a) {
341 if (a.length == 0) {
342 return;
343 }
344 sbuf.append(a[0]);
345 for (int i = 1; i < a.length; i++) {
346 sbuf.append(", ");
347 sbuf.append(a[i]);
348 }
349 }
350
351 private static void intArrayAppend(StringBuilder sbuf, int[] a) {
352 if (a.length == 0) {
353 return;
354 }
355 sbuf.append(a[0]);
356 for (int i = 1; i < a.length; i++) {
357 sbuf.append(", ");
358 sbuf.append(a[i]);
359 }
360 }
361
362 private static void longArrayAppend(StringBuilder sbuf, long[] a) {
363 if (a.length == 0) {
364 return;
365 }
366 sbuf.append(a[0]);
367 for (int i = 1; i < a.length; i++) {
368 sbuf.append(", ");
369 sbuf.append(a[i]);
370 }
371 }
372
373 private static void floatArrayAppend(StringBuilder sbuf, float[] a) {
374 if (a.length == 0) {
375 return;
376 }
377 sbuf.append(a[0]);
378 for (int i = 1; i < a.length; i++) {
379 sbuf.append(", ");
380 sbuf.append(a[i]);
381 }
382 }
383
384 private static void doubleArrayAppend(StringBuilder sbuf, double[] a) {
385 if (a.length == 0) {
386 return;
387 }
388 sbuf.append(a[0]);
389 for (int i = 1; i < a.length; i++) {
390 sbuf.append(", ");
391 sbuf.append(a[i]);
392 }
393 }
394
395 private MessageFormatter() {
396 }
397 }