source: josm/trunk/src/org/openstreetmap/josm/tools/I18n.java@ 13520

Last change on this file since 13520 was 13509, checked in by Don-vip, 6 years ago

fix #16060 - NPE + minor fixes
  • Property svn:eol-style set to native
File size: 25.0 KB
Line 
1// License: GPL. For details, see LICENSE file.
2package org.openstreetmap.josm.tools;
3
4import java.io.BufferedInputStream;
5import java.io.File;
6import java.io.IOException;
7import java.io.InputStream;
8import java.lang.annotation.Retention;
9import java.lang.annotation.RetentionPolicy;
10import java.net.URL;
11import java.nio.charset.StandardCharsets;
12import java.nio.file.InvalidPathException;
13import java.text.MessageFormat;
14import java.util.ArrayList;
15import java.util.Arrays;
16import java.util.Collection;
17import java.util.Comparator;
18import java.util.HashMap;
19import java.util.Locale;
20import java.util.Map;
21import java.util.zip.ZipEntry;
22import java.util.zip.ZipFile;
23
24/**
25 * Internationalisation support.
26 *
27 * @author Immanuel.Scholz
28 */
29public final class I18n {
30
31 /**
32 * This annotates strings which do not permit a clean i18n. This is mostly due to strings
33 * containing two nouns which can occur in singular or plural form.
34 * <br>
35 * No behaviour is associated with this annotation.
36 */
37 @Retention(RetentionPolicy.SOURCE)
38 public @interface QuirkyPluralString {
39 }
40
41 private I18n() {
42 // Hide default constructor for utils classes
43 }
44
45 /**
46 * Enumeration of possible plural modes. It allows us to identify and implement logical conditions of
47 * plural forms defined on <a href="https://help.launchpad.net/Translations/PluralForms">Launchpad</a>.
48 * See <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html">CLDR</a>
49 * for another complete list.
50 * @see #pluralEval
51 */
52 private enum PluralMode {
53 /** Plural = Not 1. This is the default for many languages, including English: 1 day, but 0 days or 2 days. */
54 MODE_NOTONE,
55 /** No plural. Mainly for Asian languages (Indonesian, Chinese, Japanese, ...) */
56 MODE_NONE,
57 /** Plural = Greater than 1. For some latin languages (French, Brazilian Portuguese) */
58 MODE_GREATERONE,
59 /* Special mode for
60 * <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#ar">Arabic</a>.*
61 MODE_AR,*/
62 /** Special mode for
63 * <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#cs">Czech</a>. */
64 MODE_CS,
65 /** Special mode for
66 * <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#pl">Polish</a>. */
67 MODE_PL,
68 /* Special mode for
69 * <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#ro">Romanian</a>.*
70 MODE_RO,*/
71 /** Special mode for
72 * <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#lt">Lithuanian</a>. */
73 MODE_LT,
74 /** Special mode for
75 * <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#ru">Russian</a>. */
76 MODE_RU,
77 /** Special mode for
78 * <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#sk">Slovak</a>. */
79 MODE_SK,
80 /* Special mode for
81 * <a href="http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html#sl">Slovenian</a>.*
82 MODE_SL,*/
83 }
84
85 private static volatile PluralMode pluralMode = PluralMode.MODE_NOTONE; /* english default */
86 private static volatile String loadedCode = "en";
87
88
89 private static volatile Map<String, String> strings;
90 private static volatile Map<String, String[]> pstrings;
91 private static Map<String, PluralMode> languages = new HashMap<>();
92 static {
93 //languages.put("ar", PluralMode.MODE_AR);
94 languages.put("ast", PluralMode.MODE_NOTONE);
95 languages.put("bg", PluralMode.MODE_NOTONE);
96 languages.put("be", PluralMode.MODE_RU);
97 languages.put("ca", PluralMode.MODE_NOTONE);
98 languages.put("ca@valencia", PluralMode.MODE_NOTONE);
99 languages.put("cs", PluralMode.MODE_CS);
100 languages.put("da", PluralMode.MODE_NOTONE);
101 languages.put("de", PluralMode.MODE_NOTONE);
102 languages.put("el", PluralMode.MODE_NOTONE);
103 languages.put("en_AU", PluralMode.MODE_NOTONE);
104 languages.put("en_GB", PluralMode.MODE_NOTONE);
105 languages.put("es", PluralMode.MODE_NOTONE);
106 languages.put("et", PluralMode.MODE_NOTONE);
107 //languages.put("eu", PluralMode.MODE_NOTONE);
108 languages.put("fi", PluralMode.MODE_NOTONE);
109 languages.put("fr", PluralMode.MODE_GREATERONE);
110 languages.put("gl", PluralMode.MODE_NOTONE);
111 //languages.put("he", PluralMode.MODE_NOTONE);
112 languages.put("hu", PluralMode.MODE_NOTONE);
113 languages.put("id", PluralMode.MODE_NONE);
114 //languages.put("is", PluralMode.MODE_NOTONE);
115 languages.put("it", PluralMode.MODE_NOTONE);
116 languages.put("ja", PluralMode.MODE_NONE);
117 // fully supported only with Java 8 and later (needs CLDR)
118 languages.put("km", PluralMode.MODE_NONE);
119 languages.put("lt", PluralMode.MODE_LT);
120 languages.put("nb", PluralMode.MODE_NOTONE);
121 languages.put("nl", PluralMode.MODE_NOTONE);
122 languages.put("pl", PluralMode.MODE_PL);
123 languages.put("pt", PluralMode.MODE_NOTONE);
124 languages.put("pt_BR", PluralMode.MODE_GREATERONE);
125 //languages.put("ro", PluralMode.MODE_RO);
126 languages.put("ru", PluralMode.MODE_RU);
127 languages.put("sk", PluralMode.MODE_SK);
128 //languages.put("sl", PluralMode.MODE_SL);
129 languages.put("sv", PluralMode.MODE_NOTONE);
130 //languages.put("tr", PluralMode.MODE_NONE);
131 languages.put("uk", PluralMode.MODE_RU);
132 languages.put("vi", PluralMode.MODE_NONE);
133 languages.put("zh_CN", PluralMode.MODE_NONE);
134 languages.put("zh_TW", PluralMode.MODE_NONE);
135 }
136
137 /**
138 * Translates some text for the current locale.
139 * These strings are collected by a script that runs on the source code files.
140 * After translation, the localizations are distributed with the main program.
141 * <br>
142 * For example, <code>tr("JOSM''s default value is ''{0}''.", val)</code>.
143 * <br>
144 * Use {@link #trn} for distinguishing singular from plural text, i.e.,
145 * do not use {@code tr(size == 1 ? "singular" : "plural")} nor
146 * {@code size == 1 ? tr("singular") : tr("plural")}
147 *
148 * @param text the text to translate.
149 * Must be a string literal. (No constants or local vars.)
150 * Can be broken over multiple lines.
151 * An apostrophe ' must be quoted by another apostrophe.
152 * @param objects the parameters for the string.
153 * Mark occurrences in {@code text} with <code>{0}</code>, <code>{1}</code>, ...
154 * @return the translated string.
155 * @see #trn
156 * @see #trc
157 * @see #trnc
158 */
159 public static String tr(String text, Object... objects) {
160 if (text == null) return null;
161 return MessageFormat.format(gettext(text, null), objects);
162 }
163
164 /**
165 * Translates some text in a context for the current locale.
166 * There can be different translations for the same text within different contexts.
167 *
168 * @param context string that helps translators to find an appropriate
169 * translation for {@code text}.
170 * @param text the text to translate.
171 * @return the translated string.
172 * @see #tr
173 * @see #trn
174 * @see #trnc
175 */
176 public static String trc(String context, String text) {
177 if (context == null)
178 return tr(text);
179 if (text == null)
180 return null;
181 return MessageFormat.format(gettext(text, context), (Object) null);
182 }
183
184 public static String trcLazy(String context, String text) {
185 if (context == null)
186 return tr(text);
187 if (text == null)
188 return null;
189 return MessageFormat.format(gettextLazy(text, context), (Object) null);
190 }
191
192 /**
193 * Marks a string for translation (such that a script can harvest
194 * the translatable strings from the source files).
195 *
196 * For example, <code>
197 * String[] options = new String[] {marktr("up"), marktr("down")};
198 * lbl.setText(tr(options[0]));</code>
199 * @param text the string to be marked for translation.
200 * @return {@code text} unmodified.
201 */
202 public static String marktr(String text) {
203 return text;
204 }
205
206 public static String marktrc(String context, String text) {
207 return text;
208 }
209
210 /**
211 * Translates some text for the current locale and distinguishes between
212 * {@code singularText} and {@code pluralText} depending on {@code n}.
213 * <br>
214 * For instance, {@code trn("There was an error!", "There were errors!", i)} or
215 * <code>trn("Found {0} error in {1}!", "Found {0} errors in {1}!", i, Integer.toString(i), url)</code>.
216 *
217 * @param singularText the singular text to translate.
218 * Must be a string literal. (No constants or local vars.)
219 * Can be broken over multiple lines.
220 * An apostrophe ' must be quoted by another apostrophe.
221 * @param pluralText the plural text to translate.
222 * Must be a string literal. (No constants or local vars.)
223 * Can be broken over multiple lines.
224 * An apostrophe ' must be quoted by another apostrophe.
225 * @param n a number to determine whether {@code singularText} or {@code pluralText} is used.
226 * @param objects the parameters for the string.
227 * Mark occurrences in {@code singularText} and {@code pluralText} with <code>{0}</code>, <code>{1}</code>, ...
228 * @return the translated string.
229 * @see #tr
230 * @see #trc
231 * @see #trnc
232 */
233 public static String trn(String singularText, String pluralText, long n, Object... objects) {
234 return MessageFormat.format(gettextn(singularText, pluralText, null, n), objects);
235 }
236
237 /**
238 * Translates some text in a context for the current locale and distinguishes between
239 * {@code singularText} and {@code pluralText} depending on {@code n}.
240 * There can be different translations for the same text within different contexts.
241 *
242 * @param context string that helps translators to find an appropriate
243 * translation for {@code text}.
244 * @param singularText the singular text to translate.
245 * Must be a string literal. (No constants or local vars.)
246 * Can be broken over multiple lines.
247 * An apostrophe ' must be quoted by another apostrophe.
248 * @param pluralText the plural text to translate.
249 * Must be a string literal. (No constants or local vars.)
250 * Can be broken over multiple lines.
251 * An apostrophe ' must be quoted by another apostrophe.
252 * @param n a number to determine whether {@code singularText} or {@code pluralText} is used.
253 * @param objects the parameters for the string.
254 * Mark occurrences in {@code singularText} and {@code pluralText} with <code>{0}</code>, <code>{1}</code>, ...
255 * @return the translated string.
256 * @see #tr
257 * @see #trc
258 * @see #trn
259 */
260 public static String trnc(String context, String singularText, String pluralText, long n, Object... objects) {
261 return MessageFormat.format(gettextn(singularText, pluralText, context, n), objects);
262 }
263
264 private static String gettext(String text, String ctx, boolean lazy) {
265 int i;
266 if (ctx == null && text.startsWith("_:") && (i = text.indexOf('\n')) >= 0) {
267 ctx = text.substring(2, i-1);
268 text = text.substring(i+1);
269 }
270 if (strings != null) {
271 String trans = strings.get(ctx == null ? text : "_:"+ctx+'\n'+text);
272 if (trans != null)
273 return trans;
274 }
275 if (pstrings != null) {
276 i = pluralEval(1);
277 String[] trans = pstrings.get(ctx == null ? text : "_:"+ctx+'\n'+text);
278 if (trans != null && trans.length > i)
279 return trans[i];
280 }
281 return lazy ? gettext(text, null) : text;
282 }
283
284 private static String gettext(String text, String ctx) {
285 return gettext(text, ctx, false);
286 }
287
288 /* try without context, when context try fails */
289 private static String gettextLazy(String text, String ctx) {
290 return gettext(text, ctx, true);
291 }
292
293 private static String gettextn(String text, String plural, String ctx, long num) {
294 int i;
295 if (ctx == null && text.startsWith("_:") && (i = text.indexOf('\n')) >= 0) {
296 ctx = text.substring(2, i-1);
297 text = text.substring(i+1);
298 }
299 if (pstrings != null) {
300 i = pluralEval(num);
301 String[] trans = pstrings.get(ctx == null ? text : "_:"+ctx+'\n'+text);
302 if (trans != null && trans.length > i)
303 return trans[i];
304 }
305
306 return num == 1 ? text : plural;
307 }
308
309 public static String escape(String msg) {
310 if (msg == null) return null;
311 return msg.replace("\'", "\'\'").replace("{", "\'{\'").replace("}", "\'}\'");
312 }
313
314 private static URL getTranslationFile(String lang) {
315 return I18n.class.getResource("/data/"+lang.replace('@', '-')+".lang");
316 }
317
318 /**
319 * Get a list of all available JOSM Translations.
320 * @return an array of locale objects.
321 */
322 public static Locale[] getAvailableTranslations() {
323 Collection<Locale> v = new ArrayList<>(languages.size());
324 if (getTranslationFile("en") != null) {
325 for (String loc : languages.keySet()) {
326 if (getTranslationFile(loc) != null) {
327 v.add(LanguageInfo.getLocale(loc));
328 }
329 }
330 }
331 v.add(Locale.ENGLISH);
332 Locale[] l = new Locale[v.size()];
333 l = v.toArray(l);
334 Arrays.sort(l, Comparator.comparing(Locale::toString));
335 return l;
336 }
337
338 /**
339 * Determines if a language exists for the given code.
340 * @param code The language code
341 * @return {@code true} if a language exists, {@code false} otherwise
342 */
343 public static boolean hasCode(String code) {
344 return languages.containsKey(code);
345 }
346
347 static void setupJavaLocaleProviders() {
348 // Look up SPI providers first (for JosmDecimalFormatSymbolsProvider).
349 // Enable CLDR locale provider on Java 8 to get additional languages, such as Khmer.
350 // http://docs.oracle.com/javase/8/docs/technotes/guides/intl/enhancements.8.html#cldr
351 // FIXME: This must be updated after we switch to Java 9.
352 // See https://docs.oracle.com/javase/9/docs/api/java/util/spi/LocaleServiceProvider.html
353 System.setProperty("java.locale.providers", "SPI,JRE,CLDR"); // Don't call Utils.updateSystemProperty to avoid spurious log at startup
354 }
355
356 /**
357 * I18n initialization.
358 */
359 public static void init() {
360 setupJavaLocaleProviders();
361
362 /* try initial language settings, may be changed later again */
363 if (!load(LanguageInfo.getJOSMLocaleCode())) {
364 Locale.setDefault(Locale.ENGLISH);
365 }
366 }
367
368 /**
369 * I18n initialization for plugins.
370 * @param source file path/name of the JAR or Zip file containing translation strings
371 * @since 4159
372 */
373 public static void addTexts(File source) {
374 if ("en".equals(loadedCode))
375 return;
376 final ZipEntry enfile = new ZipEntry("data/en.lang");
377 final ZipEntry langfile = new ZipEntry("data/"+loadedCode+".lang");
378 try (
379 ZipFile zipFile = new ZipFile(source, StandardCharsets.UTF_8);
380 InputStream orig = zipFile.getInputStream(enfile);
381 InputStream trans = zipFile.getInputStream(langfile);
382 ) {
383 if (orig != null && trans != null)
384 load(orig, trans, true);
385 } catch (IOException | InvalidPathException e) {
386 Logging.trace(e);
387 }
388 }
389
390 private static boolean load(String l) {
391 if ("en".equals(l) || "en_US".equals(l)) {
392 strings = null;
393 pstrings = null;
394 loadedCode = "en";
395 pluralMode = PluralMode.MODE_NOTONE;
396 return true;
397 }
398 URL en = getTranslationFile("en");
399 if (en == null)
400 return false;
401 URL tr = getTranslationFile(l);
402 if (tr == null || !languages.containsKey(l)) {
403 return false;
404 }
405 try (
406 InputStream enStream = Utils.openStream(en);
407 InputStream trStream = Utils.openStream(tr)
408 ) {
409 if (load(enStream, trStream, false)) {
410 pluralMode = languages.get(l);
411 loadedCode = l;
412 return true;
413 }
414 } catch (IOException e) {
415 // Ignore exception
416 Logging.trace(e);
417 }
418 return false;
419 }
420
421 private static boolean load(InputStream en, InputStream tr, boolean add) {
422 Map<String, String> s;
423 Map<String, String[]> p;
424 if (add) {
425 s = strings;
426 p = pstrings;
427 } else {
428 s = new HashMap<>();
429 p = new HashMap<>();
430 }
431 /* file format:
432 Files are always a group. English file and translated file must provide identical datasets.
433
434 for all single strings:
435 {
436 unsigned short (2 byte) stringlength
437 - length 0 indicates missing translation
438 - length 0xFFFE indicates translation equal to original, but otherwise is equal to length 0
439 string
440 }
441 unsigned short (2 byte) 0xFFFF (marks end of single strings)
442 for all multi strings:
443 {
444 unsigned char (1 byte) stringcount
445 - count 0 indicates missing translations
446 - count 0xFE indicates translations equal to original, but otherwise is equal to length 0
447 for stringcount
448 unsigned short (2 byte) stringlength
449 string
450 }
451 */
452 try {
453 InputStream ens = new BufferedInputStream(en);
454 InputStream trs = new BufferedInputStream(tr);
455 byte[] enlen = new byte[2];
456 byte[] trlen = new byte[2];
457 boolean multimode = false;
458 byte[] str = new byte[4096];
459 for (;;) {
460 if (multimode) {
461 int ennum = ens.read();
462 int trnum = trs.read();
463 if (trnum == 0xFE) /* marks identical string, handle equally to non-translated */
464 trnum = 0;
465 if ((ennum == -1 && trnum != -1) || (ennum != -1 && trnum == -1)) /* files do not match */
466 return false;
467 if (ennum == -1) {
468 break;
469 }
470 String[] enstrings = new String[ennum];
471 for (int i = 0; i < ennum; ++i) {
472 int val = ens.read(enlen);
473 if (val != 2) /* file corrupt */
474 return false;
475 val = (enlen[0] < 0 ? 256+enlen[0] : enlen[0])*256+(enlen[1] < 0 ? 256+enlen[1] : enlen[1]);
476 if (val > str.length) {
477 str = new byte[val];
478 }
479 int rval = ens.read(str, 0, val);
480 if (rval != val) /* file corrupt */
481 return false;
482 enstrings[i] = new String(str, 0, val, StandardCharsets.UTF_8);
483 }
484 String[] trstrings = new String[trnum];
485 for (int i = 0; i < trnum; ++i) {
486 int val = trs.read(trlen);
487 if (val != 2) /* file corrupt */
488 return false;
489 val = (trlen[0] < 0 ? 256+trlen[0] : trlen[0])*256+(trlen[1] < 0 ? 256+trlen[1] : trlen[1]);
490 if (val > str.length) {
491 str = new byte[val];
492 }
493 int rval = trs.read(str, 0, val);
494 if (rval != val) /* file corrupt */
495 return false;
496 trstrings[i] = new String(str, 0, val, StandardCharsets.UTF_8);
497 }
498 if (trnum > 0 && !p.containsKey(enstrings[0])) {
499 p.put(enstrings[0], trstrings);
500 }
501 } else {
502 int enval = ens.read(enlen);
503 int trval = trs.read(trlen);
504 if (enval != trval) /* files do not match */
505 return false;
506 if (enval == -1) {
507 break;
508 }
509 if (enval != 2) /* files corrupt */
510 return false;
511 enval = (enlen[0] < 0 ? 256+enlen[0] : enlen[0])*256+(enlen[1] < 0 ? 256+enlen[1] : enlen[1]);
512 trval = (trlen[0] < 0 ? 256+trlen[0] : trlen[0])*256+(trlen[1] < 0 ? 256+trlen[1] : trlen[1]);
513 if (trval == 0xFFFE) /* marks identical string, handle equally to non-translated */
514 trval = 0;
515 if (enval == 0xFFFF) {
516 multimode = true;
517 if (trval != 0xFFFF) /* files do not match */
518 return false;
519 } else {
520 if (enval > str.length) {
521 str = new byte[enval];
522 }
523 if (trval > str.length) {
524 str = new byte[trval];
525 }
526 int val = ens.read(str, 0, enval);
527 if (val != enval) /* file corrupt */
528 return false;
529 String enstr = new String(str, 0, enval, StandardCharsets.UTF_8);
530 if (trval != 0) {
531 val = trs.read(str, 0, trval);
532 if (val != trval) /* file corrupt */
533 return false;
534 String trstr = new String(str, 0, trval, StandardCharsets.UTF_8);
535 if (!s.containsKey(enstr))
536 s.put(enstr, trstr);
537 }
538 }
539 }
540 }
541 } catch (IOException e) {
542 Logging.trace(e);
543 return false;
544 }
545 if (!s.isEmpty()) {
546 strings = s;
547 pstrings = p;
548 return true;
549 }
550 return false;
551 }
552
553 /**
554 * Sets the default locale (see {@link Locale#setDefault(Locale)} to the local
555 * given by <code>localName</code>.
556 *
557 * Ignored if localeName is null. If the locale with name <code>localName</code>
558 * isn't found the default local is set to <code>en</code> (english).
559 *
560 * @param localeName the locale name. Ignored if null.
561 */
562 public static void set(String localeName) {
563 if (localeName != null) {
564 Locale l = LanguageInfo.getLocale(localeName);
565 if (load(LanguageInfo.getJOSMLocaleCode(l))) {
566 Locale.setDefault(l);
567 } else {
568 if (!"en".equals(l.getLanguage())) {
569 Logging.info(tr("Unable to find translation for the locale {0}. Reverting to {1}.",
570 LanguageInfo.getDisplayName(l), LanguageInfo.getDisplayName(Locale.getDefault())));
571 } else {
572 strings = null;
573 pstrings = null;
574 }
575 }
576 }
577 }
578
579 private static int pluralEval(long n) {
580 switch(pluralMode) {
581 case MODE_NOTONE: /* bg, da, de, el, en, en_GB, es, et, eu, fi, gl, is, it, iw_IL, nb, nl, sv */
582 return (n != 1) ? 1 : 0;
583 case MODE_NONE: /* id, vi, ja, km, tr, zh_CN, zh_TW */
584 return 0;
585 case MODE_GREATERONE: /* fr, pt_BR */
586 return (n > 1) ? 1 : 0;
587 case MODE_CS:
588 return (n == 1) ? 0 : (((n >= 2) && (n <= 4)) ? 1 : 2);
589 //case MODE_AR:
590 // return ((n == 0) ? 0 : ((n == 1) ? 1 : ((n == 2) ? 2 : ((((n % 100) >= 3)
591 // && ((n % 100) <= 10)) ? 3 : ((((n % 100) >= 11) && ((n % 100) <= 99)) ? 4 : 5)))));
592 case MODE_PL:
593 return (n == 1) ? 0 : (((((n % 10) >= 2) && ((n % 10) <= 4))
594 && (((n % 100) < 10) || ((n % 100) >= 20))) ? 1 : 2);
595 //case MODE_RO:
596 // return ((n == 1) ? 0 : ((((n % 100) > 19) || (((n % 100) == 0) && (n != 0))) ? 2 : 1));
597 case MODE_LT:
598 return ((n % 10) == 1) && ((n % 100) != 11) ? 0 : (((n % 10) >= 2)
599 && (((n % 100) < 10) || ((n % 100) >= 20)) ? 1 : 2);
600 case MODE_RU:
601 return (((n % 10) == 1) && ((n % 100) != 11)) ? 0 : (((((n % 10) >= 2)
602 && ((n % 10) <= 4)) && (((n % 100) < 10) || ((n % 100) >= 20))) ? 1 : 2);
603 case MODE_SK:
604 return (n == 1) ? 1 : (((n >= 2) && (n <= 4)) ? 2 : 0);
605 //case MODE_SL:
606 // return (((n % 100) == 1) ? 1 : (((n % 100) == 2) ? 2 : ((((n % 100) == 3)
607 // || ((n % 100) == 4)) ? 3 : 0)));
608 }
609 return 0;
610 }
611}
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